THE GASKET FABRICATORPAGE 2 THE GASKET FABRICATOR DECEMBER 2007 NEW ASSOCIATION MEMBERS Fabricators...

THE GASKET FABRICATORDECEMBER 2007

Volume 26 Number 3 DECEMBER 2007

THE GASKETFABRICATOR www.gasketfab.com

In This Issue President’s MessageGary FellGary FellGary FellGary FellGary Fell

President’s MessagePages 1-2

New AssociationMembersPage 2

Future MeetingSchedulePage 2

Company ProfilesPage 3

AdvertisementsPages 4, 12 & 15-16

Press ReleasesPage 5

Member Presentations atFall MeetingPages 6-7

Benchmarking ReportPage 7

Fall 2007Meeting Pictures

Pages 8-9

Baggy Webs: MakingMeasurement andMitigation Thereof

Pages 10-11

Technical ArticlesPages 13-14

Continued on Page 2...

As we prepare for the Holiday Season and complete thebusiness plan for 2008, don’t forget to reserve yourtabletop for the 2008 Gasketing/Converting Expo. It is asimple process that can be done online by accessing theGFA website at gasketfab.com. The program is progressingvery well. By the time of the fall meeting in Monterey,approximately 50% of the tables had already been reserved.There will be two sessions where you can get valuableinformation on slitting and laminating and a technicalsession on adhesives followed by the expo.

This year, ISD and IADD are co-sponsoring the eventwith GFA. With the addition of IADD this year, we anticipate a larger turnout thanwe had in 2006. So plan now to join us in Orlando on April 1, 2008. If you arelocated anywhere in the northern section of the United States, you will be readyto leave the gray, overcast, snowy weather for warm sunshine by April and whatbetter than a GFA meeting in Orlando to lift your spirits. Spend time with currentfriends discussing events since Monterey, and add new friends from the GFA,IADD, and ISD.

We had another first in Monterey. Ken Stober lead a breakfast discussionon surviving without globalization. Members discussed the impact globalization ishaving or has had on their businesses. The changes in the market as a result ofglobalization and what we need to do to compete. Since that meeting, a subcommitteefrom Programs and Locations has been working to develop a list of topics thatwould interest our members. If you have suggestions, please send an e-mail withthe information to Bob or Pete and they will send it to the committee. We continuallylook for new ways to add benefit to your GFA membership. I think it is working;we have 72 fabricator members and 53 associate members, which is the largestmembership since I have been attending GFA meetings.

I mentioned this in Monterey, but I want to acknowledge the work of twoGFA members retiring in 2007. First is Paul Yager, whom I had the pleasure ofworking with on the Communications Committee. Paul was a member of the Boardof Directors for a number of years. He was responsible for the technical articlesthat are published in the newsletter; starting with clippings that he personallyresearched for each newsletter before suggesting that we have someone writetechnical articles for the newsletter that would focus on subjects of interest to ourmembers. I want to wish Paul and Marion a long and happy retirement.

Next is Ron Kelling. I was the treasurer when Ron was President andremember the conference calls with the Executive Committee to review the budgetfor the upcoming year when we would question the projected income because we

DECEMBER 2007THE GASKET FABRICATOR

NEW ASSOCIATIONNEW ASSOCIATIONNEW ASSOCIATIONNEW ASSOCIATIONNEW ASSOCIATIONMEMBERSMEMBERSMEMBERSMEMBERSMEMBERS

FabricatorsGasko and Rhopac Fabricated Products

Medina, OHwww.gasko.com / www.rhopac.com

Glassfiber del Norte SA de CVMonterrey, NL Mexico

www.glassfiber.com

SuppliersFrenzelit Sealing Systems

New Berlin, WIwww.frenzelitsealing.com

Hudson Industrial Cutting SlutionsHaverhill, MA

www.hudsoncutting.com

Larson WorldwideNorwell, MA

www.larsonworldwide.com

PRESIDENT'S MESSAGEPRESIDENT'S MESSAGEPRESIDENT'S MESSAGEPRESIDENT'S MESSAGEPRESIDENT'S MESSAGEContinued from page 1...

Visit us online at:www.gasketfab.com

weren’t always sure how many members we would havenext year. I found out in Albuquerque that Ron and I havethe same feelings when it comes to dessert; it is notsomething I plan to share so if you would like some, orderyour own!! Ron dedicated considerable time to growingand improving the GFA. I want to wish him and Diane anenjoyable retirement.

