The Art of Woodworking - Wood Finishing

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Transcript of The Art of Woodworking - Wood Finishing

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IItIItI

THE ART OF WOODWORKING

HOMEWORI$HOP

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WORKSHOP GUIDECHOO'ING A BRUSHWhile a eeaeoned finiaher can applya atain or topcoat ekillfully with vir'tually any bruah, moat people arebetter off buyinq a qood-quality tool.The bruah ahown cut away at riqhtmay coot more than a lower qualitymodel, but it includea cerLain fea-turea that will enaure conaiatently4ood reaulto.

There are two kinda of bruahea onthe market: natural- and aynthetic'brietle ty pee. N atural - briatlebruehee are made from boar, aable,camel, ox or badqer hair, tsoar-briatle ("China hog") bruahee areideal for applyinq varnieh. )thernatural-briatle bruahea are beatauited to lacauer and ahellac,They are a po6r choice, however, forop re adi n4 water- ba eed fi n i sh e ebecauae they may cauae the finiahto foam up.

gynth dtic-fil a m ent b ru ah ea a remade of nylon or polyeeter, or both.Theae bruahee are your beat bet fora p plyi n g wate r- ba aed p ro d u cta.Durable and flexible, they can alaobe uaed with varniah andpenetratin4 oil etain s.

DividerTapered plu7 thateeparatee bdatlea_into qroupo, forminqa reaervoir

Epoxy plug -Bonda ferrule-end of brietleetogether with epoxy qlue

BristlesNatural bristlea or ayntheticfilamente; tipe can be cut flator tapered to a chiael tip

ANATOMY OF A PAINTBRUSH

HandleCan be made of plaaticor hardwood; balancedand deoi4ned for comforb

Retaining pinNail or rivet.that bindeferrule to handle

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FerruleA riqid, corroeion-reaiatant metal bandthat holda brietleaand epoxy plug

ReaervoirA apace that holdafiniah aa it ia beinqopread on by briatleo

CHISEL-TIP BRISTTESNATURAL AND SYNTHETIC BRISTTE TIPS

Tipped)traiqht-cuttipo recom-mended forwater-bagedfiniahea

TaperedTipe honed to afine point; ideal foroil-baaed productoItke varnish

Flagged1plit enda holdmore finiah andepread it moreomoothly thantipped or ta-pered Lipe

. Pay a l itt le more to get a superior-qual i ty brush; a bet ter brush wi l limprove your results.

. Avoid brushes with hollow bristles.Unl ike sol id br is t les, hol low ones donot spr ing back to thei r or ig inal shapewhen bent.

. For a good-quality, all-purpose brush,choose a chisel t ip model with longspringy bristles-soft for thin water-based finishes and stiff for heaw-

TIPS ON BRUSH SELECTION

bodied products such as shellac, lacquerand varn ish.

o lf you want a brush with f lagged bris-tle tips, check for branch-like split ends,

. l f you are looking for a tapered-br is t le brush, make sure that thebr is t res are th icker at the ferru leend than at the t io .

. Buy brushes that have good spr ing.Squeeze the br is t les wi th your hand

and bend them; they should feelfu l l and spr ing back to thei r or ig-inal posi t ions.

. Confirm that the bristles are dif-ferent lengths by running your handdown one side of the bristles from theferrule to the tip; the shorter bristless h n r r l d s n r i n o r r n

r Make sure that the bristles are f irmlyset in the ferrule, which should besecurely fastened to the handle.

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THE ART OF WOODWORKING

WOODFINISHING

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WOOD

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THE ART OF WOODWORKING

FINISHING

TIME-LIFE BOOKSALEXANDRIA, VIRGINIA

ST. REMY PRESSMONTREAL. NEW YORK

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THE ART OF WOODWORKING was produced byST. REMYPRESS

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Pierre Home-DouglasFrancine LemieuxMarc Cassini (Text)Heather Mills (Research)Normand Boudreault, Solange LabergeLuc GermainIim McRaeChristopher JackonTamsin M. Douglas, Andrew lonesLaura TringaliMichel Blais, Jean-Pierre Bourgeois,Ronald Durepos, Serge Guibord,Robert Paquet, facques Perrault,James Th6rien, focelyn VeilletteNatalie WatanabeMichelle Turbidefean-Luc RoyRobert ChartierChristine M. IacobsIudith Yelon

THECONSUTTANTS

Michael Dresdner is a former contributingeditor to Fine Woodworking magazine. He cur-rently writes the "Just Finishing" column forAm erican Woodworker magazine.

Frank Klausz owns and operates Frank's CabinetShop in Pluckemin, New Jersey. He contributesto Fine Woodworkingmagazine and has madevideotapes with Taunton Press, including oneon wood finishing.

Paul McGoldrick owns and operates PianoforteInc., a piano restoration company in Montreal,Quebec. He is responsible for the maintenanceand concert preparation of the pianos used by theMontreal Symphony Orchestra and the NationalArts Center Orchestra in Ottawa, Ontario.

Giles Miller-Mead has taught advanced cabinet-rnaking at Montreal technical schools for morethan 10 years. A native ofNew Zealand, he previ-ously worked as a restorer of antique furniture.

Joseph Truini is Senior Editor of HozeMechanixmagazine. A former Shop and ToolsEditor of Popular Mechanics, he has worked asa cabinetmaker, home improvement contractorand carpenter.

Wood Finishingp. cm.-(The Art of Woodworking)

Includes index.ISBN 0-8094-9912-6 (trade)rsBN 0-8094-e9 r3-4 (lib)l. Wood Finishing.I. Time- Life Books. II. SeriesTT325.W66 1992684.1'043-dc20 92-32892

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For information about any Time-Life book,please call I-800-621-7026, or write:Reader InformationTime-Life Customer ServiceP.O. Box C-32068Richmond, Virginia2326t-2068

@ 1992 Time-Life Books Inc.All rights reserved.No part of this book may be reproduced inany form or by any electronic or mechanicalmeans, including information storage andretrieval devices or systems, without priorwritten permission from the publisher, exceptthat briefpassages may be quoted for reviews.First printing. Printed in U.S.A.Published simultaneously in Canada.

TIME-LIFE is a trademark of Time WarnerInc. U.S.A.

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Time-Life Books is a division of Time-Life Inc.,a wholly owned subsidiary of

THE TIME INC. BOOK COMPANY

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Managing EditorDirector of Editorial Resources

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MaryN. DavisRobert H. SmithThomas H. FlahertyElise D. Ritter-Clough

Trevor LunnRegina HallDonia Ann SteeleBob DoyleMarlene Zack

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CONTENTS

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202224303543505 1

6 INTRODUCTION

12 SAFETY

IIO DECORAIIVEFINISHESII2 Tools and accessories113 Stenciling118 Graining122 Marbling

126 FINISHING TOUCHESI28 Tools and accessoriesI29 Preparing to rub out the finish130 Rubbing out a finish

136 CLEANING AND STORAGE

140 GrossARY

I42 INDEX

I44 ACKNOWLEDGMENTS

PREPARING THE SURFACETools and accessoriesPlaningScrapingSandingRepairing surface damageRaising the grainFilling the grain

54 CHANGING THE COLOR56 Tools and accessories57 Bleaching59 The varieties of wood stains60 Dve stains64 Pigment stains68 Staining wood75 Pickling a wood surface76 Chemical stains80 Fuming

82 PROTECTIVE FINISHES84 Tools and accessories86 Choosing a protective finish91 Finishing by hand93 Setting up your spray equipment97 Working with spray equipment

I02 Anatomy of a spray roomI04 Identifting and avoiding

spray problems106 French polishing

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INTRODUCTION

Paul McGoldrick describes

FINISHINGAPIANO

y career in restoring pianos began like a lot of opportunities in life-by chance.When I was 231 had a cabinetmaking shop in Montrdal; next door was a

Parisian cabinetmaker, Jean Gilles Jozon. Jean was a cabinetmaker of the old traditionand I spent many hours in his atelier leaming about different finishing methods-tech-niques that haven't changed for generations. I later followed him to Paris and spenta working holiday there restoring antiques.

Through mutual friends I met a piano technician named Gilles Losier, and I begandoing finishing work on pianos he was restoring. In his youth, Gilles had a foremanwho could select the wood for a piano case, install the soundboard, string the piano,cut the keys, and assemble and regulate the mechanism. He could even sit down andplay a tune. Sadly, craftsmen with that range of expertise in the piano trade have allbut vanished.

Restoring pianos presents many challenges: The instrument must not only lookgreat; it must also sound superb and respond well mechanically. The instrument shownin the photograph is a 7-foot Chickering and Sons grand piano built in Boston in 1875.I counted 10 different woods used in its making, although the entire surface is veneeredwith Brazilian rosewood.

My first task involved filling the grain of the wood with a dark paste filler. I thenapplied a coat ofsanding sealer, and next sprayed on eight coats oflacquer. To keepthe final finish thin and to level any depressions caused by the large pores ofthe rose-wood veneer, I cut every second lacquer coating with 220-grit sandpaper.

The Iegs demanded special attention. Theywere made from large blocks of poplarwood so I had to create my own stain, blending in just enough yellow and red to sim-ulate rosewood's distinctive hue. I sketched in gain lines using a combination of feath-ers and brushes, with the top of the piano standing nearby as a guide. The grainpatterns in rosewood can get quite wild, so you can take artistic liberties in trying tosimulate it as long as you respect a few rules, such as keeping the grain lines runningparallel.

The final coat of finish was sanded with 220-grit and then 400-grit paper. All thatremained at the time this photo was taken was to rub the finish to a soft gloss with0000 steel wool, buffwith a cotton cloth and apply acarnauba-based wax.

Paul McGoldrick finishes and restorespianos in his shop in Montrdal, Qudbec.

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INTRODUCTION

Thomas Moser talks about

LINSEED OIL

y introduction to the craft of building furniture was with l9th-CenturyAmerican antiques and remnants of antiques. I u'ould buy a chest of drawers

without drawers, for example, and that would lead me to figuring out how drawerswere made. Because of my fascination with older pieces, I was attracted to buttermilkpaint, early varnishes and French polish.

Gradually my interest was drawn to the austerely elegant furniture made by theShakers and one of their favorite finishes-boiled linseed oil. I experimented andcame up with my own way of applying the oil and then paste wax to create a clearfinish like the one used on the piece in the photograph. Made of cherry, it is whatI call the "Bob Cratchet desk." It's a desk for an accountant or schoolteacher, althoughit can just as well be used as a lectern or telephone table. It has a drawer and a remov-able oencil rack.

Linseed oil has been used to finish wood for centuries. Unless it is applied witha shellac or varnish base, it penetrates the wood rather than creating a membraneover it. It is this penetration that I feel enhances the wood's grain and color, andaccelerates the development of a natural patina, which is caused by exposure tosunlight and air. The color that is created, I feel, is far richer and more honest thanany pigment that comes out of a can. You just have to be a little patient. You alsohave to be sure to start with a well-prepared, polished piece. In many shops, a finishserves to conceal flaws. I believe that a piece should be virtually defect-free beforeyou begin to apply a finish.

There are three major risks associated with boiled linseed oil. The first involvessafety. Left in a folded rag, linseed oil can combust spontaneously, becoming almostexplosive. Second, the finish affords no protection for wood against water and otherkinds of stains. This is why we apply a paste wax over the oil as a sealant. Third, Iin-seed oildoes not sealwood against moisture penetration the same way lacquers andvarnishes do. Oiled oieces tend to shrink and swell with the seasons more than paint-ed or lacquered pieies do. So in designing furniture, this expansion has to belakeninto account.

The principal advantage of a finish like linseed oil is its repairability. Scratches, burnsand chips can be sanded and polished with the oil. In a short time, the color will comeback and you won't even know it was affected. But if a membrane finish-especiallyone applied over a stain-is chipped, scratched or burned, more often than not it hasto be entirely refinished.

Thomas Moser is president and co-founder of ThomasMoser Cabinetmakers, headquartered in Auburn, Maine.

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INTRODUCTION

Prew Savoy on

THE,CRAFT ETHIC

he piece I am working on in the photograph is a Sheraton-sryle, two-drawer worktable, typical of early l9th-CenturyAmerican furniture building. Knowing how

to apply the appropriate finish takes a good appreciation of furniture style. You haveto approximate the original as closely as possible-in color as well as in topcoat com-position. The best way to get onto the right track is to study furniture styles as thor-oughly as you can. Talk to people experienced with period pieces-museum curators,serious collectors and restoration or conservation craftsmen. They are usually verywilling to share technical information. Also try to see as many original examples aspossible.

For this piece, I selected natural and chemical dyes to make the color appropriateto its history. The table is made of cherry with a figured veneer applied to the drawerfronts. Two different combinations were used: logwood extract (a natural dye) andpotassium dichromate (a chemical mordant) on the veneer; and lye and walnut crys-tals on the cherry.

For the topcoat, I padded a 3-pound-cut orange shellac on the wood. I like usinga pad made up of a wool interior and a linen exterior, but other finishers prefer pol-ishing cloths-perhaps because good-quality linen is hard to find. The technique iscalled French polishing, but the term can be misleading. There are several ways to applya French polish, some using pumice and oil to fill the pores of the wood completely,providing a mirror-like finish. That is not always appropriate for all American pieces.

I trace my interest in fine furniture back to my childhood and my parents who werecollectors themselves. As an adult I spent two summers workins with a boat builder.and much later studied with George Frank in China. When I iarted collecting finefurniture, I couldn't afford the pieces I liked, so I learned to build replicas instead.

I believe that cabinetmakers should consider themselves as caretakers of a sort.building something that will be passed down from generation to generation. You needto develop what I call a"craftethic." You have to love what you do, not for the resultor for a wage, but simply for the sake of finding the finest way of doing each step.

Prew Savoy specializes in furniture finishing andrestoration. He also teaches wood finishing at theOlde Mill Cabinet Shoppe inYork, Pennsylvania.

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SAFETY

f, inishing can be a dangerous businessI' if vou are not well informed andproperly prepared. From wood fillers towaxes, polyurethane varnishes and tungoil, finishing products frequently dependon toxic organic solvents to do theirwork. Without the proper safety gear andprecautions, short-term exposure to thesesolvents can result in irritation to theskin, eyes and throat, as well as dizziness,headache, nausea and shortness of

breath. Longer-term exposure posesmore potential risks; some effects maynot be apparent until you have used thesubstances for months or even years.

In addition to the health risks, mostof these solvents are flammable. Someoil-derived oroducts like linseed oil cancombust sDontaneouslv at room tem-perature iithe vapors are sufficientlyconcentrated. When vaporized in a smallenough concentration of air, a small

quantity oflacquer thinner can cause alife-threatening explosion.

All this is not to suggest that workingwith finishing products has to be dan-gerous-only that it can be if you take acavalier attitude towards the risks. If youspray finishes, consider buying a spraybooth (page.13) or constructing a sprayroom ofyour own (page 102). Asmost ofthe harm from organic solvents comesfrom inhalation, wear a dual-cartridge

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Safety goggleaUae when eprayin4 a finieh;

D ual-ca ftridge reapiratorUae when oprayin4 a finiah or working withchemicale; rnterchanqeable filtere and car-tridqee ?rotect aqainet epecific hazarda,Cartridgea purify air contaminated withtoxins ao they are inhaled, then expelthem throu4h exhalation valve; ftlterprevento inhalation of duat

theae vented go7glee pre--vent finiahinq fumea fromirritating the eyeo

Neoprene rubber gloveaUae to protect the akinwhen oprayin1 or mixinqcauatic fi niahinq producta;o n u g -fitt i n q a u rq eo n' egloveo are auitable formoat other finiehin4 taeke

Claaa ABC flreertinguiaherFor puttin4 out asmall frre in the ehop

Rubber apron

9teel waate dis-poaal containerFor temporaryaafe diapooal ofaolvent-eoakedraqa; dampen ra7awith water firat

Frovidee protectionwhen workinq wiLha wood bleach orchemical etain

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SAFETY

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respirator (page 14), particularly ifyouare spraying or willbe exposed to fumesfor more than an hour. To Drevent eyeinjury wear saiery goggles, und don rub-ber gloves when working with caustic ortoxic fi nishing products.

Whenever possible, choose a productthat combines the finish you want withlow volatility and toxicity (page 19).Work with the windows oDen and use acertified spark-prooffan to keep the airmoving. This will help prevent the fumesin your work area from reaching a toxicor flammable level. If you experiencedrowsiness, fatigue, headache, blurredvision, weakness, numbness, irritation ofthe eyes, skin or throat, shortness ofbreathor a loss of coordination while finishing,stop immediately and leave the workarea until the symptoms clear. After-wards, ventilate the work area thorougfrlyand use a different finishing product.

SAFETY TIPS

. Do no t ea t , d r ink o r smokewhen us ing f in ish ing produc ts .

. Keep f in ish ing produc ts awayf rom ch i ld ren .

r Avo id exposure to o rgan icso lvents i f you are pregnant o rbreast-feed i ng.

o Ins ta l l a t leas t one smokedetec tor on the ce i l ing o f yourshop above po ten t ia l f i re hazards ;keep a fu l l y charged ABC f i reex t ingu isher nearby .

. Never s to re so lvents o r chemi -c a l s i n u n m a r k e d c o n t a i n e r s .Chemica l so lu t ions shou ld a lwaysbe s to red in dark g lass ja rs tos h i e l d t h e m f r o m I i g h t , w h i c hmay change the i r compos i t ion .

r Do not f lush used solvents downthe drain. Consult the Yellow Pagesto f ind ou t who hand les chemica ld i s p o s a l i n y o u r a r e a , o r c h e c kwi th your loca l f i re depar tment .

SPRAYING SAFELY

Using a spray boothSpray ing any f i n i sh ing ma te r i a l p roduces po ten t i a l l y t ox i c o r f l ammab le vapo rs , o rboth. Even the fumes resul t ing f rom spraying water-based res ins wi th lower organicsolvent counts can be hazardous unless they are proper ly vent i la ted.

A sp ray boo th makes sp ray ing c leane r and sa fe r , r educ ing hea l t h haza rds bycon ta in ing the ove rsp ray and fumes , t hen f i l t e r i ng and exhaus t i ng t hem. The rea re d i f f e ren t mode ls des igned fo r d i f f e ren t sp ray ing app l i ca t i ons . They range i ns ize f rom complete rooms to por table models l ike the one shown above, which maybe your best bet i f space is a pr ior i ty in your workshop or i f you only spray smal lp i eces o f f u rn i t u re .

Because o f t he t ox i c and vo la t i l e na tu re o f mos t f i n i sh ing p roduc ts , a l l sp rayboo ths mus t mee t Occupa t i ona l Sa fe t y and Hea l th Assoc ia t i on (0SHA)gu ide l i nesIn some s ta tes , sp ray ing i s i l l ega l i n u rban a reas un less you have a p rope r l y bu i l tspray room (page 102).

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SAFETY

USING A RESPIRATOR

.) lnstalling filtersL Use dust f i l ters in conjunct ion withrespirator cartr idges i f you are sandingchemica l l y t rea ted wood or app ly ing f in -i shrng mater ia ls such as she l lac , lacqueror nonwater-based stains. Choose the appro-pr iate f i l ter for the task at hand, then f i ta filter into each retainer (rrghf). Snap theretainer onto the cartrrdge.

'l lnstalling the cartridgesI Wear a dua l -car t r idge resp i ra to rapproved by the Nat ional Inst i tute ofOccupat ional Safety and Health (N IOSH)whenever you spray lacquers or varnishestha t con ta in vo la t i le o rgan ic so lvents ,or when you mix chemical stains or workwith ammonia. ( l f you have a beard, youneed a ful l face mask or hood). To instal lthe cartr idges on the model of respiratorshown, screw them onto the inlet valves(/eff). Always buy cartridges in pairs,and keep track of the hours they havebeen used.

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Testing the respiratorPlace the respi rator on your face,

wtth the top strap over the crown of yourhead . Pu l l on t he s ides t raps un t i l t hefacep iece o f t he resp i ra to r f i t s snug l y .Test the device by b lock ing the out le tvalve wi th your hand and exhal ing gent ly(above). There should be no air leakagearound the facepiece. l f there are anygaps , ad lus t t he s t raps fo r a t i gh te rf i i l f np rpssa r r r r pn l . acp i hp f : ecn ipnpr J ' i v r s v v

according to the manufacturer 's instruc-t ions, or replace the respirator.

llll illl tlll lll lllj ]ll1 tl]l tlll ljlJ lil llu tlll ull ljll llll ttii llil lllJ1HO? TI?Storing reegiratorcartridgesEven waler vaVorcan deVlete Lhepuri fy inqchemica lsin reepira- ,/.Lor car- ._.,.;,t r idqee. \ ;To extend

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their l i f e, et ore lhecarlrid,qee in a d,ry, airliqhlenvironmenN, such as a plastric freez-

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er baq. Kecord trhe amounN of Nime thecartridgee have been used and replace themafLer eiqht hours of uoe or ae eoon a6 youcan emel l the f in iehinq producL throuqh Ihem.

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SAFETY

CLEANING UP A TOXIC SOLVENT ()R CHEMICAL SPILL

THE RIGHT SOLVENT FOR A SPILL

PRODUCT SPILLED

Mineral sp i r i ts

Turpenti ne

Paint remover

Denatured alcohol

Methyl alcohol

Acetone

Lacquer th inner

Water-based stain or latex paint

0il-based stain

Urethane or polyurethane

Varn ish

Lacquer

S he l lac

Linseed o i l

Tung oi I

Oxalic acid or two-part wood bleach

Lye

Disposing of soiled ragslmmediately open al l doors and windows,ext inguish any sources of heat and turnoff all electrical sources. Wearing a rubberapron, rubber boots, heavy rubber gloves,safety goggles and a respirator, soak upthe spi l l wi th rags or paper towels; theno lace them in a meta l can doub le- l inedwith heavy-duty plastic garbage bags. Adda small amount of water to prevent sponta-neous combustion. You can also spreadthe rags outside and allow the solvent toevaporate before disposing of them. Cleanup any residue with the appropriate sol-vent l i s ted in the char t be low. l f theproduct is extremely f lammable or poiso-nous and more than one gal lon has beenspi l led, leave the work area and cal l thefire department. Otherwise, dispose of thesoi led rags fol lowing the environmentalregulat ions in effect tn your community.

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SOLVENT REQUIRED

Household detergent and water

Household detergent and water

Household detergent and water; or mtneral spirits or paint thinner,then household detergent and water

None

None

None

None

Household detergent and water

Mineral spirits or paint thinner, then household deiergent and water

Mineral spirits or paint thinner, then household detergent and water

Mineral spirits or paint thinner, then household detergent and water

Lacquer th inner

Denatured alcohol (ethyl alcohol) or methyl alcohol

Mineral spirits or paint thinner, then household detergent and water

Mineral spirits or paint thinner, then household detergent and water

Water and baking soda

Water and vinegar, mixed in equal parts

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SAFETY

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BEING PREPARED F()R A CHEMICAL FIRE

Using a fire extinguisherTo cont ro l a smal l , con ta ined f i re , usea dry -chemica l f i re ex t ingu isher ra tedABC. Posit ion yourself safely away fromthe f i re w i th your back to the neares tex i t . Ho ld ing the ex t ingu isher u p r igh ton a leve l sur face , pu l l the lock p in ou to f the hand le ( inse t ) , and a im the noz-zle at the base of the f lames. Squeezethe handle levers together and spray ina quick, s ide-to-side motion (r ight)u n t i l t h e f i r e i s e x t i n g u i s h e d . l f t h eflames spread, leave the area rmmediate-ly and call the fire department. Disposeof burned waste followrng the advice ofthe f i re deoartment. Have the ext in-s r r i s . hp r r pch : rood

Checking a smoke detectorA smoke detector is an essential safetyfeature in a finishing shop. Test the deviceonce every month. First , press the testbutton. Then, blow out a l i t match belowa vent, let t ing smoke enter i t , or hold aflame below it (left). Replace the batteryi f the alarm does not sound for bothtes ts -or i f i t emi ts a ch i rp ing sound,indicat ing the battery is worn.

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SAFETY

DECIPHERING THE LABEL INFORMATI()N

Reading a product labelThe label on a conta iner of f in ish is more than just a t rademarkand a set of inst ruct ions. l t is both the key to compar ing thef in ish 's character is t ics wi th those of other products and a guidet n r r s i no i hp c , r r hc , l : n . p s . : f p l v n t hp shnn The r ^omnns i t e l : he l

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shown above i nc ludes the fea tu res you shou ld l ook f o r whene h n n q r n o : f i n i c . h i n g n r n f , , . - { ^ . , ^ f ^ ^ r ^ . , ; ^ ; + . , - ^ + , ^ ^ \ / ^ ^ - - +

. . . . b r . - u u L L , ) u L i l d ) L U T L T L y r d L i l 1 5 . v v u d r -

i ng , vapo r p ressu re and f l ammab i l i t y . Re fe r t o t he cha r t onn : o p l Q i n d p i p r m r n p t h p l n v i r - r l v n f : n r n d r r r ^ t ' s : r ^ t i v p i n o r c d i -

ents and compare them wi th those of other s imi lar products tohelp you choose the least tox ic f in ish. Fol low the safety precau-

t i nns snec i f i ed nn the l ahe l t o se t r r n t he n rone r ven t i l a t i onand work ing condi t ions, and fami l iar ize yoursel f wi th the f i rs t a idinst ruct ions in the event of an accident .

Some s ta tes a l l ow the use o f T rade Sec re t Reg i s t r y num-he rs f o r a n rod r r c t s i np red ien ts t o n ro tec t na ten ted chemica lf o rmu las . l f you f i nd t he i n fo rma t i on on the l abe l t oo vague ,r e q u e s t a l V l a t e r i a l S a f e t y D a t a S h e e t ( l v l S D S ) f r o m t h em a n u f a c t u r e r i f o n e i s a v a i l a b l e . A n M S D S w i l l e x p l i c i t l yde ta r l t he p roduc t ' s haza rdous i ng rs l i gn l t as we l l as p recau -t i ons f o r sa fe hand l i ng and use .

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lnhalation warnin4lndtcaLee 1,ha1, Lhe prod-uc1; te exLremely haz'ardous durinq prolongedexpoeure; caut ioneaqainef inLenLionala h " a e n f l h e n r n , ' l t t r l

Emergency/Firat aidproceduree'gpectfiee

immedtaLeacLion Lo be Laken in anemerqency involvinq ekinor eye conLacL, inhala-tion or inqeel,ion

VOC (Volatile OrganicCompound) ratingA meaEure of Lhe amounLof volaLtle orqantc com-pounda in Lhe producL, inpercenl,, grame per literor pounde per qal lon

Vapor preoourelndicaLee Lhe force exerted byevaporaLed vapo16 on the aLmoe-phere dtrect ly above Lhe l tqutd,meaeured in milltmel;ere of mercury.The qreater Lhe vapor preeeure, Lhemore volattle Lhe producL

Directione for ueeDetailed inel;ruct,ione on howLo uee Lhe product, tncludin4puiace preparat ion, mir inqquant tr iee. appltc2Ti611 9"16-niquee and clean-up

Product i ncom patibilityA ltat of frntehtnq productol;hat; are chemtcally tncom'pattble wt1;h the product

9afety precautionalneLruct;tone for eafe han-dltn7 and etora7e oftheproduct, i ncl ud in q prapervenLilaLron and warntnqe,7ne of prol6n4ed erpo-eure 1;.o fumea

P rod u ct identificationThe Lype of product andthe brand name 7iven by1,he manufact.urer toidenLtfy Lhe producL

WarninglndicaLes wheLher Lhen r n ) t r r f i a r n r r n a i t t e

flammable or Loxtc

Aative ingredientsIndtcatea the common and/or chemtcalnamee and proporl,rone of bol,h volatrleand non-volaLtle in4redienLe tn 1,he prod-uct, euch ae reetne, eolvenLs. driers andflatLenere: aleo tndtcaLea wheLher LheeolvenL is aenatt ive to l iqht and phoLo-chemically reacLtve, whtch can crealieatrbarne pol luLant e

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Page 21: The Art of Woodworking - Wood Finishing

SAFETY

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CHOOSING A SAFE FINISH

Fin ish ing chemis t ry has changed rad ica l l y in recent years .The most signi f icant advance has been the development ofwater -based f in ishes in resoonse to bo th the hea l th r i sksposed by so lvents and c lean-a i r leg is la t ion tha t l im i ts thepercentage of V0Cs, or volat i le organic compounds, in sol-vent-based f in ishes. Most of these regulat ions are pr imari lyintended for f urni turemakers who use more than one gal lonof f in ish per day, yet industry experts predict that by themid-1990s, VOC-compl ian t f in ishes w i l l be the ru le ra therthan the except ion for everyone in the United States.

Inha la t ion is the most common way tha t so lvents a reabsorbed into the bloodstream, but toxins can also be ingest-ed from food and beverages lef t in the shop. Others can beabsorbed d i rec t l y th rough the sk in o r even by swa l low ingvapors in sa l i va .

ln their most poisonous form, solvents can cause damageto the central nervous system and respiratory tract. Methylene

Toxtc sotvENTs

FINISHING PRODUCT

Wood f i l ler (paste and l iqu id)

Sta ins (ani l ine, wip ing, NGR, gel and g laz-ing stains; color pigments)

Shellacs (white and orange)

Lacquers (spray and brush, sanding sealers)

Lacquer th inner

Rubbing o i ls (Danish o i l , ant ique o i l )

Drying oils (boiled l inseed oil, polymerizedtung o i l )

Varnishes (tung oil varnish, spar varnish,varnish stain)

Polyurethanes (poly varnish, urethane starns)

Lacquer/varnish removers

Waxes (paste wax, furniture wax)

ch lo r ide , fo r example , i s suspec ted o f be ing a carc inogen,whi le some glycol ethers have been l inked to bir th defects.Keep in mind , however , tha t the hea l th hazards o f anyf i n i s h i n g p r o d u c t d e p e n d o n a n u m b e r o f f a c t o r s . M o s tproduc ts on the marke t a re ac tua l l y ben ign when usedon ly on occas ion , and cou ld on ly be cons idered po isonousi f swa l lowed d i rec t l y . Some can even be made non-t o x i c ; s h e l l a c i s c o m m o n l y u s e d a s a n i n g r e d i e n t i nc o n f e c t i o n e r s ' g l a z e .

