Workshop Manual 2016

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LABORATORY MANUAL

OF

WORKSHOP PRACTISE

Department of Mechanical Engineering

Muffakham Jah College of Engineering and Technology(THE SULTAN UL ULOOM EDUCATION SOCIETY)

Affiliated to Osmania University & Recognized by AICTE

Banjara Hills, Hyderabad 5000 34


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The following faculty members has contributed for preparing the Workshop Practice manual.

CARPENTRY O.Hemalatha & Hasham Ali

FITTING Syed Khader Basha & G Bhasker

HOUSE WIRING Afroz Mehar & G Sailaja

PLUMBING G Prasanna Kumar & H K Dora

SHEET METAL V Dharam Singh & S Irfan Sadak

WELDING Abdul Rahim Junaidi & Md Yahiya

Work shop Incharge Module Co ordinator Program Co ordinator HOD

Joseph George Konnuly J. Dhanraj Pamar AS Reddy/SE Khainy Dr.Shaik Khader Vali


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CARPENTRY


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INSTRUCTIONS TO THE STUDENTS

1. Enter the lab with proper dress- code (blue apron and shoes)

2. Maintain a 200 pages white long note book and divide it into four parts with the Titles of the

trades namely foundry, plumbing, black smithy and Welding.

3. Draw the figures of tools and equipments proportionately using pencil only on the left side of

the page.

4. Write the related theory part only on the right side of the page.

5. For every experiment, draw the related figure and write the individual procedure in the

observation book and take signature by the concerned technician. Write the date and Experiment

number in the observation book. And take signature of staff member on index page of lab manual.

6. Only after taking signature in the observation book, write the record. Both will be checked.

Marks are allotted for your regularity. Performance of the students will be assessed for every

session of workshop being conducted.

7. The records should be written up to date without delay. They should be signed by the

concerned faculty.

8. Medical kits provided in the FirstAid Box. The students can utilize the available Medicines

if at all there is any necessity.


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INDEX

1. CARPENTRY

Introduction

Tools

Safety precautions

Exercises

1.

Practice in Planning, sawing and chiseling

2. Preparing cross Half Lap Joint

3. Preparing Dove Tail Joint.

BEYOUND THE SYLLABUS:

1. Preparing the Mortise and Tenon joint


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CHAPTER-1

CARPENTRY

INTRODUCTION:

Carpentry may be defined as the process of making wooden articles and components such as

roots, floors, partitions, doors and windows. Carpentry involves cutting, shaping and fastening

wood and other materials together to produce a finished product. It deals with the building work,

furniture, either, cabinet, making , etc, Joinery. Preparation of joints is one of the important

operations in wood work. Joinery denotes connecting the wooden parts using different points such

as lap joints, mortise and T- joints, bridle joints, etc.

In carpentry workshop, wooden pieces of commercial sizes are given specific shape and size, as

per the requirements. The processes involved in carpentry shop are making layout, marking,

sowing, planning, chiseling joint making etc.

The raw material and tools used in carpentry shop are various are wood, nut, screw, nut and bolt

and glue etc. The tools are classified as marking, cutting, planning, chiseling, striking etc.

VARIOUS TYPES OF TIMBER AND PRACTICE BOARDS

Types of WoodCommon wood are generally classified according to their degree of hardness of

softness.

1. Hardwood- Hard wood has closed structure, heavy in weight, dark in color and is difficult

to work on it, annual rings are not distinct and good tensile strength.

2. Soft Wood- Hard wood has less weight, less durable and is easy to work out. Soft wood

catches fire soon as compared to hardwood, annual rings are quite distinct.

3. Plywood: It consists of more than three layers. Middle layer is called care which is thick and

not of good quality. The top and bottom are called as face plys which is glued on the care attop and bottom. The grains of adjacent layers are kept perpendicular to each other which prevents

plywood form war page.

Types of PlyPly Board, Commercial Board, Chip Board, Soft Board.

Advantage of Ply wood

1. Lighter in weight and easy to work.

2. Can be used for decorating the furniture as well as houses.

3. It is also available in bigger sizes.


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4. Possesses bottom strength then solid wood of same thickness.