I can’t close this letter without reminding you toget involved. Review the list of committees and chooseone that holds your interest. Go to the meetings and takean active role in that committee’s business. You will meetsome great people, you will have fun, and you will have thesatisfaction that as the organization continues to grow, thatyou had a part in making it happen. You will find that itwon’t take that much time away from golf or other socialactivities that you planned for the meeting. You willprobably meet someone that shares your interest andwould enjoy participating in those same activities with you.

Have a Happy Holiday and a Happy and HealthyNew Year. I look forward to our next meeting, April 1-3,2008, in Orlando, Florida.

NEWSLETTER

The Gasket Fabricator is published by the Gasket FabricatorsAssociation and distributed to all members and prospectivemembers of GFA.

President ................................................................Gary FellVice President ...............................................................Clem FoleyExecutive Director................................................. Robert H. EckerAdministrative Director/Newsletter Editor................. Peter LanceCommunications Committee Chair.....................Chris Brand

Members are encouraged to contribute articles and items ofinterest to the Gasket Fabricator. All contributions shouldbe addressed to: Executive Director, GFA, 994 Old Eagle SchoolRoad, Suite 1019, Wayne, PA 19087-1866, Phone (610) 971-4850, Fax (610) 971-4859, Home Page: www.gasketfab.com,E-mail: [email protected].

Articles appearing in this publication may not be reproducedwithout written consent from the Association. Articlesappearing in the Gasket Fabricator are the views of theauthors and not necessarily those of the Association.

© Copyright 2007 Gasket Fabricators Association

Gasketing/Converting Expo ’08April 1-3, 2008Caribe RoyaleOrlando, FL

Fall 2008 Semi-Annual MeetingSeptember 23-25, 2008

Loews Ventana Canyon ResortTucson, AZ

GFA FUTURE MEETINGGFA FUTURE MEETINGGFA FUTURE MEETINGGFA FUTURE MEETINGGFA FUTURE MEETINGSCHEDULESCHEDULESCHEDULESCHEDULESCHEDULE


COMPANY PROFILESCOMPANY PROFILESCOMPANY PROFILESCOMPANY PROFILESCOMPANY PROFILES

Hudson Industrial Cutting Solutions, is focused onproviding you, the customer, with the information that willallow you to choose the most suitable equipment andmethods to accomplish your specific cutting requirementsWhilst continuing to offer our own legendary Samcorange of machines, we are not locked into any onemachine provider and also offer quality machines fromAtom, Allevi (MAV) Sysco, Elitron and Zipor. So whetheryou need a clicker, traveling head, beam press, or a fullblown automated system with single or synchronous niprolls, or gripper feeds, large and small table cutters, witha simple drag knife, or oscillating knife, or milling capabilities,or a water jet system, using plain water or abrasives, weare at your service.

We offer nationwide coverage and have salesoffices in MA, OH, IL, MI, PA, and NC along withadditional representatives throughout the USA andCanada. Our parent company, USM Corporation, datesback to the 1890’s and after many acquisitions anditerations we have established a knowledge base and

team of experts second to none. The gasket industry haslong been, and continues to be, a market sector we havesuccessfully supported, with many innovative ideas andtechniques, to improve productivity and material utilization.Our new line of High Speed Cutters, along with our othervast range of machinery including the latest in die-lesscutting systems, make us your obvious choice supplier.

We can also offer you Simona LongLife® cuttingpads. These pads are competitively priced and are madein Germany, using the most up to date equipment available,by the same company that makes Fryslen pads.

Please don’t hesitate to give us a call at any of ouroffices listed below, or go to our website athudsonmachinery.com where you can find additionalinformation.

Alan Clark, Marketing Director32 Stevens Street, Haverhill, MA [email protected]: 978-556-7107 ; Fax: 978-373-7295

David Lees, Senior V.P.984 Anderson Glen Drive, Cincinnati, OH [email protected] Tel: 513-324-4243; Fax: 513-474-0949

Peter Quinlan, Cutting Consultant116 Villa Lake Drive, Fort Mill, SC [email protected]: 716-310-5054

Rick Villa, Cutting Consultant656 Breconshire Drive, Saline, MI [email protected]: 734-476-705; Fax: 734-429-2064

Jeff Mayotte, Cutting Consultant32 Stevens Street, Haverhill, MA [email protected]: 978-556-7163; Fax: 978-373-7295

USM Canada Ltd.Mr. Frank Rossi8810, Place Ray-Lawson, Anjou (Quebec)Canada, H1J [email protected]: 514-355-3690; Fax: 514-355-5953

GLASSFIBER DEL NORTESA DE CV

Founded in 1991, Glassfiber has its headquartersin Monterrey, NL Mexico, with stocking warehouses andoffices in Mexico City, Guadalajara, Cd. Juarez, Chihuahuaand Cancun. Initially, Glassfiber serviced only the HVACindustry and in 1997 started its manufacturing processes toservice the OEM and specialty customers.