When choos ing a f in ish ing produc t , be aware o f thecombina t ion and concent ra t ion o f o rgan ic so lvents in i t smakeup, par t i cu la r ly i f you in tend to use the subs tancefor extended periods of t ime; prolonged exposure may behazardous . The char t be low l i s ts the so lvents conta ined ina var ie ty o f f in ish ing produc ts and eva lua tes the re la t i vetoxici ty of each one. Always choose the safest product forthe job a t hand.

SOLVENT

Petroleum naphtha*, mineral spirits*, acetone**, methyl ethyl ketone**, methylisopropanol**, isobutyl ketone***

Ethanol*, mineral spirits*, toluene***, xylene***, methanol***, glycol ethers***

Ethanol*, methanol***

Acetone**, methyl ethyl ketone**, isopropanol**, methanol***, xylene***, glycol ethers***

Acetone**, methyl ethyl ketone**, isopropanol**, glycol ethers***, toluene***

VM&P naphtha*, turpentine**, toluene***

Mineral spirits*, turpentine**

Mineral sp i r i ts* , VM&P naphtha*

Mineral so i r i ts* . to luene***

Acetone**, xylene***, methanol***, methyl isobutyl ketone***, toluene***

Petroleum naphtha*, turpentine*** Safest product** Mildly hazardous product*** Product to be avoided if possible

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Page 22: The Art of Woodworking - Wood Finishing

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Page 23: The Art of Woodworking - Wood Finishing

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ened edge, however, which can scratchthe wood as badly as coarse sandpaper.

Sanding with successively finer gritscompletes the surface preparation. Forhand-sanding a fairly smooth surface, atypical progression is 150 grit, followedby220 and then 280 grit. (lfyou did notsmooth the wood with a cabinet scraper,you might need to start with 80 or 120grit.) Never skip an intermediate grit oryou will leave scratches in the wood thatthe finish will magnifr. With an orbitalsander, use the same grit sequence; planon hand-sanding with the final grit toremove anywhorls. After final sanding,

Despite a modern blade adjustment mechanism that enables the tool to slice offpaper-thin shavings, this smoothing plane retains the handcrafted quality of a traditionalhand tool. Producing smooth surfaces is a crucial step in finishingfurniture.

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PREIARINGTHESre

ld-time wood finishers smoothedwood with sharkskin and rush.

filled its pores with plaster of Paris andpulverized brick, colored it with mate-rials such as iron filings and walnutshells. and finished it with secret com-binations of oils and beeswax. Modernfinishing techniques are mundane bycomparison, but the object is the same:to bring out the beauty of the wood.Whether this means a glassy film on thesurface of the wood or a finish that soft-ly glows from within depends on thetype ofprotection the wood needs andthe effect you wish to achieve. Becausetaste is involved, there is no single right answer to every finishingquestion. But all professional-quality finishes have one thingin common: painstaking surface preparation, which readiesthe wood to accept the finishing materials.

The amount of time you spend on surface preparation andthe tools you use depend in'large part on your'work habitsand your wood. Surfaces speckled with dried glue obviouslyrequire more work to smooth. Loose knots, splits and otherdefects need repair prior to finishing; so does every dent andchisel nick. The wood probably has jointer and planer marks,which you can remove with shallow cuts using a smoothingplane. The plane must be properly adjusted and sharp, so it cutswood fibers rather than tearing them and roughening the sur-face. Ifthe wood has an irregular pattern, so you cannot avoidtearing the grain as it changes direction, substitute a cabinetscraper-a thin, flat piece of steelwith a burred edge. (For ulti-mate smoothnes of straight-grained wood, use both the smooth-ing plane and cabinet scraper.) Cabinet scrapers take practiceto sharpen and use, but once mastered they can substantiallyreduce your sanding time. Beware of an improperly sharp-

Among its many uses, the hand scrapercan help clear away dried adhesiveafter gluing up a carcase or drawer.

you may wish to "raise the grain" and then resand, to removethe whiskery fibers that might otherwise pop up through thefinish on the first humid day. This step is essential when apply-ing any material with a water, rather than solvent, base.

Whether or not you fill the pores of the wood is again amatter of taste. Ifyou like a natural-looking finish that allowsyou to "read the wood grain," do not use filler. Close-grainedspecies such as pine and cherry do not require filling in anycase, but ifyou want a glassy finish on an open-grained species,such as oak or mahogany, you must fill the wood.

A wash coat may be applied to the wood before or afterstaining-or not at all ifyou are applying a penetrating oil fin-ish. A wash coat can be nothing more than a half-and-halfsolution of your final finish and the solvent recommended byits manufacturer (for lacquer, use sanding sealer). The point ofusing a wash coat is to prevent the wood from uneven or exces-sive absorption of finishing materials. When applied beforethe final finish, the wash coat keeps the wood from drinking upthe finish, thereby reducing the number of coats required tobuild up the proper thickness.

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Page 24: The Art of Woodworking - Wood Finishing

TOOLS AND ACCESSORIES

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Honing guideand angle jigFor honinq planebladee. Device holdablade at appropnaLeanqle for honinq abevel; rotatinq thewheel on Lop ofthe ji4 eete angleobef,ween 15o and 35o

9moothing plane IIttIIIIII

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For smooLhinq wood aurfaceewith the grain, ueually prior toscrapin4 and oandinq. BlademuEL be aharpened and prop-erly adjuated before uee

Grinding jigFor holdin4 plane bladeain aliqnment with grindin4wheel durinq aharpeninq

Tri-burniaherUaed to form amall burr, or hook, oncuLtrn4 edqeo of ecraper after honin4;

Mill baetard file

File alampHol dE fil e perpend icul a rto cutting edqe of ocraper

For equartnq cuttin4 ed4eoof ecrapero prior Lo honin7and burniehinq them

durtnq eharpeninq ofocra per, enau ri n q atra i 7htand square eaqe

Block planeFor omoothin4 end4rain and chamferedau r-facea; ueually ueedwith one hand

Combinationaharpening atoneFor eharpentn4 plane bladea.Coarae side removee metalquickly; fine atde creategemoof,h ed4e. Lubricatedwtth water or orl dependingon the type of stone

Hand ecrapereKect a n g ul a r acra per am ooth aflaL aurfacea: curved moaelework well on contoured eur-facea, moldinqa and epindlee

Abraaive padeAn alternattve to eandpaper forsmoothinq wood aur-facee and abradinqinf,ermediate finieh coata by hand;abraaive particlee of aluminum oxtdeand etlicon carbtde are bonded to evn-LheLic fiber pade. Laat lonqer thansandpaper; can be waehed and reused

Cabinet scraperFor amooLhinq wood aur-facea, typicallyafLer planing; well auited far levelinq knoteand cuLting away dried qlue. Elade ocrapeaa paper-Lhin ehavtng from aurface: hastwin handlea for 4reater convenience andcontrol than hand acraper

combtnes round, trianqular andoval burnishera in one tool

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Page 25: The Art of Woodworking - Wood Finishing

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IPREPARING THE SURFACE

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Eelt eanderTower eander ueed to removeatock and eliminate flawafrom wood aurfacea. andfor amoothinq. Iandinqbelta available in qritefrom coarae to fine

5t'eel wool9pectally made woodworkinq eteelwool ia oil-free and featurealonqer etrande than etandardvarietiea: leeo likely to

Cont'oured eanding bloakHolda aandpaper foramoothinq curved andi rreq ula rly aha ped eu r-facea by hand: featurea anarrow arde for reachin7into nqht epota

Random-orbit sanderFower sander uaed for fine amooLh-inq and removinq awirl marka leftby belt or orbital aander; ideal forcontoured aurfacea

Orbitalpalm eanderFower eanderfor omoothinqaurfacee thatare difficultto reach with6rqer 9anaer

FIat aanding blockHolds aandpaoer tosmooth flat aurfaceaby hand

Alcohol lamp and burn-in knifeUaed to apply ehellac atick todamaged areag on wood aurfacea;flame from lamp heato knife, whichrn Lurn melLE ahellac, drippin4 it.onto aurface

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Grindertharpenin4 wheelGan be uaed toregrind bevela onplane bladee

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Page 26: The Art of Woodworking - Wood Finishing

PLANING

f hoosing the best way to smooth a\-r wood surface is a matter of indi-vidual preference. There are no ordainedsteps or prescribed rules. Some wood-workers plane and then sand; othersplane and scrape before sanding.

Whichever sequence you decide tofollow, the object is to produce a surfacethat is as smooth as glass and just as flat.This section of the book explains theuse of a smoothing plane to begin theprocess of preparing a wood surface toaccept a finish.

A well-sharpened blade in a proper-ly adjusted plane can shear offfine shav-ings of wood. You can make all theadjustments with only a screwdriver,despite the plane's apparently compli-cated design (below).

Plane blades require regular sharp-ening. Although you can hone a bladeby hand (page 26), a grinder is the best

tool to bring a cutting edge to peak per-formance. For a nicked blade or an oldout-of-square one you wish to salvage,

Planing the edges of a workpiece with asmoothingplane-also known as edgejointing-is usually done before plan-ing the faces. This allows you to remove

any blemishes from the faces left bythe jaws of a clamp or a vise.

square its end (page 25, step 1).For anew blade or one that has had its bevelworn away, hone a new bevel on the cut-ting edge (step 2). To maintain a keenedge, hone the blade frequently on asharpening stone (step 3).

Before using a plane, set the depth ofcut to remove only a thin shaving oneach stroke. Because an excessive depthsetting mayproduce gouges in the workpiece, you should test your setting firston a scrap board. For best results on alarge surface use a long plane; a shortone will be more likelv to follow existing contours.

Set a plane on its bottom when stor-ing the toolto prevent the iron from get-ting nicked by other tools. Occasionallyrub a thin film of light machine oil onthe blade to prevent rust. Once ayear,or depending on the amount of use, takethe tool apart for a general cleaning.

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ANATOMY OF A SMOOTHING PTANE

Cap iron aarewAdjuete offaet diatance betweencutting edqe of blade and end ofcap iron; to avoid blade chatter,

Late ra I a dj u ati n g leve rCentera the blade in themouth of the plane byaettin7 the lateral, oraide-to-aide, poaition ofthe blade

Cap lockHolda levercap in place

Frog adjuetin7 earewTurned to alide frog back and forth; poei-tioned to eet cuttinq edge of blade about1/az inch from front edae of mouth

Lever capAllowa quickremoval of capiron and blade

'la inch io ideal 6ap

Lever aap acrew)ecures lever cap,cap iron andblade to fro4

BIadeAlao known aa olane iron. lnstalledbevel down on fro4; for beat reeulta,ahould barely probrude from mouth

Frog9upporbeblade

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Page 27: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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SHARPENING A PLANE BTADE WITH A MACHINE

1 Squaring the end of the bladeI Use a trv souare to check whether thecut t ing edge o f the b lade is square . l f i tis not, square i t on a gr inder with a roughwheel. With the guard properly posi t ionedand the b lade c lear o f the whee l , sw i tchon the machine. Holding the blade betweenthe index f inger and thumb of your r ighthand, set i t bevel up on the gr inder 's toolrest and advance it toward the wheel untilyour index f inger contacts the tool rest(right). Slide the blade side-to-side acrossthe wheel, pressing l ight ly whi le keepingyour f inger on the tool rest. The t ip of theb lade shou ld s tay perpend icu la r to thewheel throughout the operat ion. Dip theblade in water occasional ly to prevent i tf rom overheat ing. Check the blade forsquare regurany.

r) Creating a hollow-ground bevelZ . Sharpen ing a p lane b lade invo lvesthree steps: creating a bevel on the blade'scutt ing edge, honing another bevel onpart of the f irst one-called a microbev-el- then removing the burr that resultsfrom the honing process. To create thef i rst bevel, c lamp the blade top face upin a commercial gr inding j ig set to createa 30" bevel. Run the cutt ing edge acrossthe wheel as you would for squaring theb lade; the j ig w i l l keep the b lade squareto the wheel (left). Check the cuttingedge periodical ly and stop gr inding whenthe bevel forms (lnsef). As a rule of thumb,

the bevel is correct when mostof the sparks showering tromthe gr inder fa l l on the topface of the blade, rather thanbelow i t .

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Page 28: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

Q Honing the microbevelr-,f Place a combination sharpening stonef ine side uD on a work surface. Nai l c leatsto the table against the stone to keep itf rom moving. One of the cleats should bethe same height as the stone and 4 to 5inches Iong; this wi l l a l low you to use theful l length of the abrasive surface. Clampthe blade in a commercial angle-sett inghon ing gu ide w i th the beve l touch ingthe stone. Saturate the stone with theappropriate I ubr icant-ei ther water ora l ight oi l -unt i l i t pools on the surface.Then, holding the honing guide, s l ide theb lade back and fo r th f rom end to endalong the stone (lefil, applying moderatepressure until a microbevel forms (insef).

Continue until a burr-a thin ridgeof metal- forms on the f lat faceof the b lade. Then lap the bur ras you wou ld when sharpen ing aplane by hand (sfep below).

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SHARPENING A PTANE BTADE BY HAND

[apping the bunClamp the blade in a commercial guide(step above) and grind a 30" bevel usingthe coarse side of the stone. Then reoosi-t ion the blade in the guide and turn thestone over to hone the microbevel. Toremove the burr f rom the blade-aprocess woodworkers call "lapping" theburr-remove the blade from the honingguide and saturate the stone once again.Holding the blade flush on the stone, bev-el s ide up, move i t in a circular pat iern onthe stone (righil unlil the flat side of thecutt ing edge is smooth to the touch. Afew strokes should suff ice to el iminatethe burr. Test the sharpness of the cut-t ing edge on a piece of paper; a sharpblade wi l l s l ice a sl iver from the edse.

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Page 29: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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ADJUSTING A PTANE

' l Positioning the cutting edgeI Loosen the lever cap screw and remove the blade assem-bly- inc luding the lever cap, cap i ron and b lade- f rom theplane. Then loosen the cap i ron screw and s l ide the cap i ronon the face of the b lade to leave a gap of about %o inchbetween the end of the cap i ron and the cut t ing edge of theblade. T ighten the cap i ron screw. Next , p lace the b lade

Assessing a plane blade's cutting edgeNo matter how wel l i t is adjusted, a dul l or poorly sharp-ened plane blade will do a poor job of smoothing the woodsurfaces of your furniture. Moreover, its condition will onlydeter iorate i f you persist in using i t , losing i ts beveledcutt ing edge and possibly even going out-of-square, asin the blade shown (far /eft). Such a blade would needto be squared and sharpened on a gr inder. A wel l -sharp-ened blade (near left) has a vrsible bevel and microbevel,making i I a razor-sharp cutt ing implement. This bladeneeds only an occasional honing on a sharpening stone.

assembly in position on the frog. The gap between the frontedge of the blade and the front of the mouth should be aboutt/rc inch. lf not, loosen both frog setscrews about 1Z turn,then turn the frog adjusting screw with a screwdriver to setthe proper gap (above). Lock the blade assembly in position.

Lever cap ecrew

Froq eetecrew

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Page 30: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

r) Centering the blade andZ- setting the depth of cutHo ld ing the p lane as shown, sh i f t thelateral adjust ing lever to one side or theother to center the cutt ing edge in themouth. To set the cutt ing depth, turnthe depth-of-cut adjustment knob sothat no more than aboul rhz inch of thecutt ing edge protrudes from the mouth.Check the depth of culby eye (right),then conf i rm the se t t ing by mak ing atest cut on a scrap board. The shavingsshould be paper-thin; the f iner the cut,the more t ransparent the shav ings .Adjust the cutt ing depth, i f necessary.

SMO()THING WITH HAND PLANES

Using a smoothing planeGuide a hand p lane a long a wood sur face wi th smooth, evenstrokes. Always cut with the grain of the wood; planing againstthe gra in wi l l tear the wood, rather than shaving i t o f f c lean-ly . l f you cannot determine the or ientat ion of the gra in, l ight-l y s l i de t he p lane pa ra l l e l t o an edge i n one d i rec t i on , t henrepeat in the opposi te d i rect ion. The cut t ing edge wi l l chat-ter or catch on the wood f ibers when i t is cut t ing against thegrain. l f the gra in or ientat ion changes on the sur face, swi tchthe d i rect ion of your s t roke to fo l low the gra in. To smooth asur face such as a tabletop, move the p lane back and for thusing a series of straight passes that slightly overlap, as shownin t he d iag ram a t r i gh t . When pu l l i ng t he p lane back a f t e reach forward st roke, t i l t the tool to one s ide to l i f t the cut-t ing edge c lear of the sur face.

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Page 31: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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Smoothing a faceSecure the workpiece face up on a worksur face . 0nce you have or ien ted theplane with the wood grain, l ine up yourshou lder and h ip w i th the too l to he lpyou main ta in fu l l con t ro l o f the cu t .Gripping the plane with both hands asshown, push the tool along the surfaceaway from your body. Apply f i rm andsus ta ined pressure dur ing the s t roke ,pressing down on the front of the planeat the start of the pass. Once the planeis completely on the surface, even outthe pressure, shi f t ing the pressure tot h e r e a r n f t h e n l a n e a i t h e e n d o f t h e

stroke. Examine the shavings as you workand adjust the cufting depth if you want af iner cut. Keep planing unt i l the surfacebecomes shiny and smooth to the touch.

Smoothing end grainUse a b lock p lane to smooth the ends ofa workpiece. There are two ways of p lan-ing end gra in, both involv ing two stepscalculated to avoid tearout at the edges.For e i ther method, secure the workpieceend up . I n one me thod , beg in a s t rokea t one edge o f t he boa rd , gu id ing thep lane a long the su r face un t i l t he b ladeis about halfway across the end (left).

Repeat the process f rom the opposi teedge. In the second method, s tar t bycu t t i ng a chamfe r a t one edge o f t he

boa rd , ho ld ing the p laneat an angle to f la t ten thecorner (inset). Then makea pass across the ent i re end,beginning the st roke at theother edge.

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Page 32: The Art of Woodworking - Wood Finishing

SCRAPING

Q craping wood surfaces is an inter-rJ mediate step between planing andsanding. A sharp scraper can removehigh spots, tearout and glue lines,smooth a surface, and clean up marksleft by a plane. The tool is inexpensive,easy to use and relatively simple to sharp-en. Tho commonly used types are thehand scraper-a single blade of steel-and the cabinet scraper, a blade mount-ed in a metal or wood body thatresembles a spokeshave. This implementfeatures winged handles for two-hand-ed pushing or pulling.

Scraper blades are made from thinsheets ofspring steel and sharpened toform a cutting edge. They are availablein different thicknesses, depending onthe work you want them to perform.Thick scrapers are suitable for heavy cuts;light scrapers are used for finer work.Unlike a plane blade, the scraper has ahook-a small flare along the length ofthe cutting edge (inset, page 32).Thehook's cutting action allows the scraperto be pulled or pushed in any direction,

SHARPENING A SCRAPER

so you can reach corners and tight spotsinaccessible to a plane.

A scraper's cuiting edges dull quick-ly and require regular sharpening, whichinvolves filing, honing and burnishing.The size of the scraper's shavings signalits condition: the duller the blade, the

Properly sharpened, a scraperwill produce finer and shorter

shavings than a plane.

smaller the shavings, until finally the toolproduces only sawdust.

Most new scrapers need to be filedsmooth before use. It may help to applya little lubricating oil on the cutting edgeofthe scraper before burnishing, but becareful with the oil: If it gets on yourhands orbench it could end up stainingthe workpiece.

Apart from maintaining the cuttingedges of a scraper, keep in mind that thetool will perform well only ifyou hold itat an angle to the wood surface and pushor pull itwhile applying a fair amount ofpressure close to ttre cutting edge. Ifyouhold the scraper almost perpendicularto the surface and apply healy pressure,the tool will quickly remove wood, butit may also gouge, dent or scratch thesurface. Held at more of an angle, thescraper removes less wood, but producesa smoother surface. One method of find-ing the right angle is to hold the toolalmost parallel to the work surface;beginscrapingwhile gradually raising the angleof the blade until it bites into the wood.

1 Filing the edges squareI To file off the existing hook on ascraper, clamp the tool in a vise withone long edge facing up. Holding asharp mill bastard file firmly with bothhands as shown, make several passesback and forth along the edge of thescraper, exerti ng moderate downwardpressure until the bun disappears andthe edges are flat. To remove fil ings,periodical ly tap the f i le on a f i rm sur-face or use a file card. Turn the scraoerover and repeat the process for theother edge.

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Page 33: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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fiu |lt filr ilil llt tljJ llil llil tl]J fill ltJ illl lllt lll tlll lll filt l]ll5HO7 Tt?Uoing a file clampDeeiqned No hold a f i leperpendicular to the edgeof a ocraVer, a f i le clampmakes it, eaey tro removehooks and f i le oLraightedqee on Ihe trool .To usethe f i le clamp, secure theocra?er in a viee alongwilh a wood block on oneeide to keep i t , r iq id. lneerLIhe f i le in the c lamp andf ix i t in p lace uo inq lheLhumbscrewe on Iop of thei m p l e m ent . 7o EiL i o n Lh e c l ampon lhe edge of the ecraVer and file lhe ocraVer'e ed4e unlil it,feele sharp, takinq care not Io cuX youroelf when NeeLinq.

r) Honing the edgesL Secure a combinat ion sharpeningstone f ine side up to a work surface withcleats and lubr icate i t as you would whenhoning a plane blade (page 26) Holdingthe scraper f lat against the stone, rub theface on the stone with a circular motion(left). Apply moderate pressure and con-t inue unt i l any roughness produced by f i l -ing disappears. Turn the scraper over andrepeat for the other face. To complete thehoning, hold the scraper edge down andsl ide i t back and forth diagonal ly acrossthe stone unt i l the edge is smooth withsharp corners. Repeat for the other edge.

Page 34: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

Q Burnishing the edges to start a hookr.,l Place the scraoer f lat on a worksurface with the edge to be sharpenedextending off the table. Holding a bur-nisher at a sl ight angle to the scraper,make several passes back and forthalong the edge ( lef t) , applying strongdownward pressure to start turningover the edge into a hook. Burnish theother cutt ing edge the same way; turnthe scraper over and burnish the edgeson the other face.

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Completing the hookSecure the scraper edge up in a vise

Hold the burnisher almost perpendicularto the edge and run i t along the edge inone direction until the edge swells slight-ly, turning outward on one side (right).For best results, apply moderate pres-sure . Then ho ld the burn isher so tha tt h e h a n d l e i s a t a 1 0 ' t o 1 5 ' a n g l eabove the edge of the scraper and con-t inue burn ish ing un t i l the edge tu rnsover. Repeat the process to form a hookon the other side of the edge (inset), thist ime holding the handle with your otherhand. The greater the pressure you apply,i h o h i o o p r t h p h n n k

Turn the scraper overand burnish the oppo-s i ie edsp Tps i thp . r r i -

t i n o p d o o c n n a n i p n p

of scrap wood, burnish-ing them again, i f nec-essary, until you havethe hook you need forthe job a t hand.

Page 35: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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flll llll llll llll llll ru lll1 ilil llll llll lllt llll ull illl llll llll lllt lllt1HO? TI?Using a variable burnisherl ,oldinq a burnieher aL the r iqht.ao ld tnq a Ourn tener a t tangle for turnin4 over ahook on a ocraVer ie noeaoy laok. One answerie a commercial j iq Ihalprovideo Vrecioe controlof the burniohing anqle.The actual burnisher iea carbide rod mounledwilhin Lhe body; a knobonNheNop ad juo toNheanqle of Nhe rod belween Oo and 15o.Io useNhe burnieher, oecure the ecraVer in a viee andLne aurnt?ner, ?ecure T,ne Scra?er tn a vt6e ana :f i I i te b lade in the burnisher 'e e loN: runninq the burnieherback and f or\h alon4 the blade wilh moderale downward

?re6oure creaLee a hook of Nhe apVropriaLe an4le.

SMO()THING A SURFACE WITH A HAND SCRAPER

Using a hand scraperSecure the stock to a work surface.Standing at one end of the workpiece,curl your fingers around the front of thescraper and press on the back with yourthumbs to make the tool bow sl ight lyoutward. Tilt the scraper forward about20' from the vert ical and scrape thesurface in the direction that the bow isfacing (left). lf the cutting edge doesnot bite into the wood properly, adjustthe angle of the tool s l ight ly. Work ata s l igh t ang le to the gra in , app ly ingmoderate pressure and making long,f luid, overlapping strokes. At the endof each stroke, lift the scraper off thesurface before stopping. You can alsopul l with the scraper, but be sure toflex the bow toward you.

Page 36: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

SMOOTHING WITH A CABINET SCRAPER

1 Adjusting the bladeI lnstal l the blade in the scraper with the hooked edgefacing forward and protruding t/zz inch from the sole of thescraper. Lock the blade in place by turning the two thumb-screws on the front of the scraper clockwise (abovd. fhenbow i t s l igh t ly by tu rn ing the thumbscrew tha t p ressesagainst the center of the blade at the back 6f l ls scr:ner

r) Using the scraperZ Secure the workpiece. Then, standing at one end of thestock and holding the scraper f i rmly with both hands with thehook facing away from you, push the tool with moderate pres-sure along the surface (abovd. At the end of each stroke, liftthe scraper off the surface and turn the tool upside-down iodislodge the shavings and prevent the blade from clogging.

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ltlj ull lllr l]l] llll llll llll llrl llll lll llll llll fifi llll r]l] llrl llll ilIl1HO? Tt?Uoing old oara?er bladesto cut half-blind dovet aileYou can aet eorne moremileage ou| of an oldocra?er by uoin7 itNo complele lhe eawcuNe made to fashionhalf-blind dovelails.Tlace lhe blade in thekerl and tap il witha hammer unLi l i t ,reaches the shoulderl ine of the ioinLThie wi l l make iNeaeier Lo finieh Nhe cut with a chisel,

Page 37: The Art of Woodworking - Wood Finishing

SANDING

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII

Q anding is the final stage in smooth-J ing a piece of furniture and is alsoindispensable in eliminating any blem-ishes left by planes and scrapers. Bothtools sometimes leave marks and ridgeson wood surfaces. They can also com-press wood fibers and close the pores inthe wood, inhibiting its capacity to prop-erly accept a finish. Sanding as the finalstep opens closed pores, allowing thefinish to penetrate the surface.

A wide variety of natural and man-made sandpaper abrasives are availablefor the woodworker, from natural mate-rials such as flint, garnet and emery toartificial ones like aluminum oxide andsilicon carbide. For most applications, youneed a sandpaperwith hard, sharp-edgedparticles ttrat are not easily dislodged fromtheir paper backing. Garnet, silicon car-bide and aluminum oxide are the abra-sives that best satisfy these criteria.

A typical sanding sequence beginswith a 120- or 150-grit paper, dependingon whether or not you used a scraper(page 30). You may first need an 8O-gritabrasive to eliminate defects or irregu-larities from a surface. Continue sandingwitha220-grit paper, moving to increas-

SANDING FLAT SURFACES

ingly finer abrasives to remove thescratches left by the preceding opera-tion. For a surface that is to receive aglossy finish, you will need to use a paperat least as fine as 320 grit. How high upthe grit scale you climb depends on thefinishing product you intend to applyand the effect you wish to achieve. Keepin mind, however, that polishing a sur-face to a high gloss with an ultra-finepaper maykeep a stain from penetratingevenly. Refer to the chart on page 37 for

Combining the convenience of apower tool with the fine touch of

hand sanding a palm sander readiesa cabinet for a finish.

information on the different sandpapergrades and grits and when to use them.

Apart from selecting the appropriategrit, you also need to choose betweenopen- and closed-coat paper. The abra-sive particles on closed-coat papers cov-er almost the entire surface of thebacking, and are best suited to sandinghardwoods. Open-coat papers havemore widely dispersed particles, cover-ing only 40o/o to 700/o of the backing.These are your best bet for softwoodsbecause they are less prone to clogging bymore resinous wood.

fu shown on the following pages, sand-ing can be equallywell accomplished byhand or with power tools. Althoughhand sanding is laborious, it allows yougreater control over the process, espe-ciallywhen working on contoured sur-faces or in corners and tight spots.

Whichever method you select, youcan judge whether the surface is smoothenough by pulling a piece of fine nylonfabric over the wood; the cloth will snagon rough spots. Then examine the woodunder a beam oflight played across thesurface at a low.angle. The^light willexpose any remalnmg lmperfecuons.

Using a belt sanderClamp the workpiece down and instal la sanding belt of the appropriate grit onyour belt sander. Holding the tool abovethe stock with both hands, switch it onand gently lower it flat onto the surface.Guide the sander from one end of theworkoiece to the other in smooth andstraight overlapping passes that followthe grain of the wood (/efil. Keep thesander f lat and moving at al l t imes unt i lthe surface is uniformly smooth. Avoidleaving the tool on one spot whi le i t isrunning; it can cut into the surface quick-ly, leaving a gouge. Clean up the sand-ing particles (page 42)before repeatingwi tha f iner -g r i tbe l t .