CHARACTERISTICS OF GOOD TIMBER

Timber is the name given to the wood obtained from well grown trees. The trees are cut, sawn

into various sizes to suit building purposes.

The word, grain , as applied to wood, refers to the appearance or pattern of the wood on the cut

surfaces. The grain of the wood is a fibrous structure and to make it string, the timber must be so

cut, that the grains run parallel to the length.

The good timber must possess the following characteristics

a. It should have minimum moisture content, i.e., the timber should be well seasoned.

b. The grains of wood should be straight and long.

c. It must retain its straightness after seasoning.

d. It should produce near metallic sound on hammering.

e. It should be free from knots or cracks.

f. It should be of uniform color, throughout the part of the wood.

g. It should respond well to the finishing and polishing operations.

h. During driving the nails and screw, it should not split easily.

MARKET SIZES OF TIMBER:

Timber is sold in the market in various standard shapes and sizes. The following are the common

shapes and sizes:

1. LogThe trunk of the tree, which is free from branches.

2. BalkThe log, sawn to have roughly square cross-section.

3. PostA timber piece, round or square(sawn) in cross section , having its diameter or side,

varying from 175 to 300 mm.

4. PlankA sawn timber piece, with more than 275 mm in width, 50 to 150 mm in thickness

and 2.5 to 6.5 meters in length.

5. BoardA sawn timber piece, below 50 mm thickness and more than 125 mm in width.

6. BattenA sawn timber piece, below 175 mm in width and 30 to 50 mm in thickness.

7. Scantlings or reaperssawn timber pieces of assorted and non- standard sizes, which do

not confirm to the above shapes and sizes.

DEFECTS IN TIMBER


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Following are the common defects occurring in the wood and it can be divided into following

three categories.

1. Natural Defects are the defects which are caused in the tree due to abnormality in the grouts.

2. Defects are also caused during seasoning operation.

3. Some defects are also there due to termites or insects.

Natural defectsWood being a product of nature is subjected of natural defects, some of them

are explained below:

1. Shakes: Shakes are caused due to the separation of wood grains, some times, burning of

tissues and shrinkage of interior parts takes place which causes radial or circular rupture in

tissues and creates cavities, which are called shakes are of three types

(i) Heart and star shakes: These defects in the heart wood in other older tree, especially.

Hemlock heart shakes can be evidenced by a small point cavity at the center of the wood as

shown in fig.

(ii) Wind shakes or Cup shaker: The separation of annual rings is called wind shake or cup

shake. These defects are common in lines.

(iii) Radial Shakes: Radial shakes are the radial splits extending from bark towards the center.

These cracks over the cross section of the log are winder at the bark and narrow down near the

center as shown in fig.

2. Knots: Knot represent irregular in the body of a tree which interrupt the smooth course of the

grand. The fibers of the tree are turned from their normal shaped and grow around the knot at

that point of a tree where a link is being formed. Knots are two types:

(i) Dead knots: When the separation of benches or hurbs takes place before the tree is cut,

the knot thus formed called leaf knot. This knot is not held firmly and wood having leaf knot

is not recommended for engineering purposes.

(ii) Live knots: If the separation occurs after falling of a tree the knot thus formed is called

live knot. A wood having live knot can be used for engineering purposes.

SEASONING OF WOOD

The process of removing moisture from freshly cut down trees is known as seasoning. In these

trees the percentage of moisture is very high. The wood uses of engineering purposes containing

high percentage of moisture may cause many types of problems, such as shrinkage, warpage

distortion etc. To a point this, seasoning is done. After seasoning the percentage of moisture is

reduced to 10- 20%.

Types of Seasoning


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(i) Air Seasoning: In this method, the timber balks are stacked in a sheet such that they are not

directly exposed to sun and rain but a free circulation of air takes place through them. The timber

balks are allowed to remain in that condition for a long times. The balks be periodically turned

upside which accelerates the rate of drying. Due to the circulation of free air through the stack,

the excess moisture evaporates and the wood gets seasoned. This is the commonly used method

which takes much time but proper seasoning can be easily done with a little care.

(ii) Water Seasoning: In this method, timber balks are immersed in flowing water for a fortnight.

The flowing stream of water removes the sap. The timber is then taken out and air seasoning is

done as usual. This method takes less time but the strength of wood reduced.