Presently, Glassfiber has a diverse fabricationshop to service customers with their specific requirementsin the utilization of foam and fiber materials as specified ineach application in the OEM, Building, Appliance andAutomotive industry.

With our ISO-9001-2000 certification, ourorganization has continually improved over the years toachieve high levels of service, customer satisfaction, andquality that distinguish our organization from competition.The essence of Glassfiber del Norte is: commitment,service and quality.

For more information, visit www.glassfiber.com.


PRESS RELEASESPRESS RELEASESPRESS RELEASESPRESS RELEASESPRESS RELEASESFREUDENBERG-NOK GENERAL

PARTNERSHIP ACQUIREDTHE ASSETS OF

PRECISION INDUSTRIESCORPORATION

Freudenberg-NOK General Partnershipacquired the assets of Precision Industries Corporationof Germantown, WI, a developer and manufacturer ofspecialized custom diaphragms. This acquisition providesFreudenberg-NOK with fabric reinforced diaphragmcapabilities in North America, as well as on a globalbasis with its partners in Europe and Japan.

Precision Industries Corp. was established in1986 as a manufacturer of high quality diaphragms,specializing in fabric-reinforced diaphragms for smallengines, fuel systems, irrigation, gaseous fuels, pneumaticcontrols and medical regulators.

John Plant, owner and president, establishedPrecision Industries as a strong and focused supplier ofspecialty diaphragm products for general industrymarkets. Plant will continue with Freudenberg-NOKthrough a transition period. Eric Weber, currently vicepresident of operations, sales and marketing, will managethe operations at the Germantown facility forFreudenberg-NOK.

"Freudenberg-NOK has a goal to grow in thespecialty diaphragm market and this acquisition reflectsour commitment to that vision," said Dr. Jorg Schneewind,general manager of the Special Sealing Products Division.


VENTURE TAPE ADDS NEWPRODUCTS

TO VENTURECLAD“ F AMILYVenture Tape has introduced two new products

to its highly successful VentureClad™ product line.VentureClad™1577CW®T is a zero

permeability, white Tedlar® faced jacketing made withtwo layers of aluminum foil, a layer of polyester film andan outer layer of Tedlar coated with a special coldweather acrylic adhesive system. Tedlar® is a chemicallyinert, lightweight, impervious film that has distinctivemechanical, electrical and chemical properties. Pairedwith Venture Tape’s CW®, a unique cold weatheracrylic adhesive system, the new product offers the keybenefits of zero permeability moisture resistance andsuperior performance in harsh environments.VentureClad™1577CW®T is FDA approved and isrecommended for interior use in food processing plants

VENTURE TAPE NOW OFFERSCOLD WEATHER ACRYLIC

TAPE IN BLACKVenture Tape Corp. has added Venture Tape

1538CW® in black to its extensive line of facing tapes. Atri-directionally reinforced black polypropylene scrim/kraftlamination, 1538 is coated with Venture Tape’s specialcold weather (CW®) acrylic pressure sensitive adhesivesystem, which makes it ideal for use in cold weatherapplications, combining quick stick at normal temperatureswith superior low temperature performance down to 10ºF. The new cold weather tape also offers exceptionalperformance in humid and hot conditions. Venture Tape1538CW® is primarily used as a closure system and vaporseal on Lamtec WMP-DW faced thermal insulation.

“Venture Tape’s acrylic adhesives are uniformlymanufactured with a specially developed formulation thatcombines high shear strength with both high tack and coldstick properties, which is critical in working under less-than-ideal weather conditions,” says Ed Sore, productmanager for Venture Tape. “The bond strength of theproducts in this aggressive, high temperature adhesivefamily actually increases after application because of theproduct’s self cross-linking acrylic polymers.”

Venture Tape 1538CW® comes in standardwidths of three inches (7.6 cm) and standard lengths of 50yards (46m), and is also available in grey and white.

For samples or more information about theseproducts, contact Ed Soreat at 800 343-1076 (U.S.); 800544-1024 (Canada), or visit wwwventuretape.com.

on piping and ducts. It is resistant to most chemicals usedin plant wash downs, and because of Tedlar®’s resistanceto salt, it is ideal for use on piping near bridges and piers.

VentureClad™1577CW®BE Black Embossedis an embossed, five-ply laminate made with three layersof aluminum foil and two layers of polyester film coatedwith Venture Tape’s CW® special cold weather acrylicadhesive system. It combines superior quick stick atnormal temperatures with superior low temperatureperformance below freezing. It is highly puncture and tearresistant as well as flame retardant.VentureClad™1577CW®BE is primarily used as a zeropermeability facing for insulation. It is also used as a lowtemperature vapor barrier joint closure system. Itsemissivity of .70 is important in the design of some coldtemperature insulation systems. UL listed, it offers all ofthe benefits of embossed VentureClad™ in the colorblack and is ideal for indoor and outdoor applications.