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Page 38: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

Hand sandingAttach a piece of sandpaper of the appro'pr ia te gr i t to a sanding b lock. Gr ip theblock f i rmly and sand the sur face wi ths t ra igh t , ove r l app ing , back -and - fo r thst rokes, apply ing moderate pressureand work ing wi th the gra in of the wood(above, left), Keep the block f lat on thesur face at a l l t imes, par t icu lar ly whenyou reach an end or edge. To smooth asmal l or rest r ic ted sur face, such as thea reas be tween the so ind les o f a cha i ras shown , use a commerc ia l sand ing^ + l ^ t , / ^ ^ ^ , , ^ - : ^ L + l> L t L ^ l a u u v c , r t B r t L , t .

lttl llll illl llil illl l]ll l]lt illl ll[ l]ll llll llt llll illl ilit illt ru ilfl1HO? Tt?Shop-made oanding blockCUI a wood blockthal you canqrip comfortably. On Ihe topface of the block, cuL lwonarrow qrooveo, then cuI twowedqe- ehaped wood obripoNh aI fit, in Lhe qroovee enuqly. Toprovide even eandinq ?reooure, glue a fel|or cork pad t o Nhe boLbom lace of the block.To usetheb lock ,wra? a p iece o f eandVaVeraround it,, inoert Nhe ende inNo lhe qroovee, thentap in the wedgeo to hold Nhe VaVer in Vlace.

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Page 39: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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ABRASIVE GRADES AND GRITS

SANDPAPER

Grade

Med ium

Fi ne

Very fine

Extra fine

Super f ine

STEEL W(lOL

Med ium

Fine

Extra fine

Super f ine

Grit

80, 100, 120

150 , 180

220 ,240

280,320

360 ,400

600, 1200

1

00

000

0000

UsesInitial smoothing; removing shallow depressionsand scratches

I ntermed iate smooth i ng

Final smoothing before applying a f inish

Removing dust part icles and air bubbles betweenfinish coats

F ina l sand ing be fore f ina l coa t o f f in ish ; in i t ia lsanding for high gloss f inish

Rubbing down the f inal coat of high gloss f inish

Light removal of part icles and raised f ibers;smoothing of shal low depressions and scratches

Smoothing before applying a clear f inish

Smoothing between coats of f inish; l ight cleaningand deglossing of a f inish or pol ish

Polishing; waxing

Choosing sandpaperThe range of sandpaper gr i ts in thechart at lef t wi l l serve for almost anyf in i sh ing job . When buy ing sand pa-per , cons ider i t s compos i t ion . A lu -minum oxide paper works best witha belt sander. Choose si l icon carbidepaper in g r i t s above 220 fo r f in ishsand ing w i th an orb i ta l sander .

llu ljlJ llll lll tll illt t]l] llll lllt tll lllj llt lll} ljlt fllt llll illt l]ll1HO? TI?Making a aandpaper auttingboardTo cul sheele of oandpaper quicklyand accuraLely, uee a ohop-madecutt inq board. Screw a hacksawblade to a piece of plywoodwith a washer under eachend to raise i t el iqhNlyoff the Vlywood.TocuT a sand?a?ersheet in half, ,./ ..e l ide i I underthe b lade.Ho ld in4 oneend down,Nearthe other part, of the \eheet off. For a quarEer sheel,mark a l ine paral lel No Nhe bladeNhat,is one-quarLer ofLhewidlh of aeheeX f rom the leelh.Then a l ign lhe endol f,he eheet wilh lhe l ine and lear.

1,r)r \;: li.i'; \rino 'i'

.','*^*

t .-s- od , " c 4

ki**"*":

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Page 40: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

SANDING CURVED SURFACES

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Hand sandingSmoothing contoured surfaces using only sandpaper r iskscreat ing blemishes on the wood or f lat tening out the curveswith excessive pressure. For a shop-made sanding pad thatcan fol low contours without oversanding, wrap a sheet ofsandpaper around a thick sponge that you can comfortablygr ip. Hold the paper around the sponge and sand along thelength of the surface with f i rm pressure.

Using a random-orbit sanderWith i ts compact and pl iable sandingpad, the random-orbi t sander is idealfor sanding contours such as a cabri-ole leg (left). Clamp down the work-p iece and fas ten a sand ing d isk tothe sander 's pad. With the tool c learof the stock, switch it on and lowerthe pad onto the surface. Applyingmoderate pressure, work along thelength of the workpiece in back-and-fo r th passes un t r l the sur face issmooth . Repos i t ion the p iece inthe clamp as necessary to smooth^ : i ^ ^ ^ - + ^ , , " + - ^ ^ ^d u l d u t r r r L ) u r i d u c ) .

Using a sanding b lockSecu re t he wo rkp iece and a t t ach a p iece o f sandpape r t oa commerc ia l con tou r sand ing b lock . On the t ype shown ,the ends o f t he pape r a re p inched toge the r and he ld i n as lo t on t he na r row s ide o f t he b lock . Fo r mos t con tou rs ,sand w i th t he c i r cu la r s i de o f t he b lock aga ins t t he wood(above). For crev ices and other t ight spots, wrap a sheeto f sandpape r a round the b lock , ho ld i t i n p lace and sandw i th t he na r row s ide .

Page 41: The Art of Woodworking - Wood Finishing

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PREPARING THE SURFACE

CONTOURED SANDING BLOCKSmoothing the contours of a piece oImolding evenly without damaging i tscontours is a di f f icul t task with onlysandpaper or a convent ional sandingblock. However, you can use a shortsample of the molding to shape yourown sanding block that correspondsexactly to the surface of the work-piece. Fashioning the block requiresbody f i l ler or model ing rubber, usedto make a mold of the orofile.

To prepare the mold, nail togethera smal l box sl ight ly longer and widerthan the sample molding and aboutr/q inch deeper than the thickest partof the molding. Prepare the f i l ler fol-lowing the manufacturer 's instruc-tions, then fil l about half the box withi t . Lay a single ihickness of plast icwraD over the box. Whi le the f i l ler

is stil l soft, press the molding sam-ple into the box and clamp i t f i rmlyagainst the f i l ler. Let the f i l ler hard-en, ihen careful ly remove the mold-ing sample from the box. Saw offthe ends of the box.

To transform the box into a sand-ing block, stretch a piece of sand-paper abrasive side up across themolded side of the box. Use themolding sample to press the paperagainst the hardened f i l ler, thenstaole the ends to the sides ofthe box.

To use the block, clamp the work-oiece down and slide the block backand forth along the molding (/eff).

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Page 42: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

Smoothing grooves and turningsTo sand narrow grooves in turned pieces such as chair spindles,use commercial abrasive cord. Cut a piece of cord long enoughto extend a few inches on each side and wrap i t around thegroove. Pul l one end and then the other repeatedly to sand halfthe circumference of the groove (above, left). Work from the

opposite side to smooth the other half . To sand turnings orlarger grooves, use abrasive tape (above, right), which is widerthan abrasive cord but handled ident ical ly. Smooth intr icateturnings and moldings using steel wool or abrasive pads.

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r]ll ilI1 ill lltl lltl illl fill tlll lll} ull i]Il ult llll ilIl il1j ilu tjll fit1?HO? TI?Shop-made abraaive tape1anding belNe are an excellenloource of abraeive Lapeo. Thebelbe readily Near in parallelebr ipe, makinq iL eaey toobtain a lenqth of abrasiveof Yhe width you need.) inceuoinq abraoive Nape involveecrooo-qrain oandinq, uoe onlyslrios from fine-arit bells.Coalrser abrasivis may leaveecrabchee and make abradedarea6 ?rone No abeorbinq moreslain Nhan surroundina areao.

Page 43: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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SANDING IN TIGHT SP()TS

r[ Iltl fiIl llll llll ijll ltl illr ill lllr rllt iltr inl lll ilI] illl lllt lll]

eurtace of a Viece of furni'Lure may noN be aVVarent, to ./, ,;Lhe Louch or under ordinaryl iqh t ,bu tbecome obv ioue tin a f lood of l ight.To checkyour work afLer eandinq a work-piece, clean off the eandinq VarLiclee(paqe 42), then aim a beamfrom af laehl ight aNIheeurface, bouncing i l otr Lhe wood aN an obl ique angle. gr iqhldirect eunl iqht worko equal ly wel l . Clooely examine Nhe eur-f ace, bobbinq your head up and down olowly Io benefiL fromevery anqle. Take nole of any flawo you miesed earlier.

Smoothing a raised panel's edgesSome sanding jobs cal l for a certaindegree of improvisation. For example,to smooth the beveled edges of araised panel (above) without roundingthe square edges of the frame, usea piece of sandpaper folded in thirdsto about the width of the beveledsect ion. Hold the paper in a U shapeand place one f inger behind i t ; thefolded paper cannot slip against yourfinger. Sand the edges, applying evenpressure and working paral lel to thewood grarn,

1HO?TI? N

Findingflawo .$o.

Oomebtemiehee onrhe \2"

Page 44: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

CLEANING SANDING PARTICLES

Removing sanding dust froma wood surfaceClean particles off wood surfaces afterevery stage of sanding before movingon to a f iner gr i t abrasive or applyinga f in ish . Remove as much dus t andgri t as possible with a vacuum cleaner,rag or bench brush (above, /eff). Thenwipe the sur face c lean w i th a tackclolh (above, nghf). Sweep your handacross the surface to check for anyremaining part ic les. Wipe again withthe tack cloth i f necessarv.

ilIl llu illI llr illl llr llr1 tlll fill lllt ltfl fiIl llll illt ltlj llll lltl lI]9HO7 Tt?Making ataak alothMake a tack cloth No match thetiniehinq producL you inhend t ouee. For a water-based finieh,oimVly damVen a clean Viece ofcheeeecloth wilh waten For ae o lv e n I -b ae e d f in ish , d amp entrhe cloth wiNh mineral spi i i ts,then workin a few drops of var-nioh.?queeze Ihe cloLh re?eat-edly unbil iN begino Io feel obicky.Add varnish when i t , loees i tsNacky feel. )tore a tack cloth ina plaelic bag with a label identi-tying it as eilher waNer- or sol-vent-based,

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Page 45: The Art of Woodworking - Wood Finishing

REPAIRING SURFACE DAMAGEIITIIIItIIIItIIIIIIIrIIIIIItItII

Tl laws on a wood surface can show.F through almost any finish. In fact, aclear finish like lacquer may magnifyimperfections. Before you apply a fin-ish to a piece of furniture, you need tofind and mend any surface damage.Most defects stick out, but you need tofind and eliminate the less obvious blem-ishes as well. Tiy running a hand acrossthe wood and feeling for them. You canalso wash the surface with low angle light(page 4) and look for them.

The best approach to a repair andthe materials required depend on thenature of the damage. A suitable repairfor a dent, for example, is to lift it withsteam (page 4).However, if the woodfibers are severed rather than simplycrushed, steam will not work; a woodfiller maybe the best remedy. For smallblemishes, wax or shellac stick can pro-duce a virtually invisible fix. Both areavailable in.a variety of colors to matchmany wooo specres.

You can buy special burn-in kitsfor applying shellac sticks. The typi-cal package includes a burn-in knifewith a gentlybent, stainless steel blade;an alcohol lamp for heating the knife;and a special solution for soaking a feltblock that levels the repair with the sur-rounding surface.

Most larger blemishes are best con-cealed with wood filler. Although many

W(l(lD PATCHING C(lMP(lUNDS

tfpes are pre-colored, you can tint filleryourself for a perfect match. Test thefiller on a scrap of the target woodbefore committing yourself to a par-ticular formulation. In situations wherea filler is inappropriate-because thedamaged area is too large or the fillerwould be conspicuous-you can mendthe defect with a shop-made patchfashioned from a wood scrap of thesame species (page 47).

Most modern patching compoundsare formulated to be chemically com-patible with a variety of finishes, but incases where the two products containthe same solvent, the finish can dissolvethe filler. Use the chart below to helpchoose the appropriate compound.

For all your fixes, whether lifting adent or filling a gouge, lightly sand therepair once you are done to level it withthe surrounding surface.

A traditional shellac stick remains one of the bestmethods of repairing minor damage in wood.Heated by the llame from an alcohol lamp, aburn-in knife melts a small bit of the shellacsticl<, which fills the hole level with the surface.

TYPE

Wood fi l ler

Wax stick

Shellac stick

Shop-made fi l ler

CHARACTERISTICS

Solvent- or water-based; dependingon type, can be tinted with stain orpurchased pre-tinted

Wax- and resin-based; available ina variety of colors. Sets quickly

Shellac- and resin-based; availablein a variety of colors. Sets quicklyto form a hard surface

Sawdust mixed with binder,such as hide glue or shellac; can betinted with stain

USES

Filling large holes, gouges,cracks and dents

Fil l ing small holes, scratchesand cracks

Fi lling scratches, dentsand gouges

Fil l ing nanow cracks,gaps and small holes

G(lMPATIBILITIES

Compatible with most f inishes;apply before or after stain

May be incompatible withlacquer; apply after f inishing

May be incompatible with alcohol- orlacquer-based finishes; apply beforeor after f inishing

Comoatible with most f inishes

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PREPARING THE SURFACE

LIFTING DENTS

Repairing a dented surfaceOne way to f ix a dent in wood is toswell crushed wood fibers to their orig-inal shaoe. Turn a household i ron toits highest setting and allow it to heatuo. Meanwhi le. soak a clean cloth inwater, fold i t over a few t imes andplace i t on the dent. Press the t ip ofthe iron against the cloth over the dent(above), holding i t in place unt i l thecloth steams. The steam will swell thewood f ibers, l i f t ing out the dent. Addwater to the cloth as necessary andavoid leaving the i ron on the cloth fortoo long, which may scorch the wood.

llll llll llll llll llll llll llll llll'fiI tl|l lll lllt flll lll] illl illt llll llt9HO7 Tt?Gluing an edge eplinter backA emall eplinter on the edqe of a work-Viece can be qlued in Vlace, ao lonq aoiN ie eLill afLached. Clamo trhe etrock in aviee and equeeze oome qlue into lhe qapbeiween Nhe eolinter and Lhe wood. ThenpreeeNhe epl inler into place and securei t wibh maekinq tape. )nce the qlue iodry, remove lhe IaVe and sand the repairflueh wilh adjacent eurtacee.

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Page 47: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

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FILLING SMALT NICKS AND NAIL HOLES

Melting shellac stick with a soldering gunSelect a shel lac st ick of the appropriate color and set a solder-ing gun on Low. Holding the st ick over the hole, melt i t wi ththe tip of the gun (above, lefil. Drip enough of the product tof i l l the ho le . Whi le the f i l l e r i s s t i l l so f t , use a kn i fe o r a woodchisel to press i t evenly into the damaged area. Work careful lyto avoid marr ing the surrounding area with the kni fe or chisel

Apply ing wood f i l lerChoose a f i l ler that is compat ib le wi ththe ingredients and color of the f in ishyou wi l l be apply ing, Use a put ty kni feto work the f i l ler in to the hole and over-f i l l i t sl ightly (left), then scrape off theexcess to level i t wi th the surroundingsurface. Avoid spreading fi l ler onto undam-aged areas, where it may cause unevenco lo r i ng i f a s ta in i s app l i ed .

b lade. A l low the f i l l e r to coo l . To leve l the f i l l e r w i th the sur -rounding surface, soak the bottom of a fel t block with a smal lamount o f commerc ia l leve l ing so lu t ion and l igh t ly rub theblock back and forth across the repau (above, nghf). The slow-act ing solvent in the solut ion dissolves excess f i l ler withoutharming the wood.

Page 48: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

Applying shellac stick witha burn-in knifeLight the alcohol torch and hold theburn-in knife over the wick for severalseconds. With the shel lac st ick overthe damaged area, press the kni feagainst the st ick so that enough f i l lermelts and drrps into the hole (above)Reheat the kni fe as necessary unt i lthe ho le i s f i l l ed . Use the kn i fe tospread the f i l l e r even ly . F in ish therepa i r w i th leve l ing so lu t ion and af p l i h l n n k ( n a o e 1 . 6 )

t P v b v ' v t

iiti ilt llr illl lll1 illr r]ll lrl llli illl rll} ll11 lll1 ilI] ilt rxl llll filt5HO7 Tt?Ueing a glue gun to applyshellac stickA qlue qun offero a oimple alternalivelo a burn- in kni fe or solderina aun forrepair inq damaqe with a ehel lacstick. Uee a oharp knife Nowhi l t le a ehel lac el ick oothat, iN fit 6 in Nhe barrel of "'your 4 lue 4un. Io me lL lhe - . ' .f i l ler, pul l Lhe Lr iqqer aeyouwou ldNo aVVly q lue , / .Ihen dr ip Lhe melLed ehel lac

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eNick onto Nhe damaqed area. Tress Nhe fil lerinbo Nhe hole wiLh a knife or wood chiee| andlevel iN as shown on ?aqe 45-uoinq a felNblock and level inq eolul ion.

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PREPARING THE SURFACE

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PATCHING A LARGER HOIE

1 Making and outlining the patchI An effective way to mend a largerhole on a wood surface is to cut a patchand a match ing mor t i se over the ho le ,then g lue the pa tch in p lace . Us ing acut-off scrap from the workpiece, or ap iece o f veneer w i th s imi la r g ra in andcolor, cut a patch that is s l ight ly largerthan the hole. Give the patch a diamondshape, less conspicuous than a squareor rectangular patch after the f in ish isappl ied. Use a wood chisel to bevel theedges of the bottom face of the patch,then sand both faces. Place the patchover the hole, al igning i ts grain with thesurface grain, and mark i ts out l ine witha sharp pencil (righil.

r) Chiseling the mortiseL Secure the workpiece with a clampif necessary. Select a wood chisel slightlynarrower than the sides of the mortise tocut along the out l ine. Ti l t the tool with i tsbevel facing up to produce an angle cor-responding to that on the edges of thepatch. Remove the remaining waste fromthe out l ine with the chisel bevel facingdown (left). Periodically test-fit the patchin the mort ise unt i l the mort ise is sl ight lyshal lower than the oatch is thick.

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PREPARING THE SURFACE

Q Gluing down the patchr-,1 Spread some glue in the mort iseand set the patch in place. Lay a pieceof wax paper over the patch, then posi-t ion a wood b lock on top . (The paperwi l l keep the pa tch f rom adher ing tothe block.) lf the patch is located whereyou cannot clamp it directly, set a boardatop the b lock and c lamp the ends tofocus the clamping pressure on the patch( lef t) . Work quickly to prevent thepatch f rom absorb ing mois tu re f romt h e g l u e a n d s w e l l i n g .

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PATCHING A DAMAGED CORNER' l Preparing the damaged areaI A damaged corner i s bes t repa i redwi th a pa tch . l f the edges o f the breakare ragged or sharp, use a wood chiselto cu t a sha l low, ova l -shaped mor t i sewi th smooth edges around the damage.Ho ld the ch ise l w i th the beve l fac ingdown and work w i th the s ra in o f thewood (right).

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Page 51: The Art of Woodworking - Wood Finishing

PRE,PARING THE SURFACE

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r) Installing the patchL Cuta patch that roughly fits themort ise, then shape i t with sandpaperor a chisel until it fits perfectly. Spreadsome g lue in the mor t i se and se tthe patch in posit ion, al igning i ts grainwith that of the workpiece. Use mask-ing tape to keep the pa tch in p lacewhi le the glue dr ies. To level the patchwith the surrounding surfaces, pareaway the excess with the chisel (above).Cut w i th the gra in , keep ing the ch ise lbevel s ide uo.

illr ult lltl |lt ll]l llt llll llll illt illl fiij tlll llil ljl] llt ljlj tjll ]jll1HO? TI?Filling adamaged aornerAn alternaliveNo patchin7 aaamaqed corneris lo reconslrucLit wilh wood fil ler.Secure Nhe workpiece \in a vise. Make a formNo keep Nhe fillerfrom l\ea4giiq by taVinq, 6ffl\lntn ?tece ol meLal or ,*./*-\

VlaeLic, or a tonque \ \'depreooor to thi side of the \ \

slock.lf you uoe a tonqe..de?reooor, place a etrip of wax Vapeiunderneath Lo keep Nhe f i l ler f rom bondinq to the st ick. Apply thefiller wiLh a ?uLIy knife, then LaVe a eecoid form Lo the ilp\r,fra"".

Page 52: The Art of Woodworking - Wood Finishing

RAISING THE GRAIN

Wetting the surfaceEvery phase of working with wood-fromjo in t ing and sawing boards to p lan ingand scraping them-compresses thefibers on the surface. Exoosure to watercauses the f ibers to stand up, roughen-ing the surface. l f you intend to use awater-based f inish, wet the surface toraise the grain before applying the f in-ishing solut ion. Spray water on the sur-face (left), then wipe off the excess witha clean cloth. Al low the surface to dry,then l ight ly scuff the wood with veryf ine (220-gr i I ) sandpaper. Avoid over-sanding, which might expose fresh grain,making it necessary to repeat the process.Raising the grain has other benefits, suchas lifting shallow dents, exposing defectsand he lp ing a f in ish adhere .

ilt illt i]l] lllt illt ult ilt] iltl uu ilu l]ll illJ ilu ]lil j-tl uu ull llt5HO? Tt?Coloring grain fillerUntrinted qrain liller canbe coloredf,o malch orconlrast with Ihe slainonYourworkoiece.For awaier-b aseA filler, use anoil-free piqmenL in liquid or ?ow-der form, such as universallinl-inq or dry earLh colors.TinL anoilbasedfiller wiNh an oil-basedpiqmenl, euch as arf,ieI's oil orjapan coloro,To prepare the fil ler,pour it.inho a dieh and add a emall amounN of the colorin7 aqent,Mlixthe Iwo inqredienle wibh a putty knife. Contrinue addinq color-inq aqenL unbil Nhe filler Nakee on the d,eeired color. Teet, the filleron a 6cra? board betore aVVlying illo your workViece. Add morecoloring aqenN No darken Nhe mixlure: add fil ler No liqhlen it.

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Page 53: The Art of Woodworking - Wood Finishing

FILLING THE GRAIN

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f , i l l ing the rvood grain is the easiestt rvay to achieve a high gloss, mirror-like finish on open-grained species likeash, oak and mahogany. Grain filler, alsoknorvn as pore filler or paste wood filler,is not arppropriate for every job, howev-er. A closed-srain wood has no needfor filler, and iome woodrvorkers avoidfillers altoeether in favor of a more nat-

t t It trat looK.

Ifyou decide to fil l the grain ofyourwood, you should understand the vari-ous options regarding ivhen to apply thefilier and exactly what type to use. Filleris usually applied before stain; if youchoose to stain before filling you mustbe careful not to damage the stain whenremovins the excess filler. Yet anotheralternatirie is to apply the stain and fillertogether on the rarv wood, although theresult is often a flat, monochromaticappearance. To bring out the characterof .t species like nrahogany, tly stainirrgthe wood, then sealing the stain with a

APPLYING A FILLER

wash coat (pnge 53), and finally apply-ing a fil ler with a conl.rasting color'.

Filler comes in sereral colors; choosea shade slightly deeper than the rvood

Applying n .filler to ttrt operr-grttittedspecies like onk does rtnre tlmrr

sitnply lill tlrc wood pores. ht corttrastwith the rnturtt l sttrface on the riglrt,

the Jiller added to the sartrpleon the leJi ltas accerrtrtsted tlrc

wood's grairr pntterrt.

so it willmatch as the ivood darkens r,vithage. You can also buy untinted filler andcolor it yourselfin the shop (pnge 50).Before committing yourself to a partic-ular sequence oL color, apply the fil lerto pieces of scrap wood both beforeand after staining, and choose the bestcon-lDlltaIlon.

For best results, make sure that theworkpiece is clean and dust-free. Thenprepire the fil ler following the manu-facturer's directions; it should have theconsistency of thick cream.

Because erain filler can absorb a lotof finish, ali,ays apply a wash coat to afilled surface before stainins or finish-ing i t . The wash coat, consi i t ing of thefinish you plan to r-rse diluted by theappropriate thinner, creates a barrierbetleen the fil ler and the finish. Withsorne species like mahogany, a wash coatis advisable before filling, to prevent thefiller from developing unsightly whitespots several months after it is applied.

1 Brushins on the f i l lerl -

I Wi th the workpiece face up on awork sur face, pour some of the f i l leri n to a con ta ine r . App l y t he f i l l e r w i t ha paintbrush ( le f t ) or abrasive pads.Us ing back -and - fo r th . ove r l app ingstrokes, cover the surface completelywr th t he f i l l e r , wo rk ing f i r s t w i t h t hegrain, then across it. Examine the work-n iece r rnde r d i rec t l i ph t t o con f i rmthat the surface is covered thoroughly.Apply more f i l ler , i f necessary.

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PREPARING THE SURFACE

Q Cleaning upr.J On a detailed workoiece such as araised panel, remove excess fil ler fromhard-to-reach spots with a sharpenedtongue depressor wrapped in a cleanpiece of burlap (lefl. Dab the pointedend into corners and along edges toremove excess f i l ler. Al low the f i l ler todry, then smooth the surface with 220-to 320-grit sandpaper. lf a second coatis required, apply i t the same way.

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O Wiping otf excess fil lerI Once the fil ler begins to dry, losingi ts shine and turning hazy, wipe i t witha piece of c lean burlap folded into apad tighil. Starting at one end of theworkpiece, work with a circular motionto pack the f i l ler into the wood poresand remove the excess.

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Page 55: The Art of Woodworking - Wood Finishing

PREPARING THE SURFACE

APPLYING A WASH C()AT

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1 Brushins on the wash coatt -

I Prepare a 50/50 solut ion of the f in-ish you intend to use, di luted with theappropr ia te th inner . Brush a long thewood grain to apply a l ight, even coatof the solut ion to the surface bbove),

r) Rubbing in the wash coatL tJse a clean. l int- free cloth towork the wash coat into the poresof the wood (lefil. Allow the washcoat to dry, then smooth the sur-face with extra f ine sandoaoer.

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Of course, not all wood cries outto be changed; some species are bestleft au natureL lt is hard to imagineimproving on the rich patterns ofrosewoo{ Macassar ebony or Grpa-thian elm burl, just as it seems futileto alter the shocking intensity of pur-pleheart, padauk or Osage orange.But for most woodworkers, oppor-tunities to work with perfect speci-mens are rare. The typical projectinvolves making do with whatevermaterials are available and afford-able. Stainshelp to makethis feasible.

Ebony-costly and difficult towor( but snikinglybeautifirl---offenaprime example ofthe special effecsthat staining makes possible. Even

A colonial red aniline dye stain enlivens a pale piece of oak.Whether it colors the wood fibers or merely covers the surfacewith a layer of pigments, staining can change the look of a work-piece more radically than any other step in the finishing process.

CFIANGNGTHE COLOR

rom the deep, clear andbrighttones of dye-tinted stains to the

dense richness of the pigment-tint-ed varieties, the materials used incoloring wood afford a great degreeof latitude. Sains allowyou to makewhite woods colorful,light woodsdar( plain woods fancy and steakedwoods uniform.

Throughout the long history offurnituremaking, stains have beencalled upon to fool the eye. Theyhave helped common woods takeon the appearance of more desir-able ones, adding color and figurewhere it was lacking. They have alsoproduced colors and patterns thatnature never imagined.

One trick involved inlaying mahogany surfaces with pat-terns of white holly. The challenge was to darken the sur-rounding wood without discoloring the inlay, and the solutionlay in a wash of potassium permanganate or dichromate. Thewash reacted with the high tannin content in the mahogany,bringing out rich reds and browns, but it left the tannin-freeholly unchanged.

Modern stains fall into two broad categories: those con-taining dyes and those with pigments. Dyes impart translu-cent color to wood, altering nature's palette while leaving theintricate grain patterns visible. Pigment stains contain opaquecolorants that cling to the surface of the wood. Pigments canbe used to add patterns and contrast to the wood grain, or tobring definition and highlights to corners and carvings.

Staining allows you to dramatically alter theoutward appearance of wood. This maple

piano bench was ebonized, or coloredblacl<"with multiple applications of tinted lacquer.

when the wood is available, the small tree diameter makes itimpossible to obtain wide boards and the natural instability ofthe wood virtually assures that a good-sized piece of ebonywill crack sooner or later. Fortunately, a widely used stainingtechnique called "ebonizing" gives the appearance ofebony tomore stable and affordable woods like mahogany and maple.

Perhaps more important than mere fakery is the ability ofstains to create new woods by adding unlikely colors to famil-iar materials. But not all staining is so blatantly obvious. Amore subtle, but equallyvaluable use of stain is to add to fur-niture that most elusive of traits: age. More than one "antique"

has come to market with adroitly applied mixtures of wax androttenstone, or even shop dust and japan colors, hiding thefact that the piece only recently left its makert hands.

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TOOLSAND ACCESSORIES

I long with an assortment of stains,A pigments and dyes, there are anumber of implements and accessoriesthat every finisher needs. A sampling ofthe most useful items is featured below.

Changing the color ofwood involvesas much art as science, but in someinstances precise measuring is helpful.For example, if you are attempting tomatch an earlier staining job, it helpsto know the exact proportions in whichthe original ingredients were mixed

together. Use graduated cylinders andcups to measure out liquids accurately,and a scale for determining preciseweights of powders, crystals and otherdry components.