(iii) Artificial or Kiln Seasoning: This is a quick process of seasoning of this method,

the timber balks are stacked and over large trollies which are then driven into hot chambers or

kilus. Hot air or dry stem is pushed into the chamber under controlled temperature conditions.

The moisture content is reduced because the evaporation takes place and ultimately the timber

gets seasoned.

TOOLS

MARKING AND MEASURING TOOLS

Accurate marking and measurement is very essential in carpentry work, to produce parts to

exact size. To transfer dimensions onto the work; the following are the marking and measuring

tools that are required in a carpentry shop.

1. Steel rule and Steel tape

Steel rule shown in Figure 1.1a is a simple measuring instrument consisting of a long, thin metal

strip with a marked scale of unit divisions. It is an important tool for linear measurement.

Steel tapeshown in figure 1.1b is used for large measurements, such as marking on boards and

checking the overall dimensions of the work.

Figure 1.1a: Steel rule


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Figure 1.1b:Steel tape

2. Marking gauge

Marking gauge shown in figure1.2.a is a tool used to mark lines parallel to the edge of a wooden

piece. It consists of a square wooden stem with a sliding wooden stock (head) on it. On the stem

is fitted a marking pin, made of steel. The stock is set at any desired distance from the marking

point and fixed in position by a screw. It must be ensured that the marking pin projects through

the stem, about 3 mm and the end are sharp enough to make a very fine line.

A mortise gauge shown in Figure 1.2.b consists of two pins. In this, it is possible to adjust the

distance between the pins, to draw two parallel lines on the stock.

a. Marking gauge b. Mortise gauge

Figure 1.2: Marking gauges

3 Trysquare

Try square shown in figure 1.3 is used for marking and testing the squareness and straightness of

planed surfaces. It consists of a steel blade, fitted in a cast iron stock. It is also used for checking

the planed surfaces for flatness. Its size varies from 150 to 300 mm, according to the length of the

blade. It is less accurate when compared to the trysquare used in the fitting shop.


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Figure 1.3: Try square

4. Compass and divider

Compass and divider shown in figure 1.4, are used for marking arcs and circles on the planedsurfaces of the wood.

5. Scriber or marking knife

Scriber as shown in figure1.5a is used for marking on timber. It is made of steel having one end

pointed and the other end formed into a sharp cutting edge.

6. Bevel

Bevel as shown in figure 1.5b is used for layingout and checking angles. The blade of the bevel

is adjustable and may be held in place by a thumb screw. After it is set to the desired angle, it can

be used in much the same way as a trysquare. A good way to set it to the required angle is to

mark the angle on a surface and then adjust the blade to fit the angle.

Figure 1.4: Compass and Divider


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Figure 1.5a.Scriber or marking Knife

Figure 1.5b: Bevel

HOLDING TOOLS

1 Carpenter's vice

Figure1.6 shows the carpenter's bench vice, used as a work holding device in a carpenter shop.

Its one jaw is fixed to the side of the table while the other is movable by means of a screw and a

handle.

The Carpenter's vice jaws are lined with hard wooden' faces.

Figure 1.6: Carpenters vice


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Figure 1.7: Cclamp

2. Cclamp

Figure 1.7 shows a Cclamp, which is used for holding small works.3. Bar cramp

Figure 1.8 shows a bar cramp. It is made of steel bar of Tsection, with malleable iron fittings

and a steel screw. It is used for holding wide works such as frames or tops.

Figure 1.8:bar cramp

PLANING TOOLS

Planing is the operation used to produce flat surfaces on wood. A plane is a hand tool used forthis purpose. The cutting blade used in a plane is very similar to a chisel. The blade of a plane is

fitted in a wooden or metallic block, at an angle.

1. Jack plane


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Jack Plane as shown in figure 1.9 a & b is the most commonly used general purpose plane. It is

about 35 cm long. The cutting iron (blade) should have a cutting edge of slight curvature. It is

used for quick removal of material on rough work and is also used in oblique planning.

2. Smoothing plane

Smoothing Plane as shown in figure 1.9c is used for finishing work and hence, the blade should

have a straight cutting edge. It is about 20 to 25 cm long. Being short, it can follow even the slight

depressions in the stock, better than the jack plane. It is used after using the jack plane.