MEMBER PRESENTATION SUMMARIESMEMBER PRESENTATION SUMMARIESMEMBER PRESENTATION SUMMARIESMEMBER PRESENTATION SUMMARIESMEMBER PRESENTATION SUMMARIESBelow are summaries of presentations given by GFA Members at the Fall Meeting in Monterey, California.

ADCHEM CORPORATIONPamela Fardelos, National Sales Manager for the

Adchem Corporation presented a brief history of the 42-year old company and an overview of its core capabilities:Adchem, an ISO 9001 certified and A2LA accreditedcompany, manufactures an innovative line of pressure-sensitive adhesive tape systems, including double-coatedpapers, films, tissues, foams and fabrics; transfer tapes;one-side coated products and other custom-coated specialtyproducts. The company's 100% solids adhesives, solventand water based acrylics and rubber adhesives are usedin a variety of industries, including automotive, construction,electronics, graphic arts, medical and general industrialtape applications.

In addition, 3 new series of products wereintroduced, each with uniquely formulated adhesivesystems. The 7830 Series is currently comprised of 3- and4- mil acrylic transfer adhesives featuring excellent foamto foam bonding properties; good adhesion to many lowsurface energies; and excellent peel and shear propertiesat high temperatures. This was followed by a review of7854, a new 4-mil acrylic transfer adhesive which wasspecifically designed to bond to TPOs, but alsodemonstrates excellent bonding properties to powdercoated metal surfaces. It also meets several automotivespecifications. Finally, the 7740 Series, which is are ultrahigh performing 2- and 5-mil acrylic adhesive systemswith fiber-filled reinforcement. These products haveexceptional shear and peel performance at very hightemperatures and are specifically designed to bond to lowsurface energy substrates.

Adchem continually formulates new adhesivesystems to ensure that the fabricator market has optimizedsystems to bond to the ever increasing new materials onthe market.

PRECO, INC.One of the greatest challenges for Gasket and

general Converters, in order to compete both regionallyand globally, is to reduce costs and maintain, indeed,increase margins/profits. While fixed costs and materialcosts/yields are important, a greater emphasis needs to beplaced with our engineering and production people to findways to A) reduce labor costs, and B) offer additionalfeatures, or presentations of parts without increasingcosts. In other words, adding tangible value.

Preco has now added a Servo - driven RotaryConverting Platform, which is extremely flexible, forprocessing materials at speeds of up to 300 ft/minute. Thisplatform is of a backplane design so that components, suchas Rotary diecutting, laminating, inkjet printing, embossing,and laser cutting, can be run in correct registration to eachother, in One process, using One operator/technician.Speeds of Rotary processing will reduce "Labor as aPercentage of Sales" dramatically, and will be evident onthe "bottom line" in short order.Preco is conducting site demonstrations now.

ZOTEFOAMS, INC.ZOTEFOAMS HIGH PERFORMANCE FOAMS

ZOTEFOAMS products are made by a uniquehigh pressure nitrogen gas solution process. The superiorityof these products, stems directly from the use of this highpressure gas technology. This produces a pure,chemically inert foam without blowing agent residues andwith a uniform cell structure and regular cell walls. Theprocess comprises three main stages:

(a) High quality extrusions and cross-linking of solidpolymeric sheet.

(b) Impregnation of solid sheet with pure nitrogen gasat elevated temperature and extremely high pressure.

(c) Final expansion of the impregnated solid sheet inthe low pressureautoclave.

The key characteristics of ZOTEFOAMSproducts are:(1) Pure - Nitrogen is the only blowing agent.(2) Durable - Cross-linking improves physical

properties and temperature stability.(3) Low Odor - Nitrogen has no odor.(4) High Quality - Density variation across the sheet

is minimal due to free expansion.

ZOTEFOAMS products consist of AZOTETechnical Products and ZOTEK High PerformanceProducts

Presentation Summaries continued on Page 7...


COMPAC CORPORATIONCompac was founded in 1968 and was acquired

by the TriMas family of companies in 1991. Relying on itscore capabilities of coating and laminating of flexiblesubstrates, Compac places its highest priority on providingsolutions that meet the demanding needs of our customers.

Located in a new 182,000 square footmanufacturing facility in Hackettstown, New Jersey,Compac is ISO 9001 certified and has warehouseslocated throughout the United States to serve its broadnetwork of customers.