Brushes, sponges, rags and pad appli-cators ofvarying sizes are the most com-mon tools for applying stains andbleaches. Brushes are categorized by thenature of their bristles. The brush youchoose for a particular project willdepend on the substances you need to

apply. Solvent-based stains should bespread on with natural-fiber brushes;use synthetic brushes to apply water-based products. An oil-based product,such as a pigmented wiping stain, canbe applied with either type of brush.

All ofthe products presented in thischapter are toxic to varying degrees.'v\hether mixing or applying a stain orbleach, wear safety goggles, neoprenerubber gloves and a dual-cartridgerespirator.

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AN II{VEI{TORY OF STAINING IMPTEMENTS

For applyinq stainoand bleachea. Synthetic bruaheamade from nylon or polyeeter are moredurable than naturaFbrbtb brushea

9pongeFor applyin4 bleacheaand chemicalstaina

f-----"1A 1

\ L=;---'\-==;'

Foam brushFor applyinq atainawithout bruah marka;type ohown ayntheticand diapoaable

Pad applicatorFor applyin4 atains even-ly on wide eurfacee; typeahown featureo rectan-4ular pad with thouaandaof ehorE filaments and afoam backinq

Graduated aylindereFor preciae meaoure-ment of liquid inqredi-ente in atains andbleachea

Glaee jarsClear jara uaed for mixingataine and bleachea;brown jare uaed foratorinq aolutions aincethey block out aomeof the li4ht

WeighingacaleFor preciaemeagurementof powdereand cryatalain ataina andbleachee

High-volume, low-preaaure (HVLP) apray unitFor aprayinq on etaine; featurea a turbine which blowaa oteady etream of air throu7h a epray qun, forcin7the atain through the 7un'a nozzle as a fine vapor

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BLEACHING

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T) leaches are hishlv reactive chemi-I) cals that brea'k down the naturalcolorants in wood. For years, wood-workers have used bleach to lishtenthe color oftheir stock. The effeit canbe startling. Mahogany tums a tone of palerose when bleached; walnut becomescreamy in color.

Bleaching has other applications,however, that go beyond simply wash-ing out color. The process can be thefirst step in preparing a piece for a spe-cific stain, such as a blond finish formahogany; it is also used to ready a darkoak for liming. In addition, bleaching isan effective way to suppress the colorvariations between the sanwood and

Natural cherrv

hearftvood ofa species like poplar andmake them more uniform. It also ridswood of water and rust stains.

There are three common types ofwood bleach. Oxalic acid. sold in licuidform as "deck brightener," is your bestchoice for removing stains from wood.Sodium hypochlorite will do an excel-lent job of removing an aniline dyestain from a workpiece. This product isavailable as liquid laundry bleach. Butthe most effective all-purpose woodlightener is two-part A/B wood bleach.Using this variety of bleach involvescombining lye and peroxide;the result-ing effect is stronger than that of eitherinqredient on its own.

Wood bleach can affect your tools asdrastically as the wood. Use a synthet-ic brush or sponge to apply bleach; anatural-bristle brush will eventually dis-integrate in the solution. Mix and storebleach in glass containers;the chemicalsmay react with metal. Bleaching leavesresidues on wood that can become haz-ardous airborne irritants when the sur-face is sanded. The three main tvoes ofbleach can all be washed away bf rins-ing the wood with water.

Bleach can be dangerous ifhandledimproperly, so follow the manufactur-er's instructions. Never mix bleach withanother chemical, and always workwith a fresh batch.

Nat.ural walnut

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Bleached cherry

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Dleached walnut

Page 60: The Art of Woodworking - Wood Finishing

CHANGING THE COLOR

BLEACHING WO()D

Applying the bleachClean the workp iece o f any d i r t o r o i l ,then ready the two-part bleach by pour-ing a quant i ty of each solut ion into sep-arate glass bowls. Do not mix the twopar ts together ; they w i l l be app l ied inseparate steps. Spread a generous buteven coat of Part A on the wood surfacewith a paintbrush or a rag. Let the prod-uct do its work for about 5 minutes, thenapply Pad B the same way. Let the work-piece si t for at least 4 hours, then r insethe surface with water or the neutral izersuppl ied with the bleach. Al low the work-piece to dry overnight before applying astain or f in ish. Two-part bleach is usual-ly strong enough so that one appl icat ionis suff ic ient; however, to l ighten thewood further, repeat the process.

ljll lll1 lllt illl llt fu r][ lllt ll11 tltl utl llt t]i} l]tl l]ll t]ll llit illl3HO7 Tt?Lightening wood wit"h 6rain fillerIo liqhLen wood wilhout bleachinqit , , use an oi l -baeed qrainf i l ler mixed wiNh somewhite pigmenN. FireI applya wash coaL to the work-piece (page 53),Lhen?re?are a balch offil ler (paqe 51),add inq enouqhwh i te j apan o r

- f / f ,

other o i l -basedoiamenls lo obla in T,he shadeyou wanl,.You can apply Ihe mixture ao you would anygrain f i l ler. Ihe Vroceoo wi l l accenluate Lhe grain ofo?en-?ore epecieo l ike oak, aeh, mahogany and elm.

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Page 61: The Art of Woodworking - Wood Finishing

THE VARIETIES OF WOOD STAINS

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Q taining was once key to the cabinet-l) maker's subtle art of forgery. fumedwith natural dyes, chemical mordantsand secret recipes, cabinetmakers couldimitate the look of prized, exotic woods,or give newly built chairs, chests andcabinets the patina that antiques acquirewith the passage of time.

Today, camouflaging and enhancingwood with stains are still importantaspects ofwoodworking. Whether a stainpenetrates and dyes the fibers ofthe wood,or merely covers the surface with a thinlayer ofpigments, no other step in the fin-ishing process brings about such a radi-cal change. Staining can highlight grainpatterns, mask homely surfaces, add col-or or impart a uniform hue to differentwoods within a single piece of furniture.

All stains consist of a coloring agentmixed in a liquid. The two basic types ofcoloring agents are dyes and pigments.Dye stains work much like the coloringagents used on cloth. Dissolved in water,oil or alcohol, they penetrate the surface

and bond to the wood fibers. Pigmentstains contain finely ground colored pow-ders suspended in a liquid such as linseedoil. They work more like very thin paints.When applied to wood, the liquid dries,binding the pigment to the surface.

Dyes for staining wood are most com-monly sold as aniline powders, whichmust be mixed with a liquid before use(page 68). Their intense colors can becombined in varying proportions to pro-vide a virtual rainbow of hues and tones.Pigment stains are available in the samewide range of colors, yet come in ready-to-use liquid, gel or glaze form. Pigmentscan also be purchased in concentratedform as earth pigments or japan colors;the concentrate is added to a ready-to-use stain for enhanced effects. Both dyesand pigments can be mixed with lac-quer, varnish, wax or shellac to providecolored finishes.

When choosing a stain, rememberthat most dye stains are brilliant andtransparent, but generally not as lightfast,

or impervious to fading, as pigmentstains. Dye stains are excellent for high-lighting grain. Pigment stains are opaqueand tend to cloud the grain. Some new-er liquid stains contain both dyes andpigments, providing the useful proper-ties of both qpes of coloring agents withadded ease of application.

The most desirable liquid base for astain depends on the effect you are seek-ing. The deeper the vehicle penetratesthe wood, the darker and richer theresulting color. Because water penetratesdeepest, water-soluble stains are gener-ally the best choice for hardwoods. Onedrawback of water, however, is that itraises the grain, necessitating furthersanding of the surface.

Available in easy-to-apply liquidform, the gel stain shown in use below

contains pigments that will impart adark brown mahogany tone.

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DYE STAINS

f-\ erived from plants, insects and ani-I-/ mals, the wood dyes used in the18th Century ranged from concoc-tions with exotic names such as drag-on's blood, verdigris, madder root andcochineal to more earthy tints extract-ed from tea, urine, vinegar and walnuthusks. A hundred years later, the firstaniline dye was extracted from coal tar.Today, such dyes are the industry stan-dard, usually mixed with one of threesolvents: watet oil or alcohol. Dyes not

yet combined with a solvent are alsoavailable in either powder or liquid form.Premixed stains are more convenient touse, but mixing them yourself gives youmore flexibility when you need to pro-duce a particular effect. A fourth typeof dye product, known as non-grain-raising (NGR) stain, is only available inliquid form. The dyes in NGR stains aredissolved in an anhydrous, or waterless,solution of organic hydrocarbons, suchas petroleum. Whichever type of dye

stainyou apply, the factor that will deter-mine the eventual color of the wood isthe amount of dye in the solution, notthe amount of solution applied.

Water*oluble sains are a good droicefor emphasizing the grain ofhardwoods.Although a water-based stain will raisethe grain, manywoodworkers prefer totake care ofthat step before applyingastan (page 50.), thereby saving a sand-ing step that might affect the final colorof the wood.

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Mahogany Mahogany

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CHANGING THE COLOR

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Alcohol-soluble dyes, also called"spirit stains," do not raise the grain asmuch as water-based stains and theyproduce somewhat brighter hues.

Oil-soluble dyes are transparent andalso non-grain-raising. The drying timesof these stains will vary, depending onthe solvent used. Mineral soirit-basedstains generally have a slow drying time,while stains containing toluene or xylenedry considerably faster. The trade-offisthat toluene and xylene are more toxic

than mineral spirits. Another potentialproblem with oil-based stains is theirtendenry to bleed through a protectivefinish. Although this should only occurif the stain is still wet when the topcoatis applied, it is a good practice nonethe-less to use a finish with a different solventthan your stain.

For best results, NGR stains shouldbe sprayed on wood. Ifyou use a brush,you will need to add a retarder to thesolution to extend its drying time.

Choosing the right stain for a projectcan involve experimentation. From pages60 to 63 is a series of photos that illus-trate the effects offive different dye stainson some of the most popular hardwoodspecies. The samples on the far left areunstained, followed by pieces cut fromthe same board, each one colored bya different dye stain. For further inforlmation on the characteristics and usesof stains, refer to the chart providedon page 70.

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CHANGING THE COLOR

CherryGolden fruitwood

- i:n.

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CherryNatural

Liqht yellow maple

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Page 65: The Art of Woodworking - Wood Finishing

OakEbony black

CHANGING THE COLOR

OakHone5fione amber

OakColonial dark red

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Page 66: The Art of Woodworking - Wood Finishing

PIGMENT STAINS

I ny substance that can be reducedl1' to a powder can become a pigmentthat will impart color to wood. Minerals,ores, metallic oxides and many othernaturally occurring earth compoundscan all be ground into very fine parti-cles. Once they are suspended in a sol-vent such as oil, varnish, pollmrethaneor water, these powders become spread-able pigment stains. Because the particlesare suspended, rather than dissolvedin the solution, pigment stains dry to a

thin, paint-like coating on the surfaceof the wood.

Whereas dye stains color wood fibersand tend to accentuate the grain, pig-ment stains are opaque and hide thewood patterns. As a result, pigmentstains are often used for glazing, grain-ing and other finishing techniques thatcompensate for the lack of distinct grainDatterns in certain varieties of wood.These are described in detail in Decora-tive Finishes (page 110).

Today, pigments are produced syn-thetically, with binders and driers addedto help them adhere to the wood as thesolvent dries. Pigment stains come indifferent liquid and gel forms. The mostpopular and best-known are pigment-ed wiping stains. These ready-to-use fin-ishing products contain a finely groundpigment suspended in linseed oil, whichdoubles as solvent and binding agent.Wping stains are slow-drying, allowingplenty of time to spread them on or wipe

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WalnutAntique white

wiping etain

WalnutCherry

wipinq atainMahoqany liqht

wipinq etain

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off any excess. Either sprayed on orapplied with a rag or a brush, they areparticularly useful when the wood sur-face is made uo of heartwood and con-trasting sapwood.

Other popular pigment stains includejapan colors, glazing stains and gel stains.lapan colors offer a more vibrant rangeof hues than wiping stains, but they needto be thinned before use. They can beused to tint other stains when you aretrying to match an existing surface.

The main selling point of glazingstains is that they are heavier and thick-er than wiping stains-and thus usefulfor concealing grain. Gel stains, mean-while, are easy to apply and they setquickly, reducing drips on vertical sur-faces. Refer to the chart on page 70 formore information on these and otherpigment stains.

Pigments are also available in pow-dered or concentrated form. Earth pig-ments, like siennas, umbers and ochres,

are mined from the earth and orocessedin deoxygenated conditions athigh heatto bring out their bright colors. Differentpigment stains can be mixed together orwith powdered or concentrated varietiesto produce unique colors and tones, pro-vided the solvents are compatiblel an oil-based stain cannot be mixed with awater-based stain, for example.

Pages 64 to 67 illustrate the effects ofvarious pigment stains on five differenttypes ofhardwoods.

MapleGolden oak

wipinq oLainMahoqany dark

wipinq etain

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EirahFlake whtLejapan color

Durnt umber4laztnq otatn

Kaw umberqlazing stain

Van Dyke brownglaztnq ot;ain

Page 69: The Art of Woodworking - Wood Finishing

CHANGING THE COLOR

EirahChrome yellow

japan color

EirahFermanent blue

japan color

EirchEuiletin redJaPan cotor

OakDyke brown

gel eLainvan Eurnt eienna

7el etain

Page 70: The Art of Woodworking - Wood Finishing

STAININGWOOD

applied and apparently uniform coatingof stain produces unevenresults on a piece of fur-niture. Unfortunately, dif-ferent parts of the sameboard cannot be expectedto absorb liquid evenly.Unless exposed end grainis sealed, for example, itwill usually take in more ,. "::.''t'': .. -':-'

o f a s t a i n t h a n f a c e s o r t , - . . , .edges, nraking the ends 1 .-appear darker. As shownon page 69, sealing endgrain is simply a matter of brushing on A test strip takes the guesswork outthe appropriate sealer before you stain. of staining. This sample illustrates

There are other preparations you the fficx on wtstained oak of one,should make at this stage. While a grain two and three coats of stain (ntovingf i l ler can be appl ied ei ther before or f i 'omleft tor ight) .Thebottomhalfafter staining, you need to raise the ofthe strip is topcoated to show howgrain of the wood (page 50) before the stain looks under a clear finish.

PREPARING A STAIN

oodworkers are quite naturallydisappointed when a carefully

applying a water-based stain. Otherwise,the stain will lift the wood fibers, requir-ing sanding that may remove the stain.

Many stains can be bought pre-mixed and ready to use. However,i f you enjoy experimenting, you may

also prefer to custommix your colors. Asshown in the photo atleft, a test strip can helpyou produce the rightcombination of ingre-dients and determinethe number of appl i -cations you will needto make.

From paintbrushesand rags to pad appli-cators and spray guns,

there are alternatives in applying stainsas well. \{hichever method you choose,wear safety goggles and rubber gloves.It is a good practice also to don a dual-cartridge respirator to filter out toxicf u m e s p r o d u c e d a s a s t a i n e v a p o -rales (page 19).

Mixing the ingredientsWhen working with dyes or pigmentsin powder form, use a wooden st ickto mix some of the powder with theappropriate solvent in a glass contain-er ( lef t) . Apply the stain to a samplestr ip of the wood that you wi l l be col-oring, Allow the strip to dry. To darkenthe co lo r o f the s ta in , add a smal lamount of powder to the solution. Tol ighten the stain, mix in a l i t t le moresolvent. Make another test strip, adjust-ing the color of the stain unt i l you aresat isf ied with the results.

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CHANGING THE COLOR

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READYING THE W()RKPIECE

Seal ing end gra inUse a rag o r pa in tb rush to app l y asealer to the end gra in of your work-p iece . Make ce r ta in t ha t t he p roduc tyou use for th is task is compat ib le wrththe s ta in and f i n i sh you w i l l be us ingSpread on she l l ac f o r wa te r - o r o i l -based s ta ins o r f i n i shes ; f o r a l coho l -based products, seal end gra in wi th anoi l -based wood condi t ioner . Avoid s lop-p ing the sealer onto the face or edge ofthe workpiece; th is cou ld af fect theeven ness of the sta i n .

llii r]ii llj lt ilji jlii iill lili ,ii,i tlj: ru u ru itji r*1Ho? TtP i,?reparing a nat'ural . * -un' ;"

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walnut, stain -,-.^,s"'t+r-\To make,,broue d,e noix,', z -.;[3*'-

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nalural walnuN dye eNain Vopularin the 1BOOz, collecL eeveral qreen /huaks f rom f a l len wa lnu la , le l l inq i .L h e m d r y a n d t u r n b l a c k . ) o a k | h e i ' ' -

huske for a few daye in a larqe non- i -_ ' -stick steel pot f i l led wilh waler,Then simmer Nhe mixNure for several ' " : ' ' - : -hours on a eLove, addinq one Iable- ! i . I ,eVoon of lye for every qal lon of the i . , , .mixture. SotrI le lhe solul ion in clear . ,glass lare and leave lhem in br iqhteunl io ,h l unl i l lhe mixf ,ure darkene fur-

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Nher . SL ra inLhe dyeLh rouqh an o ld c l o thand re-bot t le i t , d iecardinq Lhe hrske, Appl ied,wi lh a brush,"broue de notx" Vroducee a ranqeof r ich brown lones on wood.

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CHANGING THE COLOR

A GALLERY OF STAINS

TYPE

DYE STAINS

Water-basedstarn

Spir i t s ta in

0 i l s ta in

NGR sta in

Penetrating oilstain

Varnish stain

PIGMENT STAINS

Wiping sta in

Earth pigment

l a n a n n n l n r

Gel siain

Glazing stain

Water-basedstain

AVAILABLE FORM

Powdered ; water-sol uble

Powdered ; alcohol-sol uble

Powdered; oil-soluble

Liquid; d issolved inmethanol and petroleumdisti l late solution

Liquid; d issolved inmineral spirits

L iquid; d issolved invarn lsn

Liquid; suspended in o i land mineral spirits

Powder; soluble in anyl i qu i d

Liquid; concenirated invarn ish

Liquid; suspended inpetroleum-based gel

L iquid; suspended invarn ish

Liquid; suspended in anacrylic and water base

CHARACTERISTICS AND USES

Penetrating; not very l ightfast; transparent;bri l l iant; tends to raise grain; good for hard-woods; compatible with any finish

Penetrating; not l ightfast; dries quickly,but tends to leave lap and streak marks

Penetrating; transparent; does notobscure grain; slow-drying; bleeds; needssealer coat of shellac; good for softwoods

Does not raise grain; transparent andlightfast; good for veneers

Penetrates open-grained wood; moderatelylightfast; transparent; easy to apply; colorscan be mixed; does not raise or obscuregrain; bleeds; needs wash coat; good forsoftwoods

Highly transparent; lightfast; non-penetrating;adds fi l ler, color and gloss in one operation;good for lower grades of lumber

Lightfast; wil l not bleed; non-penetrating;opaque; tends to hide grain

Easy to use; l ightfast; opaque; hidesgrain; good for wood with indistinct grainor tinting protective finish

Excellent for t inting varnish, stain, lacquer

Easy to use; hides grain

Excellent for f iguring, shading, or conectingsap streaks; hides grain; wears off; needs ahard finish coat

Non-penetrating; l ightfast; bri l l iant; colorscan be mixed together; non-toxic andnon-f lammable

PREPARATION ANDAPPLICATION

Raise grain. Add to water, strain.Apply with brush, rag or spray gun.

Mix with alcohol and strain. Brushor wipe on. Best for small areas.

Dissolve in mineral or spirit petro-leum disti l late and sirain. Applywith nylon-bristle brush and wipeoff excess,

Thin to desired consistency.Apply with spray gun. lf applyingwith a brush or rag, use retarder.

Apply with brush or rag. Wipeoff excess after desired color isach ieved.

Apply with a rag and wipe off , oruse a spray gun.

Apply with brush, rag or spray gun.Wipe off excess after desired coloris achieved.

Mix wi th o i l or varn ish. Applywith brush, rag or spray gun.

Apply with synthetic brush.

Apply with rag; wipe off excessafter desired color is achieved.

Apply with brush or rag; allowto set. Wipe off with grain ifdesired.

Raise grain. Apply with brush,rag or spray gun.

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APPLYING A STAIN

lll1 rlll illt l|ll illl l| lllt ill fill tlll lll] llll lllt lll filt ilt ilIl filj?HO? TI?Controlling the flow of et ainAlLhouqh floodinq on stain ie Nhe recom-mended pracNice when working on a horizon-lal sur'face, doin4 the same when Nhe woodis verNical wi l l result in dr ippinq, and makea meoo of your projecL One answer ielo rig up a clean metal can lo regulatethe f low o f l iqu id f rom your b rush .Tunch Nwo holee on oppooite

Brushing on stainDip a clean paintbrush into the stain,coat ing about half the br ist le lengh.To minimize lap marks, flood the sur-face with stain and brush along thewood gra in in l igh t , even s t rokes(above). Once the surface is completelycovered, wipe it with a clean, dry, lint-free cloth to even out the color andsoak up excess l iqu id . For un i fo rmcoverage with an alcohol-based stain,wipe the surface as soon as possibleafter brushing i t on.

7i:;,": :,i: :3r::f;^in:"[;: M2?' [t:,"ni|il",xy ;:::(,* :wdraw the bristlee'acroee Nhe | -$::;y1ire, e,que,ezinq any exceoe \tr .l iquidbackintrolhe can. \. !$...

WooDSTAIN

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CHANGING THE COLOR

WooPSTAIN

Wiping on the stainFo ld a c lean, d ry , l in t - f ree c lo th in to apad and soak i t with stain, squeezing outthe excess unt i l the pad does not dr ip.Wipe the stain on the surface, workingparal lel to the grain ( /ef t) . Rub off theexcess with a clean cloth.

Using a pad applicatorF i l l the we l l o f a pad app l ica tortray half ful l of stain and pul l thepad over the rol ler, loading i t withthe l iqu id . Draw the app l ica tora long the workp iece fo l low ingthe grain (below), wetting the sur-face l iberal ly. Use a clean clothto wipe away the excess.

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llll lllr lll ull llu llrl lrJ lI] Illj lllj llll llll lltl lltI lll1 ljll i]ll lll9HO7 Tt?Gettin7 stain into tight, epoteKeep a selectr ion of smal l brusheson hand lo strain corner6, moldinqo,carvingo and lr im that a clotrh or

a laraer brush cannol reach. Forbrushes trhal are smal ler than

lhoee found in mosl hard-:. \ ware slores, try an art' . . .

\ ouVVly ohop.

Dipping a smal l workpieceTo color a workpiece that is toosmal l fo r b rush ing or w ip ing , d ip i tr ight into a container f i l led with thestain (abovd. Hold the piece overthe can to let the excess l iquid runoff , Then hold the piece by the cor-ners and w ipe i t w i th a c lean c lo th .

WooDSTAIN

- = / ' /

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Spraying a stainPrepare the spray gun fol lowing themanufacturer 's instruct ions. To staina piece of f urni ture l ike the one shownabove, ho ld the gun about 6 to 1Oinches from the surface with the nozzleperpendicular to the wood. Start ing atthe top of the piece, squeeze the tr iggerto apply the stain, moving the gun fromside to side in overlapping sweeps unt i lyou reach the bottom. For more infor-mat ion on ad lus t ing and us ing sprayequ ipment , re fe r to page 93 . Beforespray ing a s ta in , con tac t your loca lau thor i t ies to ensure tha t your sprayarea sat isf ies local safety regulat ions(page 102).

llll llll lll lll llll llfi lil lji lll lil i]lJ llll llll ilIl IIl illl illl llil1HO? TI?Supports for dryingAfEer st aininq a workpiece,let i t dry evenly andblemish-free on a beIn f a h n n - m a ) P G t t n -

n n r l a C t t l l n t t r 2 - i n r h -

equare wood blocks anddrive a smal l nai l Ihrouqhthe middle of each one.Arranqe trhe blocks on alevel surtace with the nailt iVe po in t inq uV so lha lthey wi l l eupporL the work-n i P a P e a : i l a r n r n c r a

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Page 77: The Art of Woodworking - Wood Finishing

PICKLINGAWOOD SURFACE

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ickling, or liming, refers to any oneof a number of antiquing tech-

niques intended to impart an aged andweathered look to lisht-colored wood.Traditionally, woodriorkers have pick-led furniture with such chemicals asnitric acid,lye and lime. As shown below,however, you can achieve comparableresults by applying a coat of white paint,pigmented white shellac or white glaze tothe workpiece. The trick is to wipe off

APPLYING A PICKLED FINISH

A pickled finish can give a newlymlde chair the time-worn

appearance of a vintage antique.

the bulk of the stain, leaving traces inmoldings and corners.

Once the pickled stain is dry it shouldbe sealed with a light topcoat. You canpickle either bare or stained wood sur-iaces, but ifyou have used a water-baseddye on the wood, you will also need toseal it prior to applying a latex paint orglaze. Pickling can be attempted withany species, but the process works bestwith oak or oine.

'l Applying the white stainI Use a rag to spread white paint or stain on the surfaces.Whi le the pa in t i s s t i l l wet , w ipe o f f the bu lk o f i t w i th aburlap rag, leaving a whitish glaze on flat surfaces and streaksof white in crevices and carvings (above). Let the stain dry.l f the e f fec t i s too pronounced, abrade the sur face w i th220-gr i t sandpaper unt i l you obtain the look you want.

11 "Aging" the surfaceZ to give the wood an ant ique appearance, use a rag torub a mixture of rottenstone and paste wax over the surface(abovd. Wipe off the excess with a burlap rag, taking care toleave some residue in the crevices and carvinqs.

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Page 78: The Art of Woodworking - Wood Finishing

CHEMICAL STAINS

p efore the advent ofsynthetic dyes,I) stainine wood was an art form ihatrivaled aljhemy. With natural dyesderived from plants and insects, andchemical mordants extracted from tin,i ron, aluminum and chrome, stainingrequired knowledge ofbotany and chem-istrv as well as exoerience with wood.

Applied by thimselves, natural dyesproduce pleasant shades of red andbrown on many species of wood. Tea,for example, is used occasionally on

antique reproductions to produce awarm golden hue. But in combinationwith chemical mordants, natural dyescan bring out a rainbow ofsuperb, bril-liant colors. The photos below and oppo-site illustrate the effects ofa few selecteddyes and mordants on four popularhardwoods. The species is indicated inbold tlpe with the dye or mordant list-ed directlybelow For more informationon a full range of mordants and natur-al dyes, refer to the chart on page 78.

The term mordant comes from theFrench verb mordre, meaning "to bite."Mordants do two things for naturaldyes:They change the color ofa dye througha chemical reaction with either the dye orthe wood. They also help a dye pene-trate wood and bind with the fibers.

Some natural dyes are available aspowdered extracts, but others must beextracted from natural oroducts in theshop. Mordants come in crystal, pow-der or liquid form. When preparing a

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ToLaaatum dichromateand tannic acid

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CherryDrazilwood and alum

AshLOqWOOA Logwood and

copper aulfate

F otaeei u m pe rm a n q a n atepaLaooium dichromaLe

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chemical stain, mix a 15 percent solu-tion of the dry ingredients and distilledwater. It is better to make the concen-tration too weak than too strong; it iseasier to darken the wood than to light-en it. Allow each coat to dry complete-ly before applying the next; color can bemisleading when the stain is wet.

Some natural dyes can cause allergicreactions, but most are relativelybenign.Many chemical mordants, however, arecaustic and sometimes toxic. Prepare and

apply these products carefully, wearingsafety goggles, neoprene gloves and arubber apron. A dual-cartridge respira-tor is a must for a mixture producingtoxic fumes. Do not spread a chemicalstain on bleached wood or you risk cre-ating poisonous chlorine gas. To avoidsplashes when diluting a mordant, addthe chemicalto thewater, a little at a time.

There are no hard and fast rules forapplyrng chemical stains. Typically, thedye solution is spread on the wood, then

the mordant is added while the dye isstill wet. The solutions should be mixedseparately and applied when cool.Experimentation is the key to goodresults; keep a record ofyour recipes andthe colors they produce.

Chemical staining is becoming adying art. Many products can be foundonly at photography and chemical sup-ply houses. But if you are after strikingand unique effects, they can be wellworth the trouble of seeking them out.