3. Rebate plane

Rebate Plane as shown in figure 1.9d is used for making a rebate. A rebate is a recess along the

edge of a piece of wood, which is generally used for positioning glass in frames and doors.

4. Plough plane

Plough Plane as shown in figure 1.9e is used to cut grooves, which are used to fix panels in a

door. Figure .9 shows the various types of planes mentioned above.

a)Wood jack plane ` b)Metal jack plane

c)smoothing Plane d) Rebate plane


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e) Plough Plane

Figure 1.9: Types of planes

CUTTING TOOLS

1. Saws

A saw is used to cut wood into pieces. There are different types of saws, designed to suitdifferent purposes. A saw is specified by the length of its toothed edge.

i) Crosscut or hand saw

Cross cut saw as shown in figure1.10 is used to cut across the grains of the stock. The teeth are so

set that the saw kerf will be wider than the blade thickness. This allows the blade to move freely

in the cut, without sticking.

ii) Rip saw

Rip saw as shown in figure 1.10 is used for cutting the stock along the grains. The cutting edge of

this saw makes a steeper angle, i.e., about 60 whereas that of crosscut saw makes an angle of 45

with the surface of the stock.

iii) Tenon saw

Tenon saw as shown in figure 1.11 is used for cutting the stock either along or across the grains.

It is used for cutting tenons and in fine cabinet work. However, it is used for small and thin cuts.

The blade of this saw is very thin and so it is stiffened with a thick back steel strip. Hence, this is

sometimes called as backsaw. In this, the teeth are shaped like those of crosscut saw.

iv) Compass saw

Compass saw as shown in figure 1.12 has a narrow, longer and stronger tapering blade, which is

used for heavy works . It is mostly used in radius cutting. The blade of this saw is fitted with an

open type wooden handle.


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Figure 1.10: Cross cut and rip saw

Figure 1.11: Tenon Saw

Figure 1.12: Compasss Saw

2. Chisels

Chisels are used for cutting and shaping wood accurately. Wood chisels are made in various

blade widths, ranging from 3 to 50 mm. They are also made in different blade lengths. Most of

the wood chisels are made into tang type, having a steel shank which fits inside the handle (Figure

1.13). These are made of forged steel or tool steel blades.

Figure 1.13: Parts of chisel


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i) Firmer chisel

The word 'firmer' means 'stronger' and hence firmer chisel is stronger than other chisels. It is a

general purpose chisel and is used either by hand pressure or by a mallet. The blade of a firmer

chisel is flat, as shown in Figure 1.14 a.

ii) Dovetail chisel

It has a blade with a beveled back, as shown in Figure, due to which it can enter sharp comers

for finishing, as in dovetail joints, as shown in figure 1.14b

iii) Mortise chisel

Mortise chisel as shown in figure 1.14c is used for cutting mortises and chipping inside holes, etc.

The crosssection of the mortise chisel is proportioned to withstand heavy blows during

mortising. Further, the crosssection is made stronger near the shank.

a. Firmer b. Dovetail c. Mortise

Figure 1.14: Types of chisels

DRILLING AND BORING TOOLS

1. Carpenters brace

Carpenters brace as shown in figure 1.15a is used for rotating auger bits, twist drills, etc., to

produce holes in wood. In some designs, braces are made with ratchet device. With this, holes

may be made in a corner where complete revolution of the handle cannot be made. The size of a

brace is determined by its sweep.


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2. Auger bit

Auger bit as shown in figure 1.15b is the most common tool used for making holes in wood.

During drilling, the lead screw of the bit guides into the wood, necessitating only moderate

pressure on the brace. The helical flutes on the surface carry the chips to the outer surface.

3. Hand drill

Carpenter's brace is used to make relatively large size holes; whereas hand drill as shown in

figure 1.15c is used for drilling small holes. A straight shank drill is used with this tool. It is

small, light in weight and may be conveniently used than the brace. The drill bit is clamped in the

chuck at its end and is rotated by a handle attached to gear and pinion arrangement.