Compac’s products serve four primarymarketplaces:

Construction—Compac produces a complete lineof pressure sensitive insulation tapes and a broad line ofvapor retarder facings for insulation applications onconstruction projects, metal building, heat reflecting andair-handling systems.

Industrial—Compac produces pressure sensitiveadhesive tapes including foil, double coated, transfer andfabricating tapes for bonding and laminating numeroussurfaces including paper, metals, wood plastics and foams.

Automotive—Compac produces bonding andlaminating tapes designed to adhere to numerous foamsubstrates including Ethers, Esters, Polyethylene,Neoprene and Vinvl. These tapes are typically usedproduce gaskets used in the automotive industry as wellas noise and vibration attenuation applications.

Electronics—Compac’s products typically areused as aids in the assembly of electrical components,printed circuit board fabrication and EMI/RFI shielding.

As part of its development efforts, Compac hastwo new adhesive tapes to its NetBond™ family ofFabricator Tapes.

NetBond™ 5 --a high performance fabricatingtape offered at attractive pricing levels versus our standardNetBond™ 10.

NetBond™ 50 a high performance, 5 Mil scrimreinforced laminating tape that has improved gap fillingproperties and higher levels of adhesion.

Compac is eager to develop a partnership withyou in an effort to develop solutions tailored to yourspecific application needs.To learn more about Compacand its line of Industrial and fabricator tapes please visitour web site at www.compaccorp.com.

MEMBER PRESENTATIONMEMBER PRESENTATIONMEMBER PRESENTATIONMEMBER PRESENTATIONMEMBER PRESENTATIONSUMMARIESSUMMARIESSUMMARIESSUMMARIESSUMMARIESContinued from page 6...

BENCHMARKING REPORT

Below are the results from the BenchmarkingSurvey, which was undertaken to give GFA membersa thumbnail sketch of how other members are fairingat this time.

We had 29 out of 72 Fabricator responses.

1. Most Recent Quarter Sales Compared toPrevious Quarter

UP DOWN SAME14 9 648% 31% 21%

2. Current Quarter Sales ProjectionCompared to Last Quarter

UP DOWN SAME16 8 555% 28% 17%

We had 25 out of 53 Supplier responses.

1. Most Recent Quarter Sales Compared toPrevious Quarter

UP DOWN SAME14 8 356% 32% 12%

2. Current Quarter Sales ProjectionCompared to Last Quarter

UP DOWN SAME14 4 756% 16% 28%



FALL 2007 MEETINGPORTOLA PLAZA HOTEL, MONTEREY, CALIFORNIA

First Time Attendees (left to right):Steve Reidenbach, Compac Corporation;Scott Lindberg, Syntac Coated Products;

Steve Ubelhoer, Rogers Corporation; and Eric Stevenson, Avery Dennison

First Time Attendees (left to right):Bill Bates, Avery Dennison;

Joanna Vos, Amorim Industrial Solutions;Ruben Elizondo, Glassfiber;

and Gerardo Vazquez, Glassfiber

Gary Fell,President of the GFA,

at the Semi-Annual Dinner

Lauron Sonnier with SonnierMarketing & Communications

at the General Session

Tom Paradzinski with PDF,Inc. at the General Session

Doug Ginter withE.G. Gasket & Supply Inc.

at the General Session

Esperanza del Valle - Mexican Folkloric DanceCompany at the Semi-Annual Dinner


SUPPLIER EXPO


BAGGY WEBS: MAKING MEASUREMENTBAGGY WEBS: MAKING MEASUREMENTBAGGY WEBS: MAKING MEASUREMENTBAGGY WEBS: MAKING MEASUREMENTBAGGY WEBS: MAKING MEASUREMENTAND MITIGATION THEREOFAND MITIGATION THEREOFAND MITIGATION THEREOFAND MITIGATION THEREOFAND MITIGATION THEREOF

By: Dr. David R. Roisum, Finishing Technologies, Inc.The following is part one of a two-part article.

Part two will appear in the March 2008 issue.Web bagginess is a defect so tenacious that few

machines will totally escape its grip. It can be found on webformers, calenders, coaters, printers, weaving machines,winders and so on. It is so pervasive that it can be foundon materials as diverse as tissue, writing paper, carpet,nonwovens, plastic film and steel strip.

While it is expected that defects share similarphysics across dissimilar grades, it is very unusual for adefect to have such a range as does bagginess. Thus, eventhough the defect may not be the number one cause ofwaste on a particular machine, its total cost to the webindustry could be quite large. Web bagginess is sochameleon-like in its appearance that it is given manyaliases such as baggy lanes, camber, frogbellies, layflat,puckers and many more. This coupled with its appearanceon such a wide variety of webs and processes lends peopleto believe that their situation or defect is unique, eventhough there is clearly an underlying commonality as wewill see.