MahoganyLo7wood and

OakFotaaaium

Permanqanate

Mahogany9umac and

copper aulfate

Mahogany

potaaoium dichromate

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Loqwood and alum

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CHEMICAI MORDANTS AND NATURAL DYESI

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MORDANT

Alum

Ammonia

Copper sulfate(b lue v i t r io l )

Fenous sulfatefnnnnoras l

Hydrated l ime(quick l ime)

Potassium carbonate

Potassium dichromate

Potassiumpermanganare

Sodium hydroxide

Stannous chloride

Tannic ac id

I{ATURAL DYE

Alizarin

Alkanet root

Annato

Brazilwood

Coch ineal

Cutch

Dragon's blood

Fustic

lnd igo

Logwood

Madder root

FORM AND CHARACTERISTICS

White mineral salts; non-toxic

28% liquid solution; highly toxic

Blue copper crystals; highly toxic

lron crystals; highly toxic;reacts with tannin in wood

Calcium oxide crystals; toxic

Potash crystals; mildly toxic

Orange chrome crystals; extremely toxic;reacts to high tannin conient

Violet potash crystals; mildly toxic

White lye powder; toxic

White tin crystals; moderately toxic

Yellow powder extracted from hemlockand oak; mildly toxic

FORM AND ORIGIN

A synthetic dye or the active coloringagent of madder root

An ancient organic dye fromthe borage family

Seeds from a Central American tree

A popular dye from several species ofSouth American redwood trees

Dried tropical insects

An extract of the heartwood ofthe Asian acacia tree

A resin from the fruit of the rattan palm

An extract from the heartwood ofthe American mulbeny tree

A dye extracted from Indianindigo plants

An extract from Central Americancampeche hardwoods

Extracted from the roots ofthe Eurasian madder plant

COIORS PRODUCED

Purplish and dark crimson tones(For fuming) Dark violet browns with logwood dye; l ight yellowbrowns with brazilwood dye

(For preserving wood) Dark gray and olive tones withlogwood dye

Steel gray to bluish tones; ebony-like black with logwoodoye or alum

Antique limed finish on hardwoods such as cherryand walnut; must be neutralized with vinegar

A range of greens with alum and fustic

Deep reds to rich browns; combines well with anil ine dyes

(For ebonizing) Turns wood with high tannin content apurplish brown

Darkens cheny and oak; must be neutralized with vinegar

Light red with brazilwood dye; pink with alizarin; combineswell with many dyes

Boosts tannin content in wood

COLIIRS PRODUCED"Turkish red"; crimson, orange, yellow and brown,depending on the mordant(For French polishing) Gray tones with alum; a range of redswith l inseed oil

0ranges and golds with chrome, tin or alum; oak brownwith lye

Vibrant reds, browns, and purples, depending on the mordant

Many shades of red mixed with alum

Various lightfast shades of brown, from beige to chocolate

Bright, lightfast reds

Orange-yellow on its own; yellows to greenish-yellowswi th a lum

Deep blue; yellow-white with sodium hydroxide

Lightfast grays, browns, blacks, blues and purples, dependingon the mordant

Reds, blues, browns and yellows, depending on the mordant

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CHANGING THE COLOR

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APPLYING A CHEMICAL STAIN

Mixing the ingredientsIn prepar ing a natura l dye solut ion or achemical mordant , you wi l l general ly befo l l ow ing the d i rec t i ons supp l i ed w i ththe co lo r i ng agen t . Bu t i t i s impo r tan tt o h c v p r v n r p . i s p i n n n m h i n i n o t h p c p

ingredients. Measure out the dry ingre-d ien ts w i t h a sca le and se t t hem as idein a d i sh . l f you r rec ipe ca l l s f o r bo i l i ngn r h n t u r e i o r \ / n | a 2 n t r c ^ ^ r , ^ + | r ^ r ^v r r r u L v v u L U r . _ y v u u o r I U J C d n C L L I C L U

h e a t u p t h e l r q u i d . F i l l a m e a s u r i n gcup wi th the volume of water you need,i h p n n n r r r i t i n i n : o l z c . : ^ - A r r r L ^. . , , . , T - - ' b , - - ) l d r . n u u L | u

dry i ng red ien ts t o t he wa te r s l ow ly(ahnve ) s t i r r i np t hc sn lu t i on w i t h awood st ick unt i l the powder d issolves.App l y t he rn i x tu re t o you r wo rkp iecewi th a synthet ic sponge, fo l lowing theprocedure for wip ing on a sta in wi th acloth (page 72).

un t i l iN tu rne c loudy andqray: Lhie ehould Lakeaboul a week. Then ELrainlhe solut ion Nhrough ar^.off ee filt.er Tn nnnlv 1.16.- Y Y ' J "a l a i n a n n n n e a a r t e r a l

coals of iN on the wood,let r t inq each appl icat iondry before ?rtttnq onLhe nexN. Af|er thelael coaL, brush orsome l i qu id , ammon iaor flood Lhe sufiacewi th waLer to neuf , ra l -ize the ac id, in the v ine-qar . Then sand Nhe wood.

' ]l, iiii i:i, u, tili 'lJ lu ]]u iiu lll ,lii di ilii '.ili rill ijil illl5HO7 Tt?A chemical stain for ebonizingTo make your own sf,ain for lurning a wood black, oub-merqe a ef,eel wool pad and a few ruoty nai ls in a larqeqlaoo jar f i l led wibh c ider v inegar.LeI lhe mixttre sif,, uncovered,

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":,.!*fi.lrya:,1u

: . - : . . . - : . . . .

Page 82: The Art of Woodworking - Wood Finishing

FUMING

, . - , . r ' r l ' ^ . h ' , . ' . r . " j S t i C S O l - i . l 1 1 l 1 O -l r ! l r r L r r L \ r l ( l r ( r \ r \ r

{.,..-.r nia is its tendenq, to react lvith thetirnnin in lvood. Exposed to a piece offurniture, this rvater-soluble liquid rvilldarken the rvood, gir,ing it the classic bokof an antique. In oak and cherry, aumo-nia rvill bring oLrt a vatrietv of hues rang-ing from light hone,v to dark brorvtr.Depending on the an-u'rturt of exposure,the chenr ic . r l rv i l l t t r r r r :o t t t c spcc iesahrost black.

Nat,ural maho1any

Ammonia can be appl ied by ei thersponging or brushing the liqLrid or by suf-ftising the lr,ood in ammonia vapor insidea shop-built tent. This secoud option,called fuming, has definite adr,antages.The process colors exposed surf,lces e\.elt-ly rvithout lap marks or streaks. Andalthough the fhmes penetrate the ivoodmore deeply than brushed-on liquidammonia, fuming does not raise thegrain, since no liquid contacts the rvood.

NaLural walnuL

You cirn firme wood rvith regularhousehold aulrol l ia, but aqueousar.r.l.r-u'u-r irr, avai I able f r"om ch e nr i cal sr"r p -

ply hor-rses in ir 28 perceut scllution, lvorksrulrch r.nore quickl1,. Both products arecaustic and harmftrlto the eyes, skin irndrespilatory s,vstem; concentrtrted amtlo-nia ftrmes cau e\ren be fhtal if inhaled. Ifpossible, fi.rme rvood outdoors; rveirr rub-ber gloves, safety goggles arnd a dual-car-tridge respirator.

NaLural oak

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Fumed maho1any Fumed walnut Fumed oak

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EXPOSING FURNITURE TO AMM()NIA FUMES

Using a fuming tentBui ld a wood frame that is a l i t t le largerthan your workpiece. Use triangular brack-ets to reinforce the corners and a barclamp to hold the corners square as younail the frame together (above). Removeany metal hardware from your workpiecebefore p lac ing i t in the f rame; o ther -w ise , the ammonia w i l l ta rn ish the met -al . To complete the tent, drape a blackplast ic tarp over the frame. Use ducttape to seal any openings in the tarp andgather it tightly around the frame, leavingone f lap open. F i l l severa l d ishes w i thammonia and set the containers in the tent(right). Seal the f lap and let the fumeswork for about 24 hours, checking onthe workpiece periodical ly and toppingup the dishes with fresh ammonia. Removethe piece when i t has the color you want,keep ing in mind tha t i t w i l l darken a l i t -t le more after i t is exposed to the air .

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microscope, wood lools like a bundle ofstraws-wood absorbs finish at differ-ent rates. Applying a uniform coatingof a finish often results in what appearsto be uneven coverage. The reason isthat end grain absorbs more finish,leaving its surface looking bare, whilethe adjacent faces and edges appearadequately covered. The solution is toflood on a coat of finish and allow dif-ferent amounts to be taken in by theend and flat grain areas. The wood willthen be properly covered when youwipe offthe excess.

Over time, finishers must have grownimpatient with the thin coats that wip-ing produces, and brushes were intro-duced to the process. Brushes enable youto get into the most inaccessible of carv-

ings and crevices, to apply finish quickly in thicker coats and,not incidentally, to keep your hands clean. Today, with the var-ious bristle types and brush configurations available, there isa brush for virtually every variety of finishing product.

Application times were further reduced starting in the 1920swith the development of the spray gun. Spraying is by far thequickest way to apply a finish, blanketing the wood in a cloudof finely atomized fluid. But technology comes with its draw-backs. Spray guns can be wasteful, for a substantial portion ofthat cloud generally misses its mark. One of the goals of fin-ishing equipment designers is to create a new generation ofspray guns that preserve their traditional speed ofoperationwhile curbing wastefulness.

Spraying makes quick work of finishing intri-cate turnings. Quick-dryingfinishes like lac-quer and shellac are ideal for this technique.

PROTECTT\tr FINSHES

nlike a cabinetmaking project inwhich wood is cut away until you

are satisfied with the shape that remains,a finish is built up layer by layer. Simplyput, finishing is the process of spread-ing a fluid over wood to dry in thinsheets. And while it is a slower and lessdramatic stage of a project, ttre end resultis equally important in producing abeautiful piece of furniture.

Perhaps the most impressive aspectof a finish is the amount of protectionit will provide. Most commercial finish-es are no thicker than the page of a boo(yet they must guard the wood on whichthey rest from dirt, moisture and evenmild abrasion.

The earliest clear finishes were prob-ably applied in the simplest way-wipedon with whatever was at hand. A true oil finish consists ofnothing more than natural drying oils flooded onto the wood.The excess is then wiped off, leaving a thin film to dry. Oneor two coats seal the surface and subsequent layers can be builtup to almost any thickness or sheen. Even today, the term"hand-rubbed finish" conjures up an image of luster and qual-ity. Shellac, a naturally occurring resin, can be handled in muchthe same way as oil. One or two coats seal the wood, but youcan keep adding coats to develop the deep, glosy surhce knownas French polish (page 106).

Most topcoats can be applied by hand, and wiping ranksas one ofthe best and easiest ways to ensure thin, even cov-erage of a wood surface. Because of its structure-under a

A varnish topcoat brings out the lusterof an oak table. Finishing a piece by

hand demands care. Loading the brushwith too much finish, particularlywhen coating vertical surfaces, can

result in driDs and runs.

Page 86: The Art of Woodworking - Wood Finishing

TOOLS AND ACCESSORIE,S

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I, \ s i v i th r l l the o ther s tages o f al1 f in ishing project, the .rppl icat ionstage rvi l l be helped along by a fewspecialized accessories. Ifyou have thepat ience and energy to apply a l i t t leelbow grease, there are ir wide assort-ment of c loths, pads and brushes forcor,ering a surface. Cloths and pads canbe made and prepared in the shop fromold sheets or linen; you can also fash-ion your own foam brv,sh (pnge 92).Brushes come in different styles, sizesand price ranges. Should you opt forthe bristle over the foam variety, a high-qual i ty brLrsh is a good, long-terminvestment. I t wi l l out last a cheaperbrush, but, rnore important ly, i t wi l lalso produce a better finish.

There arre two pr incipal types ofspray systems on the market. Unt i llecently, the only system available fea-tured a col .npressor hooked up to aspray guu. Today, the more compacthigh-r,olurne, low-pressure (HVLP) sys-tem is becorring more prevalent. Withless overspray and hence less waste, theHVLP is more economical to operateand easier on the enr,ironment.

With both spray systems, you needto cor-rttrin the fumes and exhaust themsafeiy. The commercial spray bootl-rshorvn at r ight is a good al ternat ive,provided the workpiece is small enoughto fit inside the booth.

Commeraial spray boothFor eprayin4 amall work'p iecee. Made o f aheeLmera l . Featurea f i l te roLhat col lect overoprayand an exp loe ton-proo ffan and chimney LhatexhauaL fumee ouLeideLhe workehop

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High -vol u m e, Iow- p reea u reepray 6y6temFeaturee an electric turbinethat euppliee a qreat deal ofair at. low preggure to spray7un; ailowe hiqh percentaqe offtnieh to contacL workpiece

Vieaoeity cupHelpo in mixinq finteh Loproper coneteLency foreprayinq. Cup ie drppedrnto finteh and filled withliquid; Lhe time iL takeecup Lo empty throu1hhole in bottom ehouldcorreepond t.o elapoedLtme apecifted by manu-facturer

Foam brushAn rnexpenaive optton for applyinqfintehea withouL leavinq atreaka orotray briatleo on aurface; ideal forcontou red eurfacea and tiqht. 6pot6

Y-\----===i--Z---r.--=<-,Nat.ural or oynthet.ic

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brretlea for applying a ftniah:spreada a thicker, more evenc'oat than foam bruahConventional epray eyetem

Compreeoor ouppilee atream of pree'aurtzed air throu4h hoee to opray qun.Atr re7ulator controls volume and prea-aure of ar; requlator includee filter thatrernoveg mora|.ure and other tmpurittee

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?pray gun and cupCup aervee aa ftnish reser-voir; euction feeda finishLhrough metal tube to qun,where compressed air atom'izea the liquid into a mtetwhen tn4qer io pulled

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CHOOSING A PROTECTIVE FINISH

T h. protective finish you choose forI a project has a lot to do with your

personal taste and the effect you wish toachieve. The principal feature ofa prod-uct like tung oil, for example, is its capac-ity to penetrate wood, giving the surfacea warm glow and accentuating the grainand its pattern. A varnish or polyure-thane topcoat provides a higher degreeof protection by drying to a plasticJikefilm; however, itwill also maskthe sur-face details to some degree.

Many protective finishes, includingvarnish, polyurethane and lacquer, are

now available in two formulations: sol-vent- and water-based. Years ago, sol-vent-based products monopolized themarketplace, but recent environmentalconcerns have spurred the developmentof water-based finishes. Solvent-basedfinishes are generally flammable; water-based products are not. Another sell-ing point of water-based finishes is thatthey do not release toxic solvents intothe atmosphere except when they aresprayed, and thus complywith increas-ingly stringent air quality standards instates like California. The procedures for

preparing and applying a water-basedfinish maydifferfrom the methods usedfor is solvent-based counterpart. Alwaysrefer to the manufacturer's instructionsfor mixing and applying a topcoat.

Whichever finish you select, apply-ing it entails more than slopping on afew coas ofthe product and lettingthemdry. The wood surface has to be prop-erly prepared: Ifyou want to fill the grain(page 50) of an open-pore species likeoalg you will need to do so before apply-ing the finish. Before applyng a lacquertopcoat to an open-pore wood surface,a sealer coat may be in order. Finally,you will need to bleach or stain the pieceahead of time if changing its color (page54) ispartof your game plan.

Before preparing your tools andopening up your container of finish,make sure that any filler, wash coat orstain is completely dry. As a final prepa-ration, go over the wood surfaces witha tack cloth to be sure they are free ofsanding particles and dust.'

The procedures for applying a top-coat depend on the product you areusing and the application method youhave selected. Pages 87 to 90 detail thesteps for applying a wide range of prod-ucts by hand o5 where appropriate, withthe help of spray equipment.

Easy to apply, a coat of polymerizedtung oil is wiped onto the surface of thischerry toy chest, protecting the woodand giving it a warm luster.

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DRYING OILS

Drying oi ls, such as l inseed, tung and walnut oi l , are a groupof natural f in ishesthat cure to form a relat ively hard f i lm on awood surface. Tungoi l , also known as China wood oi l , is one ofthe most popular drying oi l f in ishes. Extracted from the nutof the tung tree, the oi l is avai lable in pure, modif ied and poly-merized form.

Because i t contains no addit ives, pure tung oi l is a goodchoice for f in ishing chi ldren's toys and eat ing utensi ls such assalad bowls. l f you are planning to use i t , check the label tomake sure that the contents are 100 percent pure. The mainbenef i t of modif ied tung oi ls is that they contain chemicaladd i t i ves tha t a l low them to d ry more qu ick ly . Po lymer izedtung oil undergoes a special heat treatment; it dries faster stil land produces a glossier sheen.

Drying oi ls are react ive f in ishes, meaning that they dry andharden when exoosed to air-even in a sealed container.When you store a drying oi l , use a containerthat is as smal las poss ib le to reduce the vo lume o f a i r to wh ich the o i l i sexposed. A couple of other suggestions are discussed in theShoo Tio below.

APPLICATION SEOUENCE

1. Wipe the oil on the surface with a cloth; it should beapplied straight from the container.

2. Let the oil soak into the wood (typically for 15 min-utes), then use a clean cloth to wipe off the excess.

3. Let the surface dry, usually overnight.

4. Sand the surface with 400-gr i t paper and removesanding part ic les.

5. Repeat steps 1 to 4 as many t imes as neces-sary to achieve the finish you want. Depending onthe wood, five coats of oil will typically yield a semi-gloss sheen.

6. Let the surface cure for at least a week before rub-bing out the finish (page 126).

llll llll lll llfl llll tll] fill fill illi lrit tjll illt llll fitl i]ll illt lllt illl9HO7 Tt??revent ing reaat ive finisheofrom drying out,Io expooe a reactive liniehIo ae l i I I le a i r as Vooo i -ble, pour iL intro a col lapei-ble VlaeLic conlainer l ikeNhoee ueed for pholo-graphic chemicale ( farr i7ht) , Col lapoe the foldsof Nhe conLainer to expela l l Nhe a i r , Ihen caV i tLi4htly (near riqht). lf youare keeoina a reactive finieh ina 7 laoo conLa ine r , d rop enouqhsmal l sLones or marblee inlo Nheliquid Io raise illo lhe level of thebrim,trhen ocrew onlhe caV,Whichever oloraqemethod you choooe, fix a label lo Nhe conNaineri dentifvin a lh e c o nlenNs.

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PROTECTIVE FINISHES

VARNISHVarnish is a highly durable protective coat-ing for wood, more resistant to heat andalcohol damage than products l ike shel lacand lacquer. Whether you are brushing i ton or using spray equipment, i t is also rel-atively easy to apply. lf you are brushing,try to work with a white wal l or a windowin back of the workpiece. The ref lectedl ight wi l l help you see i f you are skippingan area or i f you are picking up dust.

Varnishes were once made with naturalresins and oils like linseed oil. These materialshave since been supplanted by synthet icresins, but the old system of classi fy ingvarnish based on the orooortion of oil-to-resin st i l l prevai ls. Accordingly, varnishesare designated as either shoft, medium orlong oi l . Long-oi l varnish is slow drying,producing a soft and elast ic coat ing.Short-oi l varn ish is hard, and glossy-good for withstanding abrasion. Medium-o i l varn ish orov ides a f in ish tha t fa l l sbetween the two in gloss and durabi l i ty.

POTYURETHANE

Polyurethane is a transparent, varnish- l ike f in ish that isdurable, abrasion-resistant and easy to apply. Formulatedwith synthet ic resin, i t dr ies more quickly than varnish,making i t an ideal choice when you have l imited t ime forthe f in ishing work. Like varnish, polyurethane can bebrushed or sprayed on furni ture.

Polyurethanes are available in a variety of lusters, rang-ing from flat to glossy. Because they do not release toxicsolvents into the atmosphere while drying, water-based poly-urethanes are safer for the environment than their solvent-based counterparts. l f you plan to spray a water-basedpolyurethane, be sure your spray equipment is scrupulouslyclean; oi l wi l l contaminate the water-based product.

APPLICATI()N SEOUENCE (BRUSHING)

1. Di lute the varnish and spread a thin coat on the surface with a high-qual i ty br ist le brush; work f i rst against the grain, then with i t .

2. Let the surface dry, typically for 12 to 24 hours.

3. Sand the surface with a self-lubricating 240- or 280-griI sandpaper.

4. Repeat steps 1 to 3, using a stronger dilution of varnish and sanding thesurface with a f iner grit sandpaper (280- to 320-grit).

5. Brush on an undi luted coat of varnish.

6. Let the surface dry and sand with 400-grit sandpaper.

7. Repeat steps 5 and 6 two or three times.

8. Let the surface cure for 24to72 hours before rubbing out the f in ish.

APPLICATI(1N SESUENCE (SPRAYING)

1. Dilute the varnish to the proper viscosity (page 96)2. Set the spray gun at low pressure to minimize overspray and pooling.

3. Spray a thin coat on the surface.

4. Let the surface dry, then sand with 320-grit sandpaper.

5. Repeat steps 3 and 4 two or three times.

6. Let the surface cure for 24 Io 72 hours before rubbine out the finish.

APPLICATI()N SEOUENCE (BRUSHING)

l. Apply a thin and even coat with a paint brush or padappl icator, always brushing with the grain.

2. Let the surface dry for about 2 hours.

3. Sand the surface with a 320- to 400-grit sandpaper.

4. Repeat steps 1 to 3, abrading the surface with a finergr i t sandpaper.

5. Apply a f inal coat, giv ing the surface 18 to 24 hoursto dry before rubbing out the f in ish.

APPTICATION SEOUENCE (SPRAY]NG)

1. Spray the workpiece as you would for varnish, allowing30 to 60 minutes for the coat to dry.

2. Sand the surface with a 320- to 400-grit sandpaper.

3. Apply two more coats, using progressively finer gritsandpaper to abrade the surface after each application.

4. Wait at least 18 to 24 hours before rubbing outthe f in ish .

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SHELLACShel lac is a natural f in ish produced fromthe secretions of the lac insect, which isindigenous to Indochina and India. Thebugs feed on tree sap and expel a resinthat forms a protective shell around theirbodies. Eventual ly this mater ial bui lds upand is deposited on tree twigs and branch-es; it is then harvested and processed.

In i ts commercial forms, shel lac isavai lable both as a l iouid and in f lakes.Liquid shel lac is ready for use, but thef lakes must be mixed f i rst with dena-tured alcohol. In some regard, however,the flakes are the more convenient formof the product since you can prepare onlyas much of the solution as you need fora particular project. Both types of shel-lac are available in a variety of shades,ranging from dark brown and orange toblond and white.

Shel lac is also classi f ied accordingto its "pound cut," which refers to theamount of resin in the solvent. A 1-pound-cut shel lac, for instance, has one poundof resin for each gallon of solvent.

Shel lac comes in di f ferent grades,depending on where and when the prod-uct was harvested. Coarse shellac hasbits of twigs and bugs; the super-refinedvariety is vir tual ly pure l iquid.

Whi le shel lac provides a durable f in-ish that protects wood from humidityand abrasion, i t does not stand up wel lto water, alcohol or heat. Like other sol-vent-release finishes, shellac forms amilky cloud on a surface-cal led blush-ing- i f i t is sprayed in high humidi ty orwith excessive moisture in the solvent.Keep the solvent in a sealed container.

APPLICATION SEOUENCE (BRUSHING)

1. Either buy or prepare a 1- or 2-pound-cut shellac with which to apply twoor three wash coats to the surface (page 53i. Brush the finish on quicklyand evenly with as few strokes as possible, working with the grain only.Avoid overlapping the brushstrokes.

2. Let the surface dry, typically for at least 2 hours.

3. Sand the surface with a self-lubricating 360- or 400-grit sandpaper. Removesanding particles.

4. Brush on another coat, using a 3-pound-cut shel lac, then sand.

5. Apply three or more coats with a 5-pound-cut shellac, sanding before eachappl icat ion.

6. Al low 24 to 72 hours of drying t ime before rubbing out the f in ish.

APPTICATION SESUENCE (SPRAYII{G)

1. Prepare a solution with the proper consistency for spraying following themanufacturer 's instruct ions; a 1- or 2-pound-cut shel lac is typical . l f yo-are using l iquid shel lac, you may have to di lute i t .

2. Adjust the spray gun for a l ight coat to keep dr ips and runs to a minimum.

3. Spray on two or three wash coats.

4. Let the surface dry for about 30 minutes, then sand it wiih a self-lubricating 360- or 400-grit sandpaper. Remove sanding particles.

5. Spray on three or four additional coats using a more concentrated solutionand sanding between appl icat ions.

6. Let the finish dry for 48 to 72 hours before rubbing out.

A viscosity cup is used to test the consistencyof a finish for spraying. Proper dilution of

the finish will ensure that it coats a workpieceuniformly and with a minimum of dripping.

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PROTECTIVE FINISHES

LACOUER

APPTICATION SEOUENCE (BRUSHING)

1. Di lute the sanding sealer according to the manufacturer 's instruct ions andapply it to the workpiece. Let dry and sand with 320-grit paper.

2. Dilute the lacquer with a retarding solvent as specified by the manufacturer.(The retarder keeps the lacquer from hardening too quickly.)

3. Coat the workpiece with the finish using a soft, long-bristled brush. Workal a 45 angle to the surface and brush with the grain. Do not overlapbrushstrokes.

4. Let the lacquer dry (typically 2 hours), then sand with a self-lubrrcating360- to 400-grit sandpaper. Remove sanding particles.

5. Repeat steps 2 to 4, using a slightly more concentrated lacquer solution.

6. Apply at least two orthree additional coats. Avoid brushing undilutedlacquer on the surface; you should add at least a small amount of reiarderto the lacouer.

7. Let the finish dry for at least 24 hours before rubbing it out.

APPLICATI(lN SEOUENCE (SPRAYING)

1. Di lute the sanding sealer according to the manufacturer 's instruct ions andapply it to the workpiece. Let dry and sand with 32O-grit paper.

2. Prepare a diluted lacquer solution with the solvent recommended by themanufacturer and spray it onto the surface. Make sure the lacquer has theproper consistency for spraying; use a viscosity cup (page 90.

3. Let the finish dry for about an hour.

4. Sand with a self-lubricating 320-grit paper.

5. Repeat steps 2 and 3, sanding the surface l ight ly. (This step is opt ional.)

6. Spray on at least 3 more coats, di lut ing each appl icat ion with only a smal lamount of retarder and sanding the surface with a 360-grit paper.

7. Let the f inish dry completely before rubbing out.

Lacquer has been used as a protectivefinish for wood furniture in the Far Eastfor more than 2000 years, but it did notbecome oooular in the West unt i l the17th Century. The f i rst lacquers useddur ing Ch ina 's Chou dynas ty werederived from natural resins; today'sproducts are formulated synthet ical ly.

Lacquer can be brushed onto a sur-face, but be sure to use a brush withbristles set in rubber, otherwise the sol-vent in the f in ish may cause the tool toshed. The rapid drying t ime of lacqueralso makes i t wel l -sui ted for spraying.A lacquer topcoat hardens to a clearand durab le f in ish . l t i s a good cho icefor furni ture that may be exposed towater or high heat.

Unl ike polyurethanes and varnishes,which form separate layers with eachnew coat ing , each app l ica t ion o f lac -quer dissolves the previous coats tocrea te a s ing le f i lm. F in ishers usua l lytry to l imit themselves to four coatsof lacquer. But these are general ly inaddit ion to one or two coats of sandingsea ler . The th icker a lacquer f in ish isbui l t up, the greater the r isk of crack-ing . However , ob ta in ing a mi r ro r - l i kelacouer f in ish on soecies l ike rosewoodor oak may sometimes involve as manyas 10 aool icat ions. Finishers in ancientChina were known to apply more than300 coats on a s ing le p iece o f f u rn i -ture. To prevent cracking, they wouldcareful ly abrade the surface after eachnew app l ica t ion had dr ied and theykept each coat as thin as possible.

Lacquer is avai lable in a range ofsheens from f lat to glossy. There are dif-ferent tints to choose from as well, anda clear formulat ion that heightens thegrain and color without al ter ing the hue.

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Page 93: The Art of Woodworking - Wood Finishing

FINISHING BYHAND

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r"fi- here are essentially three methods3- of applying protective finishes by

hand: wiping the finishing material onwith a cloth or sponge, padding it on orusing a brush. The method you chooseshould depend on the type offinish youare applying. Wiping, for example, is thebest way to apply a drying oil. Varnish,polyuretl-rane, shellac and lacquer arebetter applied with a brush.

Sorne f inishing products, cal ledpadding finishes, are made to be paddedonto a surface; they provide somethingapproaching the luster of French pol-ished or laccuered wood with consider-ably less effort. However, because thesefinishes do not readily build up into athick coating, they stil l require a fairamount of time and work to apply. Asa result, they are most often used totouch up damaged finishes. As finishesfor newly built ftrrniture, they are bestsuited to ornamental details, turningsor small uieces like the table shownbelow Toreduce the amount of timerequired to build up a padding finish,first apply a sealer coat ofvarnish, shel-lac or laccuer.

WIPING ()R PADDING ON A FINISH

Using a cloth or spongeWet a c l ean c lo th o r a sponge w i th t he f i n i sh and w ipe a t h i n coa t o f t he l i qu idonto the surface (above). Make sure you cover the wood surfaces completely. Letthe f in ish soak in to the wood for several minutes, then use another c lean c loth towipe away the excess. Check the manufacturer 's inst ruct ions for dry ing t imes,then apply subsequent coats the same way.

Working with a padUse a p iece of l inen and some wool tomake a f i n i sh ing pad as you wou ld f o rFrench polishing (page 106). Pour a l iI-t l e o f t he f i n i sh on the pad . t hen tap i taga ins t t he pa lm o f you r hand to ge tthe pad un i f o rm ly damp. W ipe the padalong the sur face fo l lowing the d i rect ionof the grain (left). Overlap your strokesunt i l you have covered the ent i re work-n i p e p a n d t h o c r r r f : e o h ^ ^ ^ ^ - ^ ^ + hV , v u u u ' , v ' u u u r r o ) d ) l l l u u t l l ,

g lossy sheen. Consu l t the manufac tur -er 's instruct ions for drying t imes, thenapp ly subsequent coats . Padd ing f in -ishes usual ly require several appl icat ions.

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PROTECTIVE FINISHES

Brushing on a finishSet the workp iece s l igh t ly above yourwork surface so you can cover the woodr igh t to the bo t tom wi thout s lopp ingf in ish on the tab le . For a shop-madestand, prop the corners on wood blockswith smal l nai ls dr iven through them. l fyou are using a br ist le brush, dip aboutone- th i rd o f the br is t le length in thef in ish and brush a long the gra in leav ingbeh ind th in , even coats . Res is t thetemptat ion to spread the f in ish thicklyo r t h e l i q u i d w i l l r u n , s a g o r p o o l . T oavoid air bubbles and lap marks on thesurface, use as few brushstrokes as pos-s ib le . Use tweezers to remove s t raybrist les from the f in ish before i t has achance to d ry . A foam brush w i l l cu tdown on the problem of lap marks.

llll l]ll lllt lllJ illj llll llll llll llll llll llll llll rlll illt lll llrl llll llll1HO? TI?Afoam brushYou can make yourown d ieVoeab lefoam brushes tosuit any job at,hand. Uee ecrapwood for Nhe handleand a Viece of polyure'Ihane foam for lhe aoolicalor.You can buy polyurethane foam atfabr ic and upho lo te ry ohopo. Cut thefoam to Nhe eize you need,lhen told if, over oneend o f Lhe hand le and s lao le iN in o lace . Ueeeciseors to Nrim Lhe foam to the r iahl orof i lefor your workpiece.