If this were not enough, bagginess is difficult tomeasure. While the industry has many instruments andmeasurements to choose from, the common ones do notcorrelate well to bagginess because they do not measureanything closely related to it. While there are ways tomeasure bagginess more directly, most are tedious orfraught with uncertainty or both. This means that cullingand rejection is typically done by subjective visualappearance. This means it is difficult to research processconnections and to measure progress as there are fewgood measurements of this vital quality parameter.

Finally, there are so many different root causes ofbagginess. In one case, a baggy lane could be causedby a tiny imperfection in a die lip, while in another it mightbe due to a local hot spot in an oven. It could be caused bya nonuniform calender nip, a misaligned roller, a spreaderor a slitter. It is not unusual to have several areas ofbagginess side-by-side on the same web, yet each have adifferent root cause. For these reasons and others, bagginesscan be a very difficult problem to diagnose. Few can takea specific baggy lane and point to the portion of themachine that made it, much less how it was made. Thus,it is not surprising for people to utterly fail to make anyimprovement in web flatness.

Yet there is good cause for hope. It begins byunderstanding what bagginess really is. However, the realprogress is made when you let a particular process tell youabout itself and when you use those measures of bagginesswhich do work in a particular situation. The search for thesource of the defect can be minimized by looking onlywhere materials can be permanently distorted. The sourceof the defect may reveal itself merely by the location andshape of the bagginess profile.

Bagginess ProblemsThere are several difficulties posed by the baggy

web. First, the visual appearance of a baggy web is not asappealing as a flat web. Mere cosmetic differences canmake the difference between keeping an order and losingit to a competitor, much as a dent in a fender can reducethe appeal and thus value of a car. Second, the baggy webmay not coat or laminate well. In the former case, levelingcoaters such meir rod and knife coaters will leave morecoating in the baggy area than in the tight area. In the lattercase, the baggy web may refuse to bond flat to its mate,with voids or wrinkles as a result. Third, the baggy portionmay float over rollers causing process difficulties such asbackside treat on a corona treater. Fourth, the baggyportion of the web may not wind the same as the tighterportions. Fifth, the cambered web, which is a subset ofbagginess, can cause guiding, tracking and web pathcontrol problems. These would obviously raise havoc withprinting registrations.

As a final example, the baggy web may not feedwell through machinery as a sheet, such as with theubiquitous paper jam in a copy machine. The most debilitatingcharacteristic of the baggy web, however, is that it simplyrefuses to go through nips. The baggy portion of the webtends to collect behind the nip as a locally loose bulge or‘bubble’. If you are lucky, the bubble will be stable andpresent no great trouble. In other cases, the bubble willgrow with time until it gets large enough to be entrainedinto the nip in a gulp, leaving the telltale smile or angledwrinkle in its wake. The reason the baggy web collects ina bubble is that it is an area of longer ‘natural length’. Sincethe nip is essentially a metering device, the longer baggyportion accumulates and gets behind the tighter portion. Ifwe did not have to get the web through a nip, the bagginessmight otherwise pose few problems in many processes.



Unfortunately, the nip is ubiquitous in converting as this ishow we do calendering, coating, laminating, printing,winding and many other vital manufacturing steps.

Bagginess DefinedBagginess can be defined in at least three entirely

equivalent ways: as a deviation of flatness, a deviation ofstress, or a deviation of strain. This gives us the flexibilityto choose whichever means is most convenient to workwith in any particular situation. Since they are equivalent,a web will either be baggy or will be not baggy by any ofthe definitions. It is also possible to quantitatively convertfrom one measure to another, albeit with some difficulty.

The easiest definition of bagginess is a web thatrefuses to lay/run flat and straight. While it is possible touse this definition for a web running in a machine, it is muchsafer to do so on an inspection table where the web is underno external stresses that can disturb flatness. The risk isthat the web can appear to be baggy in a machine sectiondue to nonuniformities of the machine itself, such ascaused by rollers with are misaligned or vary in diameteracross their widths. Experienced operators will comparethe appearance of the web in several sections of themachine to tell the difference between crooked web andcrooked machine. A web that is baggy will appear loose inthe same CD positions in most spans.

On the other hand, the web may be tight on thefront in one section and loose on the back in the next if themachine is crooked. An exception to this material/machinediscrimination technique is with machines with excessivedeflection, such as is common on cantilevered machinery.For example, a flat web may appear loose and baggy on thefront side of every section because the spans are shorteneddue to roller bending.

Thus, it is much safer to remove the influences ofthe machine when diagnosing bagginess. On an inspectiontable, the baggy web will either not lay flat, or the edges willnot be straight or both. The exceptions to this simple testare obvious and include hard wrinkles and curl that cancause the web to not lay dead flat even when it is notbaggy. The visual inspection technique is quick, simple andcan be far more sensitive than measurements made byinstrument.

A more quantitative definition of bagginess can bemade based on stress variations. A baggy web is onewhose stresses are not uniform. These stresses may varyeither with respect to MD (machine direction or downweb)position or more typically CD (cross direction or transversedirection) position, or both. The stresses of concern aremost typically MD, but could be CD or inplane shear. This

Continued... definition must be tempered so that any stress variationscaused by the machine, such as by crooked or unevenrollers, temperature variations and so on are factored out.Again, we see the challenge of cleanly separating materialfrom machine.

In metals and other industries, these variations ofstress are known as residual stresses. The part releasedfrom the mold or die has stresses locked inside, perhapsdue to uneven cooling rates or forming strain variations.These stresses on thick parts are, for the most part,invisible as they are insufficient to cause significantgeometry changes when resisted by the part’s stiffness.This does not mean that the stresses are insignificant.Composite roller covers can have so much residual (hoop)stress locked in due to shrinkage during curing that theycan split open like an over-ripe radish merely sitting instorage. Sometimes residual stresses are intended anduseful, as illustrated by safety glass on automobile windows,which is designed to shatter into small pieces rather thaninto large wicked shards. The web, on the other hand, hasvery little bending stiffness, which goes as the fourthpower of caliper, and thus responds much more visibly toresidual stresses.

Alternatively, we can define a baggy web as onewhose strains are not uniform. Again, the strains mayvary with MD, CD or both. Again, the strains may be MD,CD or inplane shear or a combination. Mechanics peoplehave long been comfortable with the interchangeability ofstresses and strains through material relationships such asHooke’s Law. While the stress-based definition is moreintuitive, the strainbased definition offers more options formeasurement such as by the bow, fold or strip testtechniques.

Taxonomy of BagginessA complete description of bagginess would specify MD,CD and inplane shear stresses at all points in the web,much as you might obtain as output from a FEM (FiniteElement Model) for a plane stress case. However, thisdetailed mapping of residual stresses is neither practical,nor necessary.

Since bagginess tends to favor certain patterns,we need only to describe and discriminate between them.The first simplification is to focus on MD stress distributionsrather than on CD or inplane shear stresses. There areseveral reasons for this. The MD stress variations tend tolarger values in real webs. They are also easier to measureand more intuitive because we are already accustomed tothinking about that direction when working on drives andtension controls. Finally, MD stress variations capture theessence of most problems.

Part two of this article will appear in the next issue.


.



TECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESBy: Larry Pyle, LFPtechnologies

CUTTING THIN MATERIALSProducing gaskets or other similar products

from thin materials can be the most difficult. Thin gasketsare use in a variety of sizes and quantities. The mostdifficult are those with large plan areas and delicatesections that may require special handling because oftheir fragility.

Thin materials are cut all the time in a lot ofindustries. For instance, companies like Avery OfficeProducts specializes in kiss cutting labels by the billions.Their finished labels are relatively small in plan area. Theequipment is designed specifically for their products andmost likely incorporates rotary dies that can operate atextremely high speeds and precision. It is easy to controlthe nip of two rolls.

Most gasket fabricators have equipment thatwill be an adequate job of cutting a variety of materialthickness and plan areas. The majority of materials are1/64” thick at the minimum and 1/8” at the maximum.They have available a lot different types of equipment fordoing their cutting:

• Punch presses (solid bed)• Hydraulic table presses• Traveling bed, moveable head presses• Lasers• Water jet

And a variety of tool types are used:

• All steel male/female tools• Steel rule dies• Steel punches

Each of these types of equipment and toolingcombinations has its own set of challenges when cuttingthin materials. Clean cuts and parts removal are theprime consideration for success. This is most easilycontrolled on small parts and stiff, small bed, presses likePreco’s or some larger traveling bed presses. Cuttingthrough using steel rule or punches into a soft surface willproduce cleaner cuts. A sacrificial surface that is movedever so slightly with each cut has been used with goodresults. If the part is extremely large and the only optionis a large bed press interleaving with chipboard has beenused although it is very labor intensive, slow and costlyprocess.

In summary, each part, thickness and piece ofequipment is unique to each fabricator. The volumes thatare typically produced with each setup are relatively small.The method, which produces the cleanest cuts, the leastbreakage and the easiest setup, is the one that should beused. If none of the options are acceptable, a new dedicatedsystem for cutting thin materials may be in order.