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Page 95: The Art of Woodworking - Wood Finishing

SETTING UP YOUR SPRAY EQTJIPMENT

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ith a bit of practice, spraying isa highly efficient method of

applying professional-looking fi nishes.High-volume, low-pressure (HVLP)systems offer the best transfer efficien-cy-that is, they land a high percent-age ofthe spray on the workpiece andwaste less as overspray. Since they uselow-pressure air to create a mist of fin-ish, HVLP systems also create less"bounce back" than conventional sys-tems. Bounce back often occurs whenspraying is done in an enclosed space:The overspray rebounds toward thespray gun ind'settles on other surfaces.

The key to successful spraying is tokeep your equipment properly adjust-ed. With both HVLP and conventionalsystems the adjustments are made withthe actual solution you will be using, soyou will need to start the process bypreparing a batch of finish (page 96).

AI{ATOMY OF AI{ HVIP SPRAY SYSTEM

Spray gun and aupFiniah flowa from cup toqun where air turno liq-uid into a miet, direct-in4 it at the workpiece;cup unacrewa from 7un

Air hoseConnecta epray qun toturbine; atoree in turbinewhen not in uae

TurbineFeaturea a 7-amp motorthat powera a fan die-charqin4 [ow- preaeu re airthrou4h the air hoae; Lur-bine ia liqhtwei7ht andcompact compared tothe compreaaora usedon conventional ayatemo

ANATOMY OF A CONVENTIONAL SPRAY SYSTEM

To compreeaor

z--'-

Air preaeure gauge

Air re1ulator)eta volumeof air pumpedto gun

Fluid cup and lidaaaemblyFluid cup holda finish:uoually one quart orleao; acrewe on toepray qun in front oftrigqer. Compreaeed airatreaming throu4h guncreatea a vacuum thateiphono finiahfrom cupupto 1un. Lid aeaemblyclampeto cup

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ffi5pray gunAtomizea finieh into a opray; fea-turee fluid adjuetment acrew foroetting flow volume and apreaderadjuotment valve for regulatinqepray patrtern

HoeeHiqh-preaaure air fromcomPre69or, otroraqetank and air re4ulatorpaeeee throu4h hoeeto epray qun

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PROTECTIVE FINISHES

ADJUSTING AN HVLP SYSTEM

1 Adjusting the spray patternI Fi l l the cuo with f in ish and screw i tto the spray gun. For the model shown,turn the system on at the turbine, thenadjust the air cap to produce either a ver-t ical , hor izontal or c ircular spray pattern.As a rule of thumb, use the vertical set-ting to spray tops and other horizontalsurfaces, and the horizontal setting tospray vert ical surfaces. The circular pat-tern is wider than the other two and canbe used on any type of surface. Test allthree patterns on scrap wood before turn-ing your attention to the workpiece.

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r) Adjusting the flowL to set the volume of f in ish to besprayed from the gun, turn the f lowadjustment knob. Holding the gun noz-zle about 8 inches from a test surface,pull the trigger to start the spray. Thefinish should cover the surface evenlywithout dripping or pooling. lf the coat-ing is too thin, increase the flow by turn-ing the knob counterclockwise; i f thef inish drips or pools, decrease the f lowby turning the knob in the oppositedirection. To change the size of the spraypattern, either increase or decrease thedistance between the gun and the sur-face. This may throw off the flow adjust-ment, however. Moving the gun closerto the surface may require a decreasein the f low; simi lar ly, as you draw thegun away you may have to increasethe f low.

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ADIUSTING A CONVENTIONAT SPRAY SYSTEM

' l Setting the air pressureI Attach the air I ine from the compressor to the air in let onthe regulator. Then instal l the hose, connect ing one end to thea i r ou t le t on the regu la to r and the o ther to the a i r in le t onthe gun. To adjust the air pressure on the model shown, take

the f lu id cup off the spray gun and turn on the compressor,al lowing the tank to pressurize. Open the out let valve on thepressure gauge to the level specif ied by the manufacturer(above), typically about 50 psi,

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PROTECTIVE FINISHES

r) Adjusting the spray pattern and flowL r , l t h e f l u i d c u p w i t h f i n i s h a n dattach it to the spray gun. Adjust the spraypattern and the f low of the f in ish in thesame way tha t you wou ld fo r an HVLPsystem (page 94). Turn the fluid adjust-ment screw counterclockwise to increasethe f low and c lockwise to decrease i t .Use the spreader adjustment valve to setthe size of the spray pattern (right), turn-ing it counterclockwise to produce a larg-er pattern and in the opposite direct ionto narrow the scope of the spray.

PREPARING A FINISH

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Adjusting the consistency of a finishA f in ish may need to be th inned to theproper consistency before it can be sprayed.To determine the consistency of a f in ish-ing produc t , d ip a v iscos i ty cup in to thef luid, then l i f t i t out and t ime how long i ttakes for the cup to empty (left). lf thetime exceeds the interval specif ied by themanufac turer , d i lu te the f in ish w i th theappropriate solvent. Test the solut ion asmany t imes as necessary, but make surethat you get i t to the proper consistency.Before f i l l ing the f lu id cup, strain the f in-ish through a paint filter to remove impuri-t ies that might otherwise clog the spraysystem or mar the f in ish.

9 p reader adju eLment va lve

Flutdadjuetment6CTEW

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SOLVENT

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WORKING WITH SPRAY EQUIPMENT

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D oth your own safery and that of yourD neighbors should be a major con-cern associated with spraying a finish.Do not fail to put on the appropriategear for the task: safety goggles, rubbergloves, a rubber apron and a dual-car-tridge respirator. If you can smell thefinishing product through your respira-tor, it is not doing a good enough job.Adjust the device to fit properly on yourface, change the filters or replace the res-pirator. Refer to the chapter on safety(pnge 12)for more information on pro-tecting yourself.

Whether you are using water- or sol-vent-based products, you must set upyour spray area and exhaust the fumesyou generate in a manner that complies

SPRAYING A FINISH

The ideal distance betweert a spraygun nozzle and the stu'face to be

sprayed is about B inches. You cnrrLLse your outstretched fingers to

quickly gnuge the distance.

with federal, state and municipalrequire-ments. Pages 102 and 103 show a typicalspray room with some of the elementsthat may be necessary. However, it isessent ial to check your local regula-tions before outfitting your spray room.

\Ahile you are actually spraying, holdyour arm straight out in front ofvourbody. Whenever possible, keep the gunas nearly perpendicular to the wood sur-face as you can. As illustrated in the dia-gram below, a surface is covered with aseries of back-and-forth strokes thatoverlap each other and the edges ofthewood. Before actually spraying the fin-ish on a piece offtrrniture, practice a lit-tle on some cardboard or scrao wooduntil you have refined your technique.

Applying a full and even coatThe d iagram at le f t i l lust rates a sprayingsequence for apply ing c lear f in ishes. Thekey is to s tar t a t one corner and make aser ies of s t ra ight , over lapping passes thatwend the i r way to t he oppos i t e co rne r .Th rs f i r s t se r i es shou ld run ac ross t heg ra in o f t he wood . Then make ano the rseries of passes, this time working parallelto the grain. As you work, release the trig-ger each time you pass off the edge of thewood. To ensure an even coat , hold thegun pe rpend i cu la r t o t he su r face andkeep i t mov ing a t a l l t imes .

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PROTECTIVE FINISHES

A SPRAY ROOM DOTLYTo wheel a workpiece in and out ofyour spray room, and to move i taround without having to set handson the dry ing wood, use the shop-bui l t dol ly shown at r ight and below,The d imens ions in the i l l us t ra t ionwi l l y ield a dol ly that is large enoughfor most furniture projects.

Cut a p iece o f %- inch p lywoodfor the base, then screw the cornerblocks in place. Screw a caster ontoeach corner block. To set up thedo l ly fo r the p iece to be sprayed,dr ive na i l s th rough the centersof four wood blocks. Position theblocks on the base with the nail tios

point ing up so they wi l l support thecorners of the workpiece.

To use the do l l y , se t the p ieceon the nai ls. To avoid touching the

workpiece after spraying it, use yourfoot to move the dol ly. You can alsoattach a tow rope to the base anduse i t to pul l the dol ly along.

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PROTECTIVE FINISHES

tIIIIIIIIIIIItI

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Spraying the flat surfacesTo f inish a piece of furni ture, start with the outside surfaces,f i rst spraying the top and then the sides. In preparat ion forthe job, set the piece sl ight ly above your work surface, prop-p ing i t up on wood b locks w i th na i l s d r iven th rough them asshown overleaf. For the top, be sure to adjust the air cap tothe vertical spray pattern positron (page 94) and use a spraypattern that works f i rst across the grain and then with i t .Holding the gun at a sl ight angle to the surface, start at the

edge closest to you and work toward the opposite edge (abo-ve, lef t) . For the sides, set the air cap to the horizontalspray pattern posit ion and work with the gun perpendicularto the surface (above, right). To ensure even coverage, holdyour arm out straight to maintain a uniform distance betweenthe gun and the wood. Always work in straight l ines; c ircularspraying patterns wi l l leave the edges with a thinner coat ingthan the center.

Spraying the inside surfacesTo cover the ins ide o f a p iece o f f u rn i -tu re , s ta r t w i th the leas t consp icuoussur face . For the cab ine t shown, f i rs tspray the unders ide o f the top , beg in -n ing a t the back and mov ing towardthe open ing a t the f ron t . Be care fu lnot to aim the spray at yourself . Spraythe corners , the s ides . the back andf ina l l y the bo t tom o f the cab ine t ,

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PROTECTIVE FINISHES

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A TURNTABTE FOR SPRAYINGTo spray all the surfaces of a piece off u rn i tu re w i thout hav ing to moveyour equipment, use the shop-madeturntable shown at right. The deviceconsists of two pieces of plywoodwi th a "Lazy Susan" bear ing fas-tened in between. The setup allowsa piece of furniture to be rotated atany speed as i t is being sprayed.

To make the turntable, cut twopieces of 3/q-inch plywood slightlylarger than the width of the pieceof furni ture to be f in ished. Set thebase on a work surface and centerthe bearing on top of it. On the base,mark the access hole and the fourscrew holes in the inner r ing of thebearing. Bore the access hole throughthe base and dr i l l four pi lot holes,then aitach the bearing to the basewith screws. To fasten the turntablepiece, set the base on top of i t wi ththe bearing sandwiched betweenthe two pieces of wood. Aligning theedges of the pieces, s lowly rotatethe base unt i l the access hole in i tl ines up with one of the four screwholes in the outer ring of the bearing.Screw the bearing to the turntablepiece and repeat the process at theother three holes.

To use the tu rn tab le , cu t foursmal l wood b locks and dr ive na i l sthrough them. Set the workpiece onthe t ips o f the na i l s , then s lowlyrotate the turntable with one handwhi le opera t ing the spray gun w i ththe other (right, bottom).

Deartn4 acceaa hole Turntable ptece

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PROTECTIVE FINISHES

IIIIIIIIIIIIIIIIIIIIIIIIIIrtIIIr

Spraying contoured surfacesWhen spraying, treat contoured surfaces,such as chair spindles and legs, as i f theywere four-sided objects. Holding the gunat a sl ight angle to the wood, spray eachs ide in tu rn .

CLEANING THE SPRAY EOUIPMENTCleaning the spray gun and fluid cupTo keep your spray equipment in goodwork ing order , c lean the gun and f lu idcup after each use. For the HVLP systemshown, unscrew the cup f rom the gunand pour any f in ish lef t in the cup into aconta iner fo r s to rage or d isposa l . Thenpour a smal l amount of the appropriatesolvent into the cup and reattach it to thegun. Spray the solvent into an empty can.Repeat as many times as necessary untilthe solvent comes out clean. Wioe theouts ide o f the cup and gun, then pu l lthe suct ion tube assembly from the gun.Remove the a i r cap by unscrewing i t sretaining r ing from the gun; soak the twopieces br ief ly in solvent. Clean the f lu idnozzle, suct ion tube assembly and air capwith a soft brush dampened with solvent(/efil. Reassemble the gun and screw thef lu id cuo to i t .

Fluid nozzle

9uctiontubeaeaembly

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ANATOMY OF A SPRAY ROOM

IItI

Air filtereKemove haza rdouo parLicleefrom air: made of non-com-buattbte maLertal. At leaat.four 20" x 20" filLera arrayededge-Lo-edge requtred to pro-vide adequaLe pratecLian;need to be cleaned andreplaced re4ularly

Tube-axial fanExhauaLa atr from room Lo theoutdoora; rnounted on exteriarwa ll. F eatu rea expl aoi on - p roofmotor and epark-reeieLant pro-peller; available from induatrialouppliero. Moveo larqe volumeeof air efficiently uoing a mtnimala h ^ t r n t n f p l p r r r i r i + r '

Automaticaprinkler eystemWater eprinklereacttvated by emokeor heaL from a ftre

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Airflow meterAleo known aa manometer. Vtaualreadout indtcatee air velocity Lhrou7hLhe fan; when veloctty drope below acerLatn level, ftltera ahould be replaced

Light owitchM uoL be exploaton - proof,or incapable of produc'inq eparko Lhat couldi4nil;e vaporo

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Workpieaethould be poeitionedbetween epray 1un andfan; no large objecLeahould tmpede airf lowbetween workpieceand fan

Waete canFor temporary otor-a7e of combuetiblewa6te; made of eteelwith tight-fitttn4 ltd

Fireertinguiaherthould bemounted ina convenienLlocation y

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Page 105: The Art of Woodworking - Wood Finishing

PROTECTIVE FINISHES

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Light fixtureFeaturee tncandeacent bulb in aeealed 4laee 7lobe that prevenLevapore in room from ignittn7

WallCan be made of con-crete, aheet metal orfire-rated drywall cov-ered wtth aheet metal

T) ecause of the hazards associated withD spray ing f in ishes , the prac t ice isstrictly controlled by law. You cannot,for example, set up a furniture sprayingfacility in your garage without ade-quately guarding against fire and envi-ronmental contamination.

Spraying generates toxic and flam-mable vapors, solvents and particles,making the air in the immediate areaharmful to breathe and potentially explo-sive. Toxic vapors must be filtered outbefore the air can be exhausted; and thesDrav area must be contained in the eventoi fir.. Although water-based productspose less of a fire hazard than solvent-based finishes, making them a safer alter-native for the finisher, both types produceharmful vapors when sprayed.

If you want to spray furniture, youhave two ootions: You can use a com-mercial booth (page B4) or you canbuild a spray room. The latter alterna-tive is a complex undertaking, howev-er. According to one of the regulatoryagencies, the National Fire ProtectionAssociation (NFPA), a spray room mustbe fully enclosed and feature a power-ooerated ventilation svstem.

The illustration at left shows some ofthe elements that might be incorporat-ed in a typical spray room. A powerfulelectric fan pulls air from the roomthrough a panelof filters, which removetoxic substances before the air is exhaust-ed. The walls are constructed in such away as to prevent the spread offire. Theelectrical system is explosion-proof: theswitches, outlets and fixtures willnotcreate a spark or produce a voltage lev-el that could cause an exolosion.

Beiore designing a spiay room, thereare several important preliminary steps.First, consult your local, state and fed-eral inspection authorities to make cer-tain your design complies with the fire,electrical, building and environmentalcodes in effect in your community. Forexample, your spray room will have tomeet NFPA and Occupational Safety andHealth Administration (OSHA) safetyguidelines. Also check with your homeinsurance carrier. You may discover thatoperating a spray room voids your insur-ance policy. Ifyou still see fit to proceed,consult a ventilation engineer who cangive you expert guidance on properlysituating and designing your system.

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Air regulator

Air compreaeor? r e a a t t r i z e a a i r f n r a n r a

eyetem. Located ouLaidea n r A \ t r A A m ' a i e h n a e r t r t' r ' - r ' ' - - - ' - 1 n t n qthrouqh wall connecta tt Loair requlaLor inaide raom

SPRAY ROOM SAFETY TIPS

. Consult the f ire deoartment as wellas pertinent local, state and federalauthorit ies before choosing a site foryour air exhaust outlet. Depending onthe area in which you live, levels of cer-tain contaminants may be restricted byspecific regulations. In general, locatean outlet to avoid exposing passersby,children and pets to the exhaust.

o Check wi th your local author i t iesabout noise regulations; the ventilationsystem in your spray room may createnoise levels that are deemed excessivefor residential areas.

. Keep the walls, f loor and other sur-faces of your spray room scrupulouslyclean to prevent toxic or f lammable sub-stances from accumu lating.

. Always wear protective safety gearwhen spraying: long pants, a long-sleeved shirt, safety goggles, rubbergloves, a rubber apron and a dual -carlrid,ao rpsniratnr

. Replace air f i l ters regularly, as indicat-ed by the airf low meter.

o Dispose of used air f i l ters accordingto local f ire regulations.

. Do not wear clothing or safety gearused during spraying outside of the spray . Store finishing products safelyroom; store these items in a metal locker. (page 136).

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IDENTIFYING AND AVOIDING SPRAY PROBLEMS

I ood spraying technique alone does\J not guarantee first-rate results.Other factors, including the characteris-tics of the spray room, the equipment oreven the weather can also influence thequalityof the finish.

A clean, dust-free work area is essen-tial. One answer is to vacuum regular-ly. If you spray frequently, you shouldconsider setting aside part ofyour work-shop for drying. To prevent any dustfrom settling on a newly finished work-piece, provide yourself with severalmakeshift dust covers. These can benothing more than pieces of plywoodsitting atop tall supports. When you fin-ish spraying a piece of furniture, place itunder a dust cover to catch anydust thatmight otherwise fall on the workpiece.

Humidity and warm temperaturescan wreak havoc on finishes, leavingshellac with a milky look or causing lac-quer to dry poorly. Keeping the roomat the right temperature-roughly72o-isnot quite as difficult as control-ling humidity. It is best to do your spray-ing on a dry day.

Even with optimum conditions andproper technique, snags will arise fromtime to time. If there is a problem withthe spraying system, consult your own-er's manual. Most manufacturers pro-vide detailed troubleshooting guides fortheir equipment. The following chartdetails some ofthe most common spray-ing problems, their causes and ways toprevent them from occurring.

Fisheye

Crazing

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Run Pinholes

DEFECT

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Checking

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Orange peel

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Pinholes

DESCRIPTION AND CAUSE

Fine cracks caused by solvent or materialincompatibil i ty.

Subtle, grid-l ike cracks in the finish caused by a rapidshift in temperature. lf the workpiece is exposed towarm temperatures and then suddenly brought into acold room, the f inish wil l contract at a different ratethan the wood.

Milky-white clouds in the finish usually occurringwhen a finish is sprayed on a humid day.

A rough, "orange peel" texture, the result of holdingthe spray gun too close or too far from the surface,using too l itt le thinner or setting the wrong pressurefor the material being applied.

A large drip that runs down a vertical surface aftertoo much finish has been sprayed in one spot.

Similar to a run, but covers alarger area.

Material that dries before it reaches the workpiecebecause it is being sprayed from too far away.

Small, circular, occasionally ir idescent shapescaused by contamination from silicone or wax fromblades or tools.

Small holes caused by spraying at too high a velocityor by spraying too close to the work surface.

PREVENTION

Make sure your thinner and finishing materials arecompatible, according to the manufacturer'ssoecif ications.

Keep the finished workpiece in a temperature-control led environment.

Spray on dry days; keep the temperature constant.A retarder added to the finishing material on humiddays wil l allow the finish to dry more slowly and coun-teract the problem of the top layer drying too quickly.

Hold the gun at the proper distance from the worksurface-about 8 inches-and adjust the air pressurefor the finish that you are spraying; check the materialviscosity.

Move the gun evenly and more quickly. Reduce thematerial feed adjustment and ensure that the finish isthinned to the proper consistency.

Hold the gun at the correct angle and keep it movingat an even pace. Reduce the material feed adjustmentand check that the finish is thinned to spray consistency.

Hold the gun closer to the surface or reduce theair pressure.

Wipe the workpiece with naphtha and diluted ammo-nia before finishing. Avoid touching the workpiece ifyou have come into contact with sil icone or wax.

Add a moisture retarder to the finishing material; itwil l slow down the drying time, allowing the finish toflow over the holes. Reduce the air pressure and makesure you are using the proper spraying technique.

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FRENCH POLISHING

f, rench polishing is a trme-I' honored method of fin-ishing that involves paddingon shellac with a cloth. Theresult is a lustrous. almostthree-dimensional finish typ-ical of fine antique furniture.The look does not come eas-ily, however. French polish-ing takes time to master anda lot of elbow grease. For commercialwoodworking shops, the labor and timerequirements generally rule out this typeof finish for most jobs; it is much easi-er to rely on lacquers and modern sprayequipment. Still, for an amateur wood-worker, French polishing can be arewarding way-some purists wouldargue the very best way-to finish a spe-cial project. Although the finish doesnot stand up to water, alcohol or heat, itis relatively easy to repair once the pieceis completed.

The materials required for Frenchpolishing are wool and linen rags (piecesof old sweaters and shirts or a well-

PADDING (|N THE SHELLAC

1 Making a padI Take a piece of wool roughly 3 inchessquare and fold the corners toward thecenter, stretching the wool with eachfold. Then squeeze the wool pad into anoval and add a few droos of 2Vz- to 3t/z-pound-cut shel lac. Disperse the shel lacthroughout the wool by crumpling the padin your hand, then place i t in the middleof a single thickness of coarse l inen. Addseveral drops of alcohol Io the pad (right).

washed bedsheet will work fine), shellacflakes, denatured alcohol, mineral oil,pumice and polishing compound.Shellac is measured by the

((6s1"-1ls

number of pounds of shellac flakes dis-solved in each gallon ofalcohol. So, a5-pound cut refers to 5 pounds ofshel-Iac dissolved in a gallon of alcohol. ForFrench polishing, we a 2Vz- to a 3lz-pound cut, although you will, of course,be dealing in quantities smaller thana gallon.

The process consists ofseveral steosthat are done to the following scheduie:On the first day, a coat of oil is appliedto the wood and the excess is wiped off.

After the top of this table wasFrench polished, the legs weregiven a similar look by brush-ing on three coats of shellacand then wiping on a fourthcoat with a pad.

Then the pores are filled with pumice.On the second day, additional coatsof shellac are padded on to build upthe body of the finish. On the third day,the oil film is removed with a cleancloth. This is the time to examine thesurface under a light and build up thebody where you notice dull spots oropen 8ram.

Ifyou cannot afford the time requiredfor a French polish, there are substitutescalled padding lacquers that provide asimilar look without the same level ofeffort. Padding lacquers are frequentlyused to reDair old finishes, but can alsobe applied to new wood.

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ff'ffi'"llr{l-lll'ffi9HO7 Tt?Making a pumiae diapeneerjome finiehero u6e a oaltshaker to oprinkle on pumioefor French poliehing (page 1OB,otep 3),Ycju can also fashiona more traditional disoenser.?our a smal l amount, of pumiceinto a piece of linen. FolAthelinen over and lie the too wilha emall piece of etrrinq io forma ball. To use Lhe diopeneer,ehake the baq, opr inkl inq asmal l amount, of oumiceNhrouqh Lhe cloLh and onNothe wood.

r') Preparing the padL tor French polishingGather the l inen around the bal l of wooland twist the l inen unt i l the pad is heldfirmly in place (above, ieff). Then tapthe pad against the palm of your handto spread out the shel lac and alcoholand form a flat surface (above, right).lf the pad is too wet, squeeze out theexcess l iquid. (When not in use, the padshould be stored moist in an air t ightcontainer to prevent it from stiffening.)

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Q Fi l l ing the poresr-, , Apply a sealer coat of shel lac with a brush and al low i t todry. (This procedure can be done before making the pad.) Thensprinkle pumice on the workpiece and shake a smal l amount onthe pad. Grip the pad t ight ly between your f ingers and thumband work the pumice into the wood with any of the strokesshown in the diagram below; choose the one that proves mostcomfortable. Keep the pad moving whi le i t is on the surface toprevent the alcohol on the pad from Ieaving a mark on the wood

(above). Pay particular attention to the edges so as not to leavethem untouched. At f i rs t , the pumice wi l l sound scratchy as yourub. The more the pores f i l l , the less scratchy the pumice wi l lsound. Cont inue to pad, occasional ly spr ink l ing on f resh pumiceand adding more a lcohol , unt i l the pores are complete ly f i l led andthe surface has a matte look. Depending on the size of the work-p iece, th is procedure may requi re 30 minutes or more. Af ter f i l l -ing the pores, set the workpiece aside for a day.

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POTISHING PATTERNS

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PROTECTIVE FINISHES

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Bui lding up the f i lmPrepare a new pad and dab a drop of oil onto it with a fin-

ger to provide lubrication for padding the surface (above, left).Pol ish with the same strokes you used to f i l l the pores. Uselight pressure with a wet pad. As the pad dries and the frictionincreases, apply more pressure. Recharge the pad with shellacand alcohol, as needed. Repeat the process until the look of thefinish pleases you and the polishing streaks disappear (above,righil. SeI aside the workpiece f or a day . After the shellac has

dried you wi l l not ice a mi lky clouding of the surface, as in theupper half of the workpiece in the pholo (below). This is theoi l used to lubr icate the pad; having r isen to the surface i tmust now be removed. Moisten a pad with alcohol and rubthe surface with long strokes (or polish with a fine glazingcompound) unt i l the oi l disappears. This wi l l reveal the f inailook of the French polish as shown in the lower half of work-piece in the ohoto.

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ing results are usually obtainable witha little patience. The glaze is brushed,ragged, combed, sponged, or evenqpattered over an opaque base coat Inall decorative finishes except stencil-ing, the color of the base coat is vis-ible ttroughthe glazewhich imparuto the finish a deep, subtle glow. It isgenerally a good idea to mix moreglaze than you think you will need,because it is next to impossible tomatch such a finish exactly. The realchallenge of decorative painting

In contrast to the violent natural forces that create real mar-ble, this bird feather requires a deft touch to transform tintedoil paint and a ghze coating into a marble finish on wood.

II

DECORATT\C FINSHES

ecorative painting traces itshistorybackto about 3000 BC,

when artisans h Egfpt, hrdiaandtheOrient leamed to transform ordinarymaterials and obiects into omamentalones ttrough marbling graining sten-ciling and other practices. Along withmore ftaditional prizes of the tradingroute, the techniques of decorativepainting were carried to the West,where they have cycled in and out offashion dor,vn through the centuries.Stenciling, in particular, found favoramong the early colonists of NorthAmerica. Colonial furnituremakers used stencils to embellishtheir inexpensive chairs; householders of modest means sten-ciled their rough floors and plaster walls to mimic the beau-ty of the wallpaper and rugs they could not afford. During theVictorian era, artisans both in the United States and abroadtook inspiration from the futs and Crafts Movement, elevat-ing the faux (or false) finishes-marbling and graining-tothe realm ofhigh style. In the hand ofan expert, a pot ofglazeand a feather could transform bland tabletops and small box-es into rich marble look-alikes; a deftlywielded graining brushcould give an item of plain pine furniture the luxurious lookof walnut burl.

While the techniques and materials of stenciling changedlittle over time, the methodology of marbling and graininggrew ever more refined. Close-mouthed professionals kepttheir trade secrets close to the vest, even carrying the par-ticulars of their artistrywith them to the grave. Novices maynot be able to duplicate the finishes of the masters, but pleas-

Stencilinghas developed from a crude interiordecorating technique into a minor art form.

The top rail of this Boston rocker, stenciled withbronze powder, is typical of 19th Century designs.

is in the patterning of the glaze.Stenciling is the least complex technique-you can just stip-ple the color on over the base coat with a brush or a sponge,working through a paper or acetate template. Marblingand graining are more difficult to execute, because bothcolor and pattern must be fairly realistic for the finish tobe attractive. In marbling, this means you must first cre-ate a believable cloud ofbackground colors, then shootit through with natural-looking veins. Because the pat-terns of heartwood and sapwood are less free-flowingthan the veins in marble, graining requires even moreskill than it takes to disguise wood as marble. In bothcases, finishing will go more smoothly if you continual-ly refer to a sample of the material you are trying to sim-ulate. With any decorative finish, always test theappearance ofthe glaze over the base coat before begin-ning work; with marbling and graining, practice pat-terning on large pieces ofillustration board until you areconfident of your technique.