LAMINATESA laminate is a material constructed by uniting, or

bonding, two or more solid layers of material together. Theprocess of creating a laminate is lamination. Laminates thatmight be found in other industries include laminated flooring(layers of wood), plywood (oriented wood layers), drywall(a layer of gypsum with paper surfaces), etc.

As the subject of this article, most of the discussionwill be related to typical types of laminates used as gasketsand will be limited to solid layers. Tanged steel core andwire screens will not be discussed because the cores are notsolid and uniform.

Each layer (or sheet) in the laminate is generallyuniform in thickness but can contain porosity or orientationof individual components within the layer. For example,gasket papers contain differing properties between the MD(machine direction) and CMD (cross machine direction) asthe paper is formed during the paper making process. Thefibers, fillers and binders become oriented during the process.

Types of laminate used in gaskets:

Paper-metal laminates. The most common of thesewould be a gasket paper adhesively bonded to a metal core.The purpose of the metal layer would be: 1) improvedimensional stability, 2) provide rigidity to the end product,3) improve compression or crush properties. Anotheradvantage of this type of construction is that the overallthickness of the laminate can be changed by adding thicknessto the metal layer while keeping the thickness of the top andbottom layers of paper constant thus keeping the torqueretention properties of the laminate the same (see figure Aon page 14).


The metal core is carefully prepared in orderto achieve an optimum bond. Preparation may consistof mechanical abrasion and chemical treatments. Thelamination process may be:• Continuous starting with coils of metaland paper. This is the preferred process for a moreconsistent product. The laminate can either be coiledor cut into sheets at the end of the process. Theadhesive that combines the layers can be applied wetas part of the process or be pre-applied to either themetal or the paper. Some products use an aqueousadhesive that is usually post cured after the product islaminated. Others will use a pre-applied thermo-settingor thermo-plastic adhesive applied to the metal core.This adhesive would be activated either in-line with aheat source and pressure source (usually hydraulicallyloaded rolls), or post cured under pressure and heat.The adhesive must be in a tacky state when thelamination pressure is applied. Dissimilar non-metallicmaterials are sometimes laminated.• Lamination of sheets. This contains thesame process elements as the continuous process.This would be done in smaller batches or when fragilematerials are used as part of the laminate. Oneexample would be the use of soft top and bottom layers(cork or cork-rubber, rubber foam, rubber etc.)laminated to a solid steel center core. The core is pre-coated with a heat activated thermo-setting adhesive.Multiple laminates are stacked in a fixture at room

temperature. The fixture consists of tap and bottom steelplates and threaded rods and nuts. It also contains a means forkeeping the stacked layers in plate. After the fixture isassembled, the nuts are tightened to put the desired pressureon the stack. Assembled fixtures are then transferred to anoven where the curing of the adhesive is done. After cooling,the stack is separated and the laminates are ready for furtherprocessing.

Thick gaskets: Occasionally, a gasket design requires athickness of material that cannot be produced to the desiredthickness in a single layer. Laminating two or more thin layerstogether using an adhesive produces the desired thickness.

Installation aids: One commonly used laminate for use asgaskets is the use of an adhesive layer on one side that attachesthe gasket to the application as an installation aid. Commonlythis is accomplished by laminating a gasket material with PST(pressure sensitive tape). The resultant finished gasket consistsof a gasket layer, adhesive layer and a silicone treated layerthat is removed just prior to assembly on the application.

Caution regarding laminates:

The integrity of the laminate is only as strong as the adhesivethat bonds the layers together.• Surface preparation is important. Adhesives don’tadhere well to papers, which have release coatings.• Make sure that the adhesive is properly cured to its’full strength and most importantly that it is compatible with theenvironment that it will see in the application. Incompatibilitymay turn the adhesive into a lubricant that can result indisastrous results.• Tension during a continuous process of laminationshould be the minimum necessary to produce a flat, consistentlaminate. Too much tension will result in paper breakage andstretching of any material. Materials that are innately weak orstretchy, the more precise must be the tension control. As thediameter of the feed roll decreases, the tension in the materialmay increase due to the reduced leverage any more complextensioning and alignment controls may be necessary.

TECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESTECHNICAL ARTICLESBy: Larry Pyle, LFPtechnologies

LAMINATESContinued from page 13...

Figure A

If you have technical questions you would like tosee answered in future issues, please send them

by e-mail to [email protected].


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THE GASKET FABRICATORPAGE 2 THE GASKET FABRICATOR DECEMBER 2007 NEW ASSOCIATION MEMBERS Fabricators...

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