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TOOLS AND ACCESSORIES

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Marine epongeFor removing excego4laze and eoftening7rain and marbledpatterna; featureaa naturally rou4haurface

Graining combsFor deeigning wood grainpatternz on a workpiece; fea-ture metal or rubber teeth

9wivelknifeA precieionartiet'a knifewith a awiveling tip for Badger softener

A epecialty bruahuaed for aoftening

cuttinq contoura of atencila

qrain and marbled pat'terns, and amoothinq out Camel's-

hair awordd ecorative finiahea; madeof fine badger hair atriper bruah

Afine, aoft bruah uaedto apply individual veinaor qrain linea in freehandgraininq and marblinq

1tenciling bruohFor applyrnq paint orbronze powdere throu1hatencil openin7o; haa atiffh o4'o-h air briatlee thathelp prevent paint frombleedinq under atencil

Hog'a-hairbriatle bruahFor applyinq thebage coat andremoving etainin4qlaze when producinqwood qrain patterna; ite

Bloak cuahion grainerFor creatinq wood 7rainpatterng on a workpiece.Fulled and rocked alonqthe eurface of a qlazedworkpiece at any anqle;featurea a rubber face

flaqqed briotle tipa promotemaxtmum coveraae

qlaze in marbledfiniahea; worka beat wheneli7htly worae for wear

Orainin7 rolleraFor producing woodqrain patterne on aworkpiece; pulled acroeea qlazed surface

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STENCILING

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Designs are generally stenciled with either paint (above,left) or bronze powders(above, right). The application techniques are dffirent, as are the range of fficx.Bronze powders, for example, can create a burnished, three-dimensional look.

MAKING THE STENCIT

F u..r since the l8yptians in ancientIJ tlmes began decoratrng mummycases with stencils, such decorative pat-terns have been a ubiquitous feature offurniture design. They have appearedon everything from shields to chairs andtoy chests.

As simole as a fine-veined leaf or ascomplex is a multicolored, repeatingmotif of fruits and flowers, a stencil canbe applied to a piece of furniture eitherbefore or after the last coat of finish. Thestencil is typically reduced or enlargedfrom a master Dattern and cut from

either stencil board or acetate. Becauseacetate can be cleaned with mineral spir-its and reused, it is more durable thanpaper. The translucent material can bebought at most drafting supply stores.

Stencil designs can be sprayed on orapplied with a special short-bristled sten-ciling brush. While earlyAmerican set-tlers stenciled with milk paint, anythick-bodied paint, such as quick-dry-ing japan colors or an oil-based or acrylicpaint, will fit the bill equally well. Bronzepowders can be combined in the samestencil to yield a variety of metallic col-ors within a single design, creating theillusion of light and shadow-a tech-nique made famous by the Hitchcockchairs of the mid-1800s.

1 Enlarging a patternI One way to produce a larger versionof a pattern for stenciling is to use a pho-tocopier with an enlargement feature;another way is to transfer the shape usinga grid. Draw a grid of squares over the pat-tern, using a ruled straightedge to makeall the squares exactly the same size. (Thesmaller you make the squares, the easier itwill be to reproduce the pattern.) Then, on ablank sheet of graph paper or acetate, makea larger gr id, increasing the size of thesquares by the same amount you wish toenlarge the pattern. For example, if youneed a stencil design that is twice the sizeof the pattern, make the second set ofsquares twice as large as the first. To pro-duce the stencil design, draw in each squareof the enlarged grid the part of the patternthat is in the corresponding square of thesmaller grid (left). To make a stencil small-er than the original pattern, follow the samesteps, but make the second grid smallerthan the f i rst one.

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r) Cutting out the patternL f ransfer your design to a pieceof stencil board or acetate. With thes tenc i l board , use carbon paper ;for an acetate stenci l , s imply placethe sheet over your design and tracei t in ink . l f your des ign w i l l inc ludemore than one color, make a sepa-rate stenci l for each color. Use aswivel knife to cut out the pattern,pulling the knife toward you bbove).Keep your free hand out of theblade's oath.

lllr ilt ulr filj llll illt lllt lllt flll llll llll llll flrl lllJ llll lll1 rllj llll?HO? TI?Trojecting a ?atternAnother way No reproduce a stencil in a differenL eize involveeVrojeclinq Nhe deoiqn onXo a wal| First Iake a phoboqraVh of lhepatlern ueing elidetilm.Io avoid distnrtion, ehoot,from direcNly infronL of Nhe pat1ern. )nce Nhe film is develoVed uoe a slide projec-Ior No dieplay lhe patlern on a wall.The t---dislance between Lhe projeclor and Lhe 1 .r , -wall will Aetermine the size of the imaqe

| "S€4"wall will def,ermine the size of the imaqe, | . d?.S:bToNransferLhepattern,projectthe

- I ' g$g^-.@"

image onto a pibce of etencil board i o*{&3/6

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or aceXate and lrace over it,.

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PAINT STENCILING

lllt fitl ll11 llll iltl tlll lll lllt filt tlll illt IIJ tlll llll fllJ ilIj ilIl rlll1HO? TI?A cure for bleedingTo prevenN wet, paint, from bleeding under a slencil,Nemporarily bond Ihe etencil Io your workViece.7pray Nhe undereide of Nhe eNencil wilhan aeroeol adheeive,Nhen placeiNin Voeilion on Nhe work'piece, preooinq outany air pocketo.App ly the Va in ia5 soon a5 ?o5-sible so thal youcan peel off thestencil before il

' l Taping down the stencilI To help al ign the stenci l precisely,draw a reference l ine centered alongeach side of both the workpiece andthe s tenc i l . Then secure the s tenc i lto the workpiece with masking tape,making sure the reference lines matchup properly (abovd.

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DECORATIVE FINISHES

Applying the paintTransfer the stenci l design to your workpiece by spraying

or brushing on paint. l f you are spraying, mask the surfacessurrounding the stenci l with paper and set the workpiece edgeup on a work surface. Holding an aerosol paint can about 6 to10 inches from the workpiece, direct the spray at the stenci luntil the exposed wood is coated lightly with paint bbove, lefil.To prevent pa in t f rom b leed ing under the s tenc i l , keep thenozz le leve l w i th the s tenc i land spray in a s t ra igh t l ine . To

use a stenci l ing brush, set the workpiece f la t on a work sur-f ace and d ip on l y t he t i ps o f t he b r i s t l es i n t he pa rn t . Th i s w i l lr esu l t i n a l i gh t coa t and thus reduce b leed ing . Ho ld ing theb rush pe rpend i cu la r t o t he su r face , j ab t he b r i s t l es up anddown on the stencil unti l the wood is covered (above, right),re loading the brush as necessary. l f you are us ing more thanone stencil to apply several colors, let each coat dry beforespraying or brushing on the next .

Removing the stencilTo avoid any b leeding, remove the

s tenc i l wh i le the pa in t i s wet . Pee l themask ing tape f rom two ad jo in ing cor -ners, then gent ly l i f t the stenci l of f theworkpiece, pul l ing up the two sides evenly ( lef t) . Avoid sl id ing the stenci l alongthe surface or you may smear some ofpaint. Once the parnt is dry, remove anyadhesive residue with naphtha before top-coat ing the workpiece.

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BRONZE POWDER STENCILING

Rubbing on the powdelWi th the varn ish s t i l l tacky , wrap a

p iece o f chamois o r a c lean, so f t c lo tharound your index finger and dip it into thebronze powder . Rub the powder on tothe surface exposed by the cutouts in thestenci l . Rub the areas you wish to high-l igh t re la t i ve ly hard ; rub more l igh t lyon areas you want to shade. Apply addi-t ional powder as necessary unt i l the sur-face is colored to your sat isfact ion, butwork qu ick ly to keep the varn ish f romdry ing comple te ly be fore you are f in -ished. Then peel of f the stenci l . To high-light the three-dimensional quality, applyseveral layers of bronze powder, separatedby thin layers of varnish. When you are fin-ished stenci l ing, protect the surface withtwo f inal coats of varnish

1 Positioning the stencilI Draw the stenci l on acetate andcut out the pattern. Place the bronzepowder in a bowl or on a palette andset it aside. Prepare the workpiece byapplying a thin coat of slow-drying var-n ish to the sur face you w i l l be s ten-c i l ing . Le t the varn ish dry un t i l i t i sf i rm but st i l l tacky. Place the acetatein pos i t ion on the workp iece g lossys ide down so tha t i t adheres to thesurface (left).

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GRAINING

f raining is a process in which the\f appearance of one type of wood isre-created on another for decorative pur-poses. On species with muted grain, thetechnique can be used to imitate the tex-ture and warmth of moreexotic species. But grain-ing can also camouflagevisual defects-like a woodpatch used to repair a dam-aged surface. Wth practice,exoerimentation and care-frrl study of the species youwish to emulate, you canproduce a diverse range ofstyles, from the close grainof beech to the free-flow-ing pattern of pine.

Graining was especial-ly popular in the 1800samong westward-movingAmerican pioneers. With hardwood inscarce supply, woodworkers harvestedsoftwoods and grained them to resem-

GRAINING A SURFACE BY HAND

1 Preparing and applying the glazeI Tint a container of flat oil-based oaintwith artists' colors so that it matches thehue of the wood you wish to imitate.Spread a layer of the paint on your work-piece as a base coat and allow it to dry.Then apply a graining glaze on the paint-ed surface with a foam brush or pad appli-cator. To begin the process of creating agrain pattern on the wood, wrap a softcloth tightly around three of your fingers,then draw the cloth along the surface sev-eral t imes, drawing thin, wavy, paral lellines (right).

ble more highly figured woofu like cher-ry, oak and mahogany.

Graining involves several stages. First,the surface is painted with a flat basecoat and the base is allowed to dry.

A deftly wielded artist's brush and a grain-ingroller combined to etch avivid pattemofheart grain on apiece ofparticleboard.

A color glaze is then applied and thegrain pattern is traced into the glazewith special graining tools such ascombs, raymarkers, mottlers and rollers.Finally, a protective topcoat is added.

Graining glazes canbe prepared in the shop,but commercial, ready-to-use glazing stains are justas effective; they can betinted with japan colorsto produce virtually anyshade you wish. The glazesyou make yourself willusually consist of one partboiled linseed oil and twoparts varnish; they are tint-ed with artists' colors. Youneed a heavy-bodied con-sistency, but not so heavythatthe dryingtime is slow

or the grain patterns will tend to flowback together. You can buy special addi-tives to speed up the drying time.

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Q Drawing in knotsr. , l Wrap a cloth around one f inger anddip the f ingert ip in the glaze. Then gent lytouch the surface to make Iheknol (righil.To smooth out the oatterns and blendthem into the background, brush the sur-face back and forth with a soft, dry brushfollowing the direction of the grain. A badg-er softener is ideal for this stage of theprocess. 0nce the surface is dry, apply atopcoat, then polish it with rottenstoneand paste wax.

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r) Refining the grain linesL fo make the grain lines from stepI a l i t t le more del icate, dip an art ist 'sbrush or a camel 's hair sword str iper inthe glaze, and draw i t s lowly along thesurface within the original lines (left).For best results, hold the brush at anangle to the surface. lf you wish to sim-ulate a knot on your workpiece, rub inlines for a rough oval or diamond shapearound where you w i l l be add ing theknot. Experiment with the brush unt i lthe surface has the grain pattern youare seeking.

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W()RKING WITH GRAINING TOOTS

1 Simulating other grain patternsI Spread a base coat of tinted paint and then a glazing stainfollowing the procedures described on page 118. To simulatethe random grain markings character ist ic of oak, run a raymarker along the surface of the board in straight lines, parallel

r) Blending in the grainL Wnle the glaze is stil l wet, gently drawa soft, dry paint brush, such as a badgersoftener, back and forth over the surface,following the direction of lhe grain (right).This wi l l fan out the grain l ines and givethe surface a more uniform and naturalappearance.

to the edges (above, left). To reproduce the broad grain patterntypical of mahogany, draw a metal or rubber graining combalong the surface, creating a series of slightly wavy but paral-lel lines (above, right).

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A BLOCK CUSHION GRAINERWith a molding j ig and si l icone rubber,you can make a block cushion grainerto suit your needs. For the jig, cut a cir-cular block of 1%-inchthick wood thatwi l l f i t on the sandrng disk of your elec-tric drill. Screw the block to the disk, theninstal l the disk in the dr i l l chuck. Attacha commercial drill stand to a %-inch ply-wood base, then instal l the dr i l l . Clampthe base to a work surface and secure ashort scrap of 2-by-4 just in front of theblock to serve as a tool rest. Cut notchesin the 2-by-4 for clamps.

To shape the wood block, lock the drillin the 0n position and hold the tip of asmal l skew chisel against the rotat ingsurface, etching a %-inch-deep grooveinto the wood. Rest the chisel blade onIhe2-by-4 to keep it steady. Cut on theleft-hand side of the block to prevent thechisel f rom being kicked up. Carve aseries of concentric grooves in the block(above,right), varying their widths and theintervals between them to suit the grainpattern you wish to desrgn. Closely spacedgrooves will produce a hardwood look;grooves that are spread farther apart arebetter for simulating softwoods.

To make the actual grainer, remove theblock from the sanding disk and coat itsgrooved face with paste wax. Then applya 7a-inch-thick layer of s i l icone rubberover the wax. Let the rubber cure forabout24 hours, then peel it off the block(below, righil.frim the rubber imprintand glue it to a rounded piece of 2-by-2with a plywood handle. Remove any resid-ual paste wax with naphtha.

The tool is used the same way as tradi-tional grainers (page 120), but rememberto push it along the surface with a forwardrockrng motion.

Drill/ V Jig baoe

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MARBLING

f n the past, when structural consider-I ations ruled out the use of realmar-ble, faux marbre, or false marble, finisheswere commonly used as a substitute oneverything fiom walls and floors to man-tels and furniture.

Real marble is a bv-product of intensenatural forces that occur when limestoneis melted under great heat and pressure.Minerals running through the molten

rock cool and crystallize. The result islayer upon layer of veins colored white,black and other hues, which togetherform a lattice that is somehow bothopaque and translucent.

Of the many techniques for replicat-ing the appearance oimarble on wood,most involve working with two or threecolored paints on a wet, glazed surface.Tools for manipulating the paints range

from rags to newspapers to sponges, Finebrushes or a feather are the best imole-ments for simulating the depth and pat-tern ofthe veins.

As a rule of thumb, the colors on amarbled surface should be limited to amaximum of three, including the basecolor. The choice of colors is best restrict-ed to the natural colors found in mar-ble. The constituent oarts of marbleactually flow during the formation ofthe stone, and it is vital to capture thisappearance offluidity. To produce a real-istic design, work with good referencephotographs or keep a sample of the realthing on hand.

White and green ntarbled woodsimulates the Jluid appearanceand misty depth of real marble.

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MARBLING WITH A BRUSH

1 Applying the glazeI For the base coat of a white marblef in ish, brush a coat of white, semiglosso i l -based pa in t on your workp iece as abase coat and a l low i t to d ry . To e l im i -nate any brush marks, l ight ly sand thesurface with a 320-gr i t sandpaper. Tinta container of white glaze with a smal lamount of one of the art ists ' colors thatyou w i l l be us ing in the f in ish . Then usea cloth or a creased piece of newspaper tocoat the painted surface wilh glaze (righil.

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r) Sketching in the marble veinsL Wntle the surface is stil l wet. squeezesome of the art ists ' color used in step Ion to a pa le t te . D ip an ar t i s ts 'b rush in tothe color and use wavy strokes to paintimitat jon-marble veins in the glaze (above).The veins should aooear to wander random-ly about the surface, forking r ight and lef t .Ro l l ing the brush be tween your f ingerswhi le you paint can also produce a real is-t ic ef fect. Once you have painted in al l theveins, remove the excess glaze and softenthe ve ins by pu l l ing a so f t c lo th d iagona l lyacross the surface (ighil. Repealthe processto paint in more marble veins in a secondcolor. lf you wish to layer on additional veins,reverse the order of the colors, or mix themtogether to provide contrast and depth tothe surface.

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n Smoothins the oattern<.

r - ,1 Whi le the sur face is s t i l l wet , gent lydraw a sof t , dry paint brush, such as abadger softener, back and forth acrossthe veins (right). Conlinue unti l the sur-face looks misty and t ranslucent . Oncethe sur face is dry, le t i t s i t for abouI24hours and apply a coat of semigloss orh igh-g loss polyurethane varn ish. Pol ishthe workpiece wi th a sof t c loth.

FEATHERING A MARBLED SURFACE

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1 Sketchins broad veinsl -

I Fo r a g reen marb le f i n i sh . sp reada base coat of green paint and then ag laze t i n ted a l i gh te r co lo r on you r wo rk -p iece fo l lowing the procedure on page1 2 2 t \ ' i n : h i r d f p : t h p r i n i n t h p o l a z p

i r i r v ! i ' v b i v 4 v

and d raw i t d i agona l l y ac ross t he su r faceto produce broad marble- l ike veins ( /ef f ) .

Smooth and sof ten the pat tern by brush-ing the veins l ight ly wi th a mar ine sponge,a badger sof tener or a sof t c loth. Whi lethe sur face is s t i l l wet , prepare anotherbatch of g laze and t in t i t l ighter than thef i rs t coat ing. Apply and feather th is g lazethe same way you d id t he f i r s t one , bu tth i s t ime , make the ve ins c ross ove r t heones a l ready i n p lace .

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r) opening up the patternI lo produce a mottled effect on thesurface, dip a clean, st i f f -br ist led paintbrush into a container of mineral spir i ts.Holding the brush a few inches above theworkpiece, run a gloved f inger along thebrist les, moistening the veins with a f inespray (right).

Q Completing the patternr-,, Dio a bird feather in white artists'color and allow the excess to drio offto prevent any blobbing. Then use thefeather tip to sketch in a series of thinwhite veins within the broad veinsalready on the surface. When al l thefine veins have been painted, smooth,varn ish and po l i sh the sur face asdescribed in step 3 on page I24.

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The varnish topcoat on this lgth-Century farm-house-style table was rubbed out with extrafine steel wool and buffed with paste wax.

The difference between a rubbedsatin finish and one that is buffed toa gloss depends on the grit of theabrasive you choose. Rubbing com-pounds, for example, contain par-ticles that leave minute scratcheson a surface. Coarser-grit com-pounds produce a fairly large pat-tern that makes the surface appeardull, or satin. Finer-grit compoundsleave marks that are harder to see,creating a glossier look. Virtuallyanything that abrades can be used

Fitted with a lamb's wool buffing bonnet, a random-orbitsander serves as an electric polisher, rubbing out the finishand then buffing the topcoat to a high-gloss sheen.

FINSHNGTOTICHES

Ithough woodworking cat-alogs abound with a wide vari-

ety of rubbing compounds andfancy electric polishers, purists stillrely on the centuries-old process of"rubbing out" a finish with tradi-tional abrasives. Rubbing a finish toa satin sheen with pumice, a pow-dered form of volcanic rock,imparts a soft look suggestive ofbrushed brass and leaves the woodsmooth and silky to the touch.Taking the process yet another stepfurther with an even finer powdercalled rottenstone removes the abrasions caused bythe pumiceto add an extra measure of shine-even to glossy topcoats ofvarnish or lacquer.

The notion of rubbing out a meticulously applied topcoatwith abrasive compounds mayhave an incongruous ring to it.But the final coat of finish on a piece of furniture seldomleaves the surface clear and perfectly smooth. It is not unusu-al for the topcoat to be speckled with random dust and dirtparticles that settle on the finish before it dries. In addition,some "signature" of the tool used to apply the finish may bevisible. Even when brushes are adroitly handled, they oftenleave behind faint bristle marks, and a sprayed surface mayshow a texture similar to that of an orange peel. The first stepin the rubbing process therefore is to level the surface as per-fectly as possible. The smoother it is, the better the look andfeel of the topcoat. Once the surface is level, it can be buffedto almost any sheen.

for rubbing out. In addition to rub-bing compounds, finishers rely on sandpaper, steel wool andnylon abrasive pads. In each case, the size ofthe scratch pat-tern dictates the level of sheen.

If rubbing out has an inherent problem, it is the risk ofrubbing through the finish. Since the process involves grind-ing small amounts of the thinlylayered topcoat, there is alwaysthe possibility of cutting right through the coating to thewood. You need to be especially careful near the edges. Withsome varnishes, rubbing through even the very top layer willcreate a blemish. The resulting outline of the cut area, calleda "halo" or "witness linel' is a faint but visible reminder ofjust how thin each layer of a finish really is.

While most of the rubbing out process is a removal ofmaterial, the last step puts a tiny amount back. Waxing asurface adds an ultra-thin layer of protection atop therubbed topcoat, imparting a little more sheen and dura-bility to the finish.

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TOOLS AND ACCE,SSORIE,S

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LubriaantKeepe pumtce from remov-inq finteh when aLeel wool orabraetve pado are ueed Lorub ouL f intoh; potaearum'oleate type re 1enLle enouqhto be ueed as cleaner

Kubbing oil)peeda up rubbing ouL proceee; uoed with eandpa-per or pumice etone to achteve a hiqh-qloae ftntoh

Paste waxDuffed on eurfaceafLer rubbin7 ouL1;o produce a water-regietant and lonl'Iaoting lueLer finiah;blended waxeg areoften made wtLhcarnauba, a hard,naLural wax, mtxedwtth parafftn orbeeewax

Pumice etoneMedtum coaree (2F)and fine (4F) qradeeoprinkled on aurfaceand ueed with feltblock; made fromqround up lava

Felt. blockFelt-covered hard-wood block farepreadtng ,rubbin4co,mP,ouna on nn'tSnea 6urface

An abraeive paate epecially formulat.'ed for rubbtn4 out lacquer, varnteh andehellac finiahea; applrcd wtth a raq or

Kubbing aompound

electric polteher RottenatoneA fine abraeive powder eprinkled onaurface aff,er pumtce to achteve a hi7h-qloee oheen; uaed with felt block

Lamb'a woolbuffing bonnetlnetalled on elec'trtc poltoherElectric polieher

Ueed wtth bufftn4bonnet and rubbingcompound to worKon larqe aurfaces

Rubbing pada9uper fine padueed alone or wtthlubrtcant, such aarubbin7 otl; madefrom durable poly'eater frber

Steel wool)uper fine or OOOOqrade ueed for rub-bin4 ouL a ftnioh

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PREPARING TO RUB OUT THE FINISH

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ff aving graced your workpiece withI I a finalcoat of finish and waited forit to dry, you maybe impatient to moveon to the next step. However, before atopcoat can be rubbed out, it must firstdry and set, so as to be hard enough tobe worked over with very fine abrasives.Before rubbing out your workpiece, youmust wait for the toDcoat to cure-thatis, you must allow it ample time tobecome as hard as it will set. Withouttime to cure, you are likely io scratch thefinish during the rubbing out phase.

No two finishes take the same amountof time to cure. The duration of theprocess depends on several factors,including the type of finishing productyou use, the number of coats you apply,

and the amount of time that elaosesbetween subsequent coats. For example,shellac and the water-based finishes canusually be rubbed out after 24 hours.For lacquer, the wait is more like 48hours, while varnish takes three or fourdays. Oil finishes can require weeks tocure. The greater the number of coatson a surface, the longer the curing time.But remember that a finish cures morerapidly if more time is left for dryingbehveen coats. Always read the instruc-tions before apphng a finish; a suggestedcuring time will usually be indicated.

The type of sheen you end up withafter rubbing out a finish hinges on theabrasives you use. For a satin gloss, use400-grit paper, then buffthe surface. Use

0000 steelwoolin conjunction with 400-grit paper for a semigloss. An even finergrit sandpaper, such as 600, combinedwith rubbing compound will result in ahigh gloss. The same effect can also beachieved with a 600-grit paper andpumice or rottenstone.

Start by abrading the topcoat to amatte sheen. If you choose a wet/drysandpaper, select a grit that is finer thanthe one used to prepare the surface forthe finalcoat of finish. The next steo is toremove dust and sanding parricles (page42),Ihen repeat the abrading process sev-eral times with successively finer-gritpapers. For a dull- or flat-looking sur-face, stop at 400-grit paper. Move up to ahigher grit for a glossier finish.

TESTING A FINISH T() SEE IF IT IS CURED

Checking the finishPerform the fol lowrng simple tests todetermine whether a topcoat has cured.Try to d ig a f ingerna i l in to the f rn ish onan inconspicuous part of the workpiece(lefil. You should not be able to leave anindentat ion. l f you do, the f in ish needsadd i t iona l cur ing t ime. Smel l i s anothergood indicat ion. l f you can detect theodor o f the so lvent on the workp iece ,the topcoat i s no t ready fo r rubb ingout . Once the f in ish passes bo th o fthese tests, sand a hidden area l ight ly.l f the paper clogs, al low more t ime forcur ing. l f the paper gl ides over the sur-face, turning some of the finish to powder,the topcoat is ful ly cured.

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RUBBING OUTAFINISH

f here are two competing schools ofJ. thought on the best way to rub out

a finish. The traditional approach is topainstakingly work pumice and rotten-stone over the topcoated surfaces using afelt block. A less hidebound methodinvolves the use of one or more modernabrasives, such as rubbing compounds,steel wool or sandpaper, and may evenmake use of an electric polisher. Bothmethods have their advantages. Workingwith pumice and rottenstone is labori-ous, but wins the woodworking purist'sstamp of approval. The modern way iseasier and cuts down on elbow grease,but some argue that it involves less craft.Both methods are demonstrated on thepages that follow

Whichever route you take, keep inmind that the finer the abrasive you use,the glossier the sheen you will produce.The photo above shows one sheen youcan achieve using either rubbing outtechnique. Any luster can be enhancedby buffing the finish with wax. But donot rely solely on the wax to heightenthe gloss; it will not turn a satin finishinto a semigloss, for example. Instead,the wax will only intensify what isalready there. Although all the surfacesof a workpiece will have to be rubbedout, pay particular attention to tops,since they are the most visible featuresof most furniture.

If you choose to go the traditionalroute, you will need to use a lubricantwith the pumice and rottenstone. Waterand oils, like paraffin and mineral oil,are the most commonly used lubricants.Working with water offers two advan-tages: It cuts pumice more rapidly thanoil, speeding up the process, and it alsodoes not leave any oily residue. Avoid

using water on shellac, however; it willturn the finish white. Paraffin oil. thetraditional rubbing out lubricant, is abetter choice for shellac topcoats.

Rubbing out with fine steel wooland 400-grit sandpaper added a

semigloss sheen to the wood sampleat right. To create a glossier look,

even finer abrasives would be used.

Strokes suitable for a flat surfaceFor tabletops and other flat surfaces, keep every stroke parallel to the woodgrain, as shown in the diagram at r ight. Start near a corner and move in astraight l ine along the edge, rubbing the surface with moderate pressuref rom one end to the o ther . A l te rna te d i rec t ions w i th each subsequentstroke until you reach the other edge. Keep the abrasive moving; the fric-tion resulting from rubbing a single spot too long may leave the finish slightlyburned. Avoid making arc-like strokes, which are apt to make any scratcheson the surface more vis ible.

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A GUIDE T(l THE LAST STAGE ()F FINISHING

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FINISHING TOUCHES

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W()RKING WITH CONT()URED SURFACES

Rubbing out a contoured surfaceFor rounded surfaces that are awkwardto work with a rigid abrasive pad, use ashop-made rubbing pad that wi l l fo l lowthe curves of your workpiece. lf you areworking with pumice, spr inkle i t on thesurface with a short, stiff-bristled brush.Then wrap a sheet of sandpaper arounda thick sponge smal l enough to comfort-ably gr ip in your hand. Clasp the paperaround the sponge as you rub out the fin-ish on the surface (r ight) . With sometypes of finishes, you can also use steelwool or a commercial rubhins nad

RUBBING OUT A FINISH WITH ROTTENSTONE

1 Applying the lubricantI Dip the t ips of your f ingers in a bowlof the lubricant and sprinkle several dropson the surface to be rubbed out (lefil.Wear rubber gloves i f you are using oi las a lubr ican t .

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r) Abrading the surfaceL Snat<e a l i t t le oumice onto the sur-face, then begin l ight ly abrading the sur-face with a fel t block ( /ef t) . Fol low thepat te rn shown on page 130. l f you donot have a fe l t b lock , wrap a p iece o fburlao around a scrao of wood. Cont inuerubb ing the sur face un t i l a mix tu re o fthe rottenstone and lubr icant forms. Usea soft c loth to wioe off a smal l area ofthe sur face per iod ica l l y to inspec t thef inish. You want to make certain that youare not rubbing through the topcoat.

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Q Removing the pumice and lubricantr- ,1 Wioe off the abrasive and lubr icantwith a clean clolh (right). Check the sur-f a c e s h e e n ; t h e f i n i s h s h o u l d h a v e as a t i n l u s t e r . Y o u c a n e i t h e r s t o p t h eprocess a t th is po in t o r repeat i t toobtain a slossier sheen.

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FINISHING TOUCHES

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MORE RECENT ()PTI()NS F()R RUBBING OUT

Using an e lect r ic pol isherF i t a bu f f i ng bonne t on the mach ine ' spo l i sh ing d i sk and sp read a wood rub -b ing compound on the bonnet . Star t thepo l i she r nea r t he cen te r o f t he su r faceand work out toward the edges, movingthe bonnet continuously (left). Electricpol ishers work quick ly , so stop the tooloften and wipe off a small area of the sur-face wi th a c loth to check the condi t iono f t he t opcoa t . Once the su r face takeson a sat in look, you can e i ther s top theprocess or cont inue wi th a f iner-gr i t rub-b ing compound for a g loss ier luster .

l]lt ljll jjlr lltl llr llil ll|1 lllr llll ilil llr r]l1 llr ]Ir lltt ll11 llll illl1HO? TI?Keeping a buflingbonnel grit-freeTarLicles of dust or qr i lon a buffinq bonnef, canruin a Nopcoaf, durinq Lherubbinq oul proceee. TomaKe eure your ,onnet6tayo clean, never seLildown on poLenLially duetysurf ac es. I nsNe a d, resli l on a c lean p laoNic baq.Sef,ween finiohinq jobo, otorethe bonne t , i n a sea lab len l a a l i r h a n

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FINISHING TOUCHES

Using rubbing compoundsScoop up a l i t t le rubbing compound witha clean cloth and rub i t along the woodsurface (righil as you would pumice. Onceyou have abraded the en t i re sur face ,wioe the comoound off the surface withanother cloth. For a glossier sheen, repeatthe process with a f iner-gr i t compound.To obtain a softer gloss than is possiblewi th rubb ing compound, some f in ishersr u b o u t t h e f i n i s h w i t h a l u b r i c a n t a n dsuper f ine s tee l woo l o r a commerc ia lrubb ing pad.

CLEANING AND REPAIR TIPS F()R FINISHES

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FINISH

Lacquer

She l l ac

Varnish

O i l s

CLEANING TIPS

Wipe using clean clothdampened with light detergent,potassium oleate or naphtha;avoid using thinners

Wipe using clean clothdampened with naphtha;Avoid using water; i t wi l l turnshel lac white

Wipe using light detergent,potassium oleate or naphtha;avoid using methyl hydrate

Use naphtha on polymerizedoi l f in ishes; use soap andwater on pure oil surfaces

REPAIR TIPS

Repair cracks with lacquer slick (page 45) or shop-made lacquerputty by letting a small amount of lacquer dry to a honey-like consistency.For white spots, carefully dig out the damage with a putty knife and applylacquer thinner unt i l the white port ion turns clear; then apply lacquerstick or putty, let dry and sand lightly.

Lightly sand away scratches.Repair discolored areas by padding the surface with shel lac as inFrench polishing (page 106).

Repair small cracks or gouges with lacquer stick (page 45).

Sand away scratches, then recoat with oil. Recoat discolored or dull areas.

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FINISHING TOUCHES

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WAXING FOR A PROTECTIVE SHEEN

1 Applying the waxI A coat ing o f wax w i l l p ro tec t arubbed-out topcoat from damage, butse lec t a p roduc t w i th a cons is tencythat is s l ight ly thicker than a l iquid orcream wax. Scoop a bit of the wax ontoa clean cloth, then spread a thin, evencoat on the surface, rubbing the wax intoone small area at a Iime (right). lf you tryto work on too large a surface area aI at ime, the solvent in the wax may evapo-rate before you can rub it over the surface,causing the wax to harden premature-ly . Le t the wax dry accord ing to themanufac turer ' s i ns t ruc t rons , typ ica l l yabout 15 minu tes .

r) Buffing the waxL AuO wi th a c lean c lo th un t i l thewaxed surface shines. For contours orsurfaces with detai ls, as shown at lef t ,buff the wax with a st i f f -br ist led brush,giving the wood short, brisk strokes.

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CLE.A].dING AND STORAGEI

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, \ f in ishing project is not qui te f in-A ished unt i l you clean and put awayyour brushes, store the solvents, and dis-pose of any oily rags. While foam brush-es are usually discarded after a singleuse, bristle brushes and pad applicatorscan be cleaned and reused. With theproper care, a high-quality brush canprovide many years of service.

But good cleanup habits willdo morethan protect your investment; they arealso key elements of shop safety and envi-ronmental responsibility. To keep finish-ing products out of the reach of children,store containers in a locked metal cabi-net. Avoid throwing out wet, oily ragswith the trash; this increases the risk thatthey will catch fire. For temporary storage,

darnpen the rags and place them in asealed rnetal container. This will isolatethern from anv sparks or flames andquickly starve any spontaneous fire ofneeded oxygen. The safest way to disposeof oily rags is to first spread them out todry out ofdoors.

Store finishing products in sealed,properly labeled containers. Avoid usingbottles or jars that normally containfood or liquids; a visitor to your shopcould mistake a chemical product forsomething dr inkable.

Always store stains and finishes atroom temperature; a water-based prod-uct will be ruined if allowed to freeze.Reactive finishes such as tung oilor var-nish, which eventually harden when

exposed to air, should be stored in airlesscontainers. Rather than keeping a smallvolume of a reactive finish in a large con-tainer. transfer the oroduct to a smallerone, exposing the liquid to less air. A bet-ter solution is to buy finishing productsin smaller cuantities or to store them incollapsible plastic containers (page 87).

Do not flush any finishing productdown the drain. Even a water-based fin-ish can pose problems by coagulatingin drain pipes and backing up yourplumbing system. To dispose of smallquantities of a product let it sit in anuncovered container outside until thesolvent evaporates. For larger volumes,consult the waste disposal service inyour community.

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o Avoid standing a brush on its bristles;this may bend them permanently andruin the brush.

. Break in a new brush by suspending itup to the ferrule in a solvent that is com-pat ib le wi th the f in ish you wi l l apply.Soak the bristles for about 10 minutes,then clean the brush with detergent andwarm water.

CLEANING AND STORAGE TIPS

o After breaking in a new brush orc leaning a used one, wrap i t in paperfor storage.

. Salvage a hardened brush by soakingthe bristles overnight in a mixture of 2parts xylene, 1 part acetone and 1 partdenatured alcohol. Use a brush comb toremove fragments of hardened f inishfrom the bristles.

o To dispose of a water-based f inish,pour or brush i t onto scraps of cardboard;let i t dry and discard the cardboard.

. Instead of discarding a container ofused mineral spir i ts, recycle i t . Let thesolvent si t in a cool spot for a week ortwo, then decant the spir i ts that haverisen to the top in a clean containerand dispose of the residue.

SH()P AIDS FOR BRUSHES

Aruah aomb Bruah bucket and lidAn airtiqht 6tora0e con-Latner for ouopendingbruehes in a eolvent;featurea plaettc cltpethat hold bruahee withthe brietlea above thabottom ofthe contatner

A metal comb forcleanin4 eolid ftntEhreaiduee from bruehbristlea

Eruah apinnerUaes cenLrtfu1al force to epin eolventfrombrueh briatlea: one end ofthe devtce holda thebruah while the pump-like handle at the otherend createe the epinning action

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CLEANING AND STORAGE

STORING A BRUSH OVERNIGHT

Soaking brushes in solventThere is no point cleaning a brush (page13B) n you plan to use i t the fol lowingday. Instead, suspend the brush in theappropriate solvent for the f in ishing prod-uct you are using: for varnish, a mixtureof turpent ine and varnish; for shel lac,denatured alcohol; for lacquer, lacquerth inner ; fo r a s ta in , a "b rush keeper "solut ion of 2 parts raw l inseed oi l and Ipart turpent ine. (For oi l -based f inishingproducts, just wrap the brush in plast icwrap.) When soaking a brush, submergeon ly the br is t les , and no t the fe r ru le ,making sure they are suspended abovethe bottom of the container. Keep thebrush in a commerc ia l b rush bucket(page 136), or hang it from a nail in ashop-made rack (above).

llll tlll llll llll illl illt llll llil tllj llll lltJ llll rlll ,lr llil ulJ lt]j ilii1HO? TI??unahing dr ip holeelN Lakes very lif,Lle time for the rimof a can of finish to fil l uo with lia-uid. The result, is ofLen a' meotydripVing and a oVlaoh when the l idie IappeA cloeeA, To keepa conlainer from over'f lowinq i ts r im, punch aseriee of holee aroundiXe circumference wiLh ana i l .Th ie w i l l a l low l iqu idNo fal l Nhrouqh Lhe holeeback inNo Ihe conNainer.

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CLEANING AND STORAGE

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CTEANING A BRUSHI

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1 Rinsins the brush in solventI Submerse the brush's br ist les in theappropriate solvent for the f in ishing prod-uct used (page 16). Swirl the brush in thesolvent, pressing the br ist les against thesides of the container. Work the solventthrough the br ist les with your hands unt i lthe brush is clean ( lef t) . fo remove al l theresidue from the brush, wash the br ist lesin a solut ion of mi ld detergent and warmwater, then pul l a brush comb throughthem as many times as necessary (below).

Page 141: The Art of Woodworking - Wood Finishing

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CLEANING AND STORAGE

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r) Spinning the brush dryL to r id a brush of solvent, shake rt byhand or use a brush spinner. In both cas-es , ho ld the brush ins ide a 5 -ga l lon canto catch the solvent as i t sprays from theh r i c t l o c T n r r c p a s n i n n p r i n s p r t t h o h r r r c h

J P " " ' u l

hand le i n to t he dev i ce and , ho ld ing theb rush i n t he can , pump the hand le t o se ti t sp inn ing ( / e f f ) . Con t i nue un t i l t he re i sno longer any solvent f ly ing of f the brush.

STORING A BRUSH

Wrapping the bristlesA wel l-c leaned brush can be stored indef i -nitely. Wrap the bristles a few times in thick,absorbent paper. Avoid using plast ic wrap,which wi l l keep the br ist les from dryingproperly and may leave them l imp. Thepaper should cover the br ist les completely,extending beyond the t ips and over the fer-rule. Use a rubber band to hold the wrap-per in place, making sure the elast ic gr ipsthe ferrule rather than the bristles (rrehil.Hang the brush up to dry

Page 142: The Art of Woodworking - Wood Finishing

GLOSSARY

A-BAbrasive Either a coarse powder, ora piece of paper or fabric coated withgrit particles used to smooth woodin preparation for finishing or toabrade finish coats; includes sandpa-per, abrasive pads, steel wool, pumiceand rottenstone.

Aniline dye: A lightfast, permanentsynthetic dye derived from coal tars;soluble in water, alcohol or oil.

Artists' colors: Rich, colored pig-ments mixed in linseed oil: used totint paints and stains.

Base coat: An undercoat of glaze orpaint applied as the first step in manydecorative finishing techniques.

Bleach: A liquid that chemically alterswood; used to lighten the color.

Bleeding: The tendency of a stain orgrain filler to seep through to the top-coat. Best avoided by applying a washcoat on the stain or filler.

Brazilwood: A natural dyestuff extract-ed from the South American redwoodtree; used in chemical staining ofwood.

Bristle brush: A paintbrush with bris-tles made from the hair of animals,such as ox, badger, boar or sable.

Bronze powder: Metallic, powderedpigment used in stenciling or for oth-er decorative finishes, such as gilding.

Burnisher: A rodJike tool used tosharpen scrapers.

CCatalytic finish: A two-part finishcomprising resins and chemical cata-Iysts; the resins react with the catalyststo oxidize and harden the finish.

Crazing: The tendenry of a finish tofracture erratically as it dries; resultsfrom solvent incompatibility.

Curing: The process bywhich a finishhardens completely, leaving it readyfor rubbing out. Curing time variesaccording to the type of finish and thenumber of coats.

Cut The number of pounds of shellacflakes dissolved in eaih gallon ofdena-tured alcohol. A 3-pound-cut shellac,for example, contains 3 pounds ofshellac for every gallon ofalcohol.

D-EDistressing: A finishing techniquethat involves adding scratches, dentsand other blemishes to the wood ortopcoat to simulate the well-wornlook of an antique.

Driers: Chemicals added to a fin-ishing product to speed up thedrying time.

Dryingoil One of a group of organ-ic oils that harden when exposed tothe air; tung oil and boiledlinseed oilare examples.

Dyestuff: A natural coloring agentextracted from plants or animals andused as a base for dye stains.

F-GFisheye: The tendency of a finish toshow small circular depressions whencontaminated by silicone or wix.

Flat finish: A finish with no sheen:one that contains flattening agents,which reduce light reflection.

French polishing: A traditional fin-ish typicallybuilt up with manylayers ofshellac to produce a deep,lustrous sheen.

Gel stain: A blend of pigments anddyes in a gel that becomes liquidwhen stirred.

Glazs A heavy-bodied stain used indecorative finishes such as grainingand marbling.

Glossy finish: A finish with a reflec-tive, shiny surface.

Graining: A decorative finishing tech-nique in which a specific grain patternis replicated on a prepared surface.

H-r-J-K-LHeartwood: Wood from the center ofa log; generally darker than sapwood.

IfVLP: Abbreviation of high-volume,low-pressure; in finishing, a systemfor spraying that uses large volumesof air at low pressure to turn a liquidinto a fine mist.

fapan color: Highly refined coloredpigments; used to tint stains orprotective finishes such as Iacqueror shellac.

Lacquer: A tough, clear syntheticfinish usually derived from nitro-cellulose; dries quickly to a flat orglossy finish.

Lightfast Describes a stain or dyethat does not readily fade after pro-Ionged exposure to light.

Long-oil varnish: Varnish containing100 pounds ofresin for each 40 to 100gallons of oil, resulting in a productthat dries slowly to a durable and elas-tic finish. See short-oil varnish.

M-N-OMSDS: Abbreviation of manufac-turer's safety data sheet; the infor-mation describes the flammabiliryvolatility and health hazards ofafinishin! product.

Marbling: A decorative finishing tech-nique used to imitate the appearanceof marble.

Mineral spirits: A petroleum-basedsolvent commonly used for thinningvarious finishes and for cleaning appli-cation tools.

Mordant A chemical substance thatchanges the color ofwood; often usedin conjunction with natural dyes.

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NGR stain: Abbreviation of non-grain-raising stain; NGR stains aremade from aniline dyes in a waterlesssolution of methanol and oetroleumproducts; they are designed to avoidraising the grain of wood.

Orange peeh The tendency ofa top-coat to take on the texture ofanorange peel when the finish is sprayedpoorly or at the wrong viscosity.

Overspray: Dried finish particles thatadhere to the surface, or finish spraythat misses the workpiece and is dis-persed into the air.

P-QPadding: A technique for wiping ona finish with a cloth pad.

Photochemically reactive: Describesa finishing product that breaks downin its chemical structure whenexposed to light.

Pickled finish: An antique finish con-sisting of a light-colored glaze wipedover a basecoat.

Pigment Finely ground, colored par-ticles of earth or metallic oxides sus-pended in a liquid to create a stain ora tint for protective finishes.

Polymerized tung oil Tirng oil thathas been treated with heat to acceler-ate its drying time.

Polyurethane A synthetic, durable,oil-modified urethane varnish that isresistant to abrasion; available in lus-ters ranging from flat to glossy.

Pumice A volcanic rock that is groundto a powdery consistency for use asan abrasive.

RRaymarker: A tool used to producegrain patterns typical ofoak.

Reactive finish: A finish that hardenswhen exposed to the air; tung oil, var-nish and polnrrethane are examples.

Rottenstone: A fine abrasive madefrom pulverized limestone used torub out finishes to a high gloss; tex-ture is finer than that of pumice.

Rubbingoil A light oil used as alubricant when rubbing out finishes.

Rubbing out The process ofabradinga topcoat to level the surface and addsheen to the finish.

S-T-USanding sealer: A preliminary coatfor a lacquer finish.

Sap streak Pockets of pitch in woodthat tend to bleed into a finish unlessfirst sealed.

Sapwood: The live wood near theoutside of a log; generally lighter incolor than the interior. See heartwood.

Satin finish: A finish of intermedi-ate sheen; not as dull as a flat finish,nor as shiny or reflective as a high-gloss sheen.

Shellac A clear finish derived fromthe natural secretions of the lac beetle;sold ready to use or in flakes, whichare then mixed with denatured alcohol.

Short-oil varnish: Varnish containing100 pounds ofresin for each 5 to 12gallons of oil, resulting in a productthat dries to a hard, glossy finish. Seelong-oil varnish.

Smoothing plane: For shaving woodsurfaces smooth and level; longer thanthe average jack plane.

Solvent-release finish: A finish thatforms a solid film after the solventhas evaporated; shellac and lacquerare examples.

Solvent A liquid used to dissolveanother substance; examples areturpentine, mineral spirits, toluene,acetone and water.

Stain: A finishing product used tocolor wood; may contain dyes, pig-ments or chemicals.

Thck cloth: A cloth dampened withan oil-and-varnish mixture or withwater; used to remove sanding parti-cles from wood surfaces.

Tlrnnic acid: A naturally occurringacid found in wood; changes colorwhen exposed to certain chemicals.

Thinner: A solvent used to reducethe consistenry of a finish.

Topcoat The final finishing productapplied to the workpiece.

Tung oil A water-resistant drying oilderived from the seeds of the Chinesetung tree; available in pure, modifiedand polymerized forms. Also knownas China wood oil.

Universal color: Concentrated pig-ments used to tint protective finishes,such as varnish or lacquer.

V-W.X-Y-ZVarnish: A clear finish made withsynthetic oils that excels at resistingwater and alchohol.

VOC rating: Indicates the amount ofhazardous organic solvents in a finish;provided in percent, grams per liter orpounds per gallon.

Wash coat A coat of diluted finishingmaterial for sealing wood pores.

Water-based finish: A product inwhich the solvent is primarily water.

Wipingstain: A non-fading staincontaining pigments suspended in oil.

Wood filler: A putty product used forrepairing surface damage in wood, ora paste used for filling open grain.

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Page 144: The Art of Woodworking - Wood Finishing

INDEX

Page references in iralics indicatean illustration of subiect matter.Page references in bold indicatea Build It Yourself project.

AAbrasives, 35, 37, 128

Abrasive cord,40Making a sandpaper cutting board

(Shop Tip), 37Rottenstone, 127, 130, 1 3 1- 1 32Shop-made abrasive tape (Shop Tip), 40See also Pumice

Ammonia,80-81Antique effect finishes, 55

Pickling, T5

BBelt sanders, 23, 35Blades. See Cabinet scrapers; Hand

scrapers; PlanesBleaching, 57-58BIockpIanes, 22, 29Bronze powder stenciling, 113, 117Broue de noix. 69Brushes, fr o nt en dp ap er, 83

A foam brush (Shop Tip),92Buffing, 126,128,135

Keeping a buffing bonnet grit-free(Shop Tip), 133

Build It Yourself:Graining

block cushion grainers, l2lProtective finishes

spray room dollies, 98turntables for spraying, 100

Surface preparationcontoured sanding block, 39

Burn-in kits,43,46

CCabinet scrapers, 22, 30, 34

Sharpening, 30-32using a file clamp (Shop Tip), 3lusing a variable burnisher

(Shop Tip), 33Using old scraper blades to cut half-

blind dovetails (ShopTip), 34Chemicals:

Ammonia.80-81BIeach. 57-58Mordants, T6-79Spills, l6See also Solvents: Stains

China wood oi1,86,87Cleaning techniques, 1 36- I 39

Chemical spills, 16Finished surfaces, 134

Decorative painting, I I ITools. l.l2See also Graining; Marbling;

Stenciling

DDents:

Repair,44Dollies,98Dovetail ioints:

Using old scraper blades to cut half-blind dovetails (ShopTip), 34

Drfrng oils, 87, 134Preventing reactive finishes from

drying out (Shop Tip),87Dyes, 5t 59,60-63,70

Natural dyes,69,76-79See a/so Stains

E-FEbonizing, 55

A chemical stain for ebonizing(Shop Tip), 79

File clamps, 3-lFinishes. See Decorative painting;

Polishing; Protective finishes; StainsFire:

Extinguishers, 12, 17Safety precautions, 12, 1 7Spray rooms, 103

French polishing, 106- 109Making a pumice dispenser

(Shop Tip), 107Fuming,80-81

GGel stains, 65, 66-67,70Glazing stains, 65, 66- 67, 7 0Grain:

Raising,21, 50Grain filler, 21, 51-53

Coloring grain filler (Shop Tip), 50Lightening wood with grain filler

(Shop Tip), 58Graining, lll, 118-120

Tools,112,l2l

HHalf-blind dovetail ioints:

Using old scrapei blades to cut half-blind dovetails (Shop Tip),34

Hand scrapers, 21,22, j0, jjSharpening, j0-j2

using a file clamp (Shop Tip), 3lusing a variable burnisher

(Shop Tip), 33Using old scraper blades to cut half-

blind dovetails (ShopTip), 34High-volume, low-pressure spray

systems, 93, 94Holes:

Fillingfilling a damaged corner

(Shop Tip), 49Patching,4T-49

HVLP spray systems, 93, 94

I-I-KInsurance:

Spray rooms, 103lapan colors, 65, 66- 67, 70.,lgs:

Block cushion grainers, l2lSupports for drying (Shop Tip), 74Turntables for spraying, 100Variable burnishers (Shop Tip), 33

L-M-NLacquers, 90,134Liming,75Linseed oil, 9, 87Marbling, 110, 122-125

Tools, l12McGoldrick, Pari,6-7Metric measures:

Conversion, back endpaperMordants, T6-79Moser, Thomas, 8-9Natural dyes,76-79NGR stains, 60, 6l

O-P-QPaddinglacquers, I06Palm sanders, 23, 35Paste wood filler. See Grain fillerPatching compounds, 43, 45-46

Filling a damaged corner(Shop Tip), ae

Using a glue gun to apply shellacstick (Shop Tip), a6

Pickling,75Pigment stains, 55, 59,64-67,70

See also StainsPlanes, 20,2I,22,24

Adjustment, 27-28Sharpening, 24,25-27

Planing, 21,28-29Polishing:

Waxing, 127,135See also Buffing; Rubbing out

Polyurethanes, 88Pore filler. See Grain fillerPower tools. See Sanders; SprayersProductlabels, l8Protective clothing, 12Protective finishes, 83, 86, 87-90

Application techniques, 83, 86brushing,83, 92flooding, 83French polishing, 106- 109padding, 9lspraying, 82, 83, 97- 101, I0Ospraying problems, 104- 105wiping,83, 9l

Cwing, 129

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Tools. 85a foam brush (Shop Tip),92sprayers, 84, 85,93-96, 101viscosity cttps,89,96

Tlpes{rfrng oils, 87,134lacquers, 90,134polyurethanes, 88shellacs, 89, 10G109, 134varnishes, 83, 88, 134

See also Buffing; Rubbing out; WaxingPumice, 130, 131-132

French polishing, 107- 108Making a pumice dispenser

(Shop Tip), l0Z

RRaising the grain,2l, 50Random-orbit sanders. 38Reactive finishes. 87

Preventing reactive finishes fromdrying out (Shop Tip), 87

Repairs:Finished surfaces. 134Surface pr ep ar ation, 4 3- 49

gluing an edge splinter back(Shop Tip), aa

Respirators, 12,14-15Storing respirator cartridges

(Shop Tip), .15Rottenstone, 127, 130, I 3 1- 1 32Rubbing compounds, J33Rubbing ofi, 126-133

Tools, 128

SSafety precautions, 12-13

Bleach. 57Dual-cartridge respirators, 12, 14- 15

storing respirator cartridges(Shop Tip), 15

Fire, 12, 17,103Mordants, 77Protective clothing, I2Spray booths, .13, 84Spray rooms, 102- 103

Sanders, 23,35,38Buffing bonnets, 126, 128, 133

keeping a bufEng bonnet grit-free(Shop Tip), 133

See also AbrasivesSanding, 35-36

Curved surfaces, 3& 40Finding flaws (Shop Tifl, alRemoving dust particles, 42

making a tack cloth (Shop Tip), 42Tight spots, 4lSee also Sanders

Sanding blocks:Contoured sanding blocks, 39Curved surfaces, 38Shop-made sanding blocks

(Shop Tip), 36Sandpaper. See AbrasivesSavoy, Prew, l0-lJScrapers. See Cabinet scrapers;

Hand scrapersScraping,33-34Scratches:

Repair, 134Shellacs, 89,134

French polishing, 106- 109making a pumice dispenser

(Shop Tip), l0ZShellac sticks, 43, 45-46

using a glue gun to apply shellacstick (Shop Tip),46

Shop Tips:Decorative finishes, 114, 115Protective finishes, 87,92, 107Rubbing out, 133Safety, l5Staining, 58, 69, 71, 73, 24, 79Surface preparation

grain filler, 50repairs, 44,46,49sanding, 36, 37, 40, 41, 42scraping, 31,33, 34

Smoke detectors. 17Solvents:

Product labels. 18Protective finishes, 86, 103Safety precautions, 12- 19, 84, 102- 103Toxicity, 19,86, 103Waste disposal, 12, 13, 16

Sprayers, 84, 85,93-96Cleaning, 10.1Viscosity cups, 89,96

Spraying, 97,99, 101Dollies,98Problems, 104-105Spraybooths, 13,84Spray rooms, 102- 103Turntables, 100

Staining, 54,55,71-74Controlling the flow of stain

(Shop Tip), 7lEnd grain, 69Getting stain into tight spots

(Shop Tip), 73Pickling,75Supports for drying (Shop Tip), 24Tools. 56See also Bleaching; Fuming

Stains:ChemicaI, T6-79

a chemical stain for ebonizins(Shop Tip), 79

Dyes, 5t 59,60-63,70natural dyes,69,76-79

Pigment stains, 55, 59,64-67,70Preparation, 68

preparing a natural walnut stain(Shop Tip), 6e

See also StainingStenciling, 1 1 1, 1 I 3- I 16

A cure for bleeding (Shop Tip), l15Bronze powder, 113, 117Patterns, back endpaper, I 13- 1 14

projecting a pattern (Shop Tip), 114Tools, I 12

Surface preparation, 2 IRepairs,43-49

filling a damaged corner(Shop Tip), 49

gluing an edge splinter back(Shop Tip), 44

See also Planing; Sanding; Scraping

TTack cloths:

making a tack cloth (Shop Tip), 42Tools:

Decorative painting, 1 I 2Protective finishes, 84-85, 92Rubbing out, 128Spraybooths, 13,84Spray rooms, 102- 103Staining, 56Storage, 136, 137, 139Surface pr ep ar ation, 2 2- 2 3Variable burnishers, 33See also Abrasives; Brushes; Cabinet

scrapers; Hand scrapers; Planes;Sanders; Sanding blocks; Sprayers

Tung oil, 86, 87

u-v-w-x-Y-zU.S. measures:

Conversion, back endpaperVapor pressure, 18Variable burnishers, 33Varnishes, 83,88,134VOC (Volatile Organic Compound)

rating, 18Walnut oil, 87Walnut stains:

preparing a natural walnut stain(Shop Tip), 6e

Wash coats,2 l ,5 l ,53Waste disnosal:

Solvenis, 12,13, 16Waxing, I27, 135Wax sticks, 43Wiping stains, 64-65 70Wood:

Color,55Grain.5l

Wood filler,43, 45Filling a damaged corner (Shop Tip), 49

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ACKNOWLEDGMENTS

The editors wish to thank the following

SAFETYDeVilbiss Spray Booth Products Co., Barrie, Ont;

Chris A. Minick. Stillwater, MN

PREPARING THE SURFACEAdjustable Clamp Co., Chicago, IL; American Tool Cos.,

Lincoln, NE; Black and Decker/Elu Power Tools, Hunt Valley, MD;Delta International Machinery/Porter Cable, Guelph, Ont.;

Hitachi Power Tools U.S.A. Ltd., Norcross, GA;Lee ValleyTools Ltd., Ottawa, Ont.; Record Tools Inc, Pickering, Ont.;

Stanley Tools, Division of the Stanley Works, New Britain, CT;3M Canada, Dorval, Que.; Veritas Tools Inc., Ottawa,

Ont./Ogdensburg, NY

CHANGING THE COLORAdjustable Clamp Co., Chicago, IL; Jonathan B.Kemp, H. Behlen Co.,

Amsterdam, N.Y.; Olde Mill Cabinet Shoppe, York, PA;Wagner Spray Tech Corp., Minneapolis, MN

DECORATIVE FINISHESAdvanced Equipment Manufacturing Company, Inc., Chicago, IL;

Lee Valley Tools Ltd., Ottawa, Ont.

PROTECTIVE FINISHESDeVilbiss Ransburg Industrial Coating Equipment, Barrie, Ont.;

DeVilbiss Spray Booth Products Co., Barrie, Ont.;The Hydrocote Co. Inc., East Brunswick, NJ;Wagner Spray Tech Corp., Minneapolis, MN

FINISHINGTOUCHESDelta International Machinery/Porter Cable, Guelph, Ont.;

H. Behlen Co., Amsterdam N.Y.;3M Canada Inc.,Dorval, Que.

CLEANINGAND STORAGELee Valley Tools Ltd., Ottawa, Ont.

Chris A. Minick, Stillwater, MN

The following persons also assisted in the preparationof this book:

Elizabeth Cameron, Donna Curtis, Lorraine Dor6,Kent J. Farrell, Kam Ghaffari, Michel Gigudre,Serge Guibord, Brian Parsons, Maryo Proulx

PICTURE CREDITS

Cover Paul McCarthy/Au Puits de Lumidre6,7 Ronald Maisonneuve

8,9 Grace Huang10,11 Ian Gittler

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IIIIIIIIIIItIIIIIIItIItIttIIIII!

U.9, AND METRICCONVERSIONTo find the metric meaeureequivalent of a U.9. measure tnthe left-hand column, multiplyby the converaion facf,or tn f,hecenter column. To find the U.9.meaaure equivalenL of a metricmeaeure in the riqht-hand column,divide by Lhe converaion factor.

CONVERSION FACTOR

0.454

28.350

3.785

3.785

3.785

0.946

0.946

0.473

0.236

29.573

METRIC MEASURE

Kilogram

Gram

Liter

Liter

Liter

Liter

Liter

Liter

Liter

M i l l i l i t e r

WORKSHOP GUIDE

U.S. MEASURE

Weight

Pound

Ou nce

Volume (Liquid)

Gal lon 4 Quarts

16 P in ts

128 F lu idounces

Quart 2 Pints

32 F lu idounces

Pin t 16 F lu idounces

Hal f p in t 8 F lu idounces

Flu idou nce

STENCIT PATTERN

Thte fruit -bowl pa|Lern waea commonly uaed mol)f on19th Century furniture, Tomake a etenctl from iL todecorate your own furnt-i l r r e f n l l n t t , f . h e a l e n a

6tartinq on pa4e 113.

N o o o o o 0\.rN0%

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