4. Gimlet

Gimlet as shown in figure 1.15d has cutting edges like a twist drill. It is used for drilling large

diameter holes with the hand pressure.

a) Carpenters brace b) Auger Bit c) Hand Drill d) gimlet

Figure 1.15: Drilling tools

MISCELLANEOUS TOOLS

1. MalletMallet as shown in figure 1.16a is used to drive the chisel, when considerable force is to be

applied, which may be the case in making deep rough cuts. Steel hammer should not be used for

the purpose, as it may damage the chisel handle. Further, for better control, it is better to apply a

series of light taps with the mallet rather than a heavy single blow.

2. Pincer


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It is made of two forged steel arms with a hinged joint and is used for pullingout small nails

from wood. The inner faces of the pincer (figure 1.16b) jaws are beveled and the outer faces are

plain. The end of one arm has a ball and the other has a claw. The beveled jaws and the claw are

used for pulling out small nails, pins and screws from the wood.

3. Claw hammer

It has a striking flat face at one end and the claw at the other, as shown in figure1.16c. The face is

used to drive nails into wood and for other striking purposes and the claw for extracting relatively

large nails out of wood. It is made of cast steel and weighs from 0.25 kg to 0.75 kg.

4. Screw driver

It is used for driving screws into wood or unscrewing them. The screw driver of a carpenter is

different from the other common types, as shown in figure1.16f The length of a screw driver is

determined by the length of the blade. As the length of the bladeincreases, the width and thickness

of the tip also increase.

5. Wood rasp file

It is a finishing tool used to make the wood surface smooth, remove sharp edges, finish fillets

and other interior surfaces as shown in figure1.16d. Sharp cutting teeth are provided on its surface

for the purpose. This file is exclusively used in wood work.

6. Bradawl

It is a hand operated tool, used to bore small holes for starting a screw or large nail.as shown in

figure 1.16e

a.Mallet


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For marking with the help of a marking gauge, it must be held firmly with fingers around the head

and with the thumb behind the marking point and the gauge must be pushed forward against the

surface. While pushing, the gauge must be kept slightly forward so that , the point gets dragged at

a slight angle.

If the work is to be finished with a plane, an allowance must be provided for this, while marking

However, it must be borne in mind that removing excess material with a plane is a tedious job and

hence should be kept to a minimum.

Laying-out an Angle

The following are the steps involved in laying-out an angle on a wooden surface.

1. Set the bevel to the required angle.

2. Hold the handle firmly against the face or edge of the board.

3. Mark along the edge of the blade with a pencil or knife.

Plane Adjustment

A plane will not produce proper work surface unless the blade is sharp and properly adjusted.

Out of the two adjustments that are in built in the design of the plane, one is to regulate the depth

of cut and the other is to straighten the blade so that , it produces a flat surface.

The plane adjustment may be checked by feeling the corners of the blade with the first two

fingers. By this, it may be easily detected and adjusted if one corner projects through the throat

farther than the other. For proper work, turn the adjustment nut until a fine shaving is cut when

the plane is moved over the surface.

Method of using the plane.

The following may be noted while using the plane:

1. Hold the handle of the plane with the right hand and the knob with the left band.

2. Stand to the left side of the job, feet apart and with the left foot slightly ahead.

3. While pushing the plane, gradually shift weight to the left foot.

4. While planning , keep the fore arm straight in-line behind the plane

NOTE: i) Always plane along the grains. Planning against the grains will result in rough work.

ii) When not in use, lay the plane on its side. This prevents the cutting edge becoming dull

by contact with the bench top.

Planing a Surface

Planing is the first thing to be done to build any project in carpentry. The following are the steps

involved in planning a surface:

1. Beginning at one edge of the stock, plane with full length strokes to the other edge.


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2. Use the edge of a steel rule to test the surface , by placing the edge in various positions on

the surface and see the underneath to locate high and low places. For this , the order of

checking is as follows:

i) First place the straight edge cross-wise on the stock and move it slowly from one

end to the other.

a. Butt b. Dowell c. Dado d. Rabbet

e. Lap f. Mortise and tenon g. Miter

Figure 1.17: Common wood joints

Lap joints

In lap joints, an equal amount of wood is removed from each piece, as shown in figure 1.17. Lap

joints are easy to layout, using a trysquare and a marking gauge. The layout may also be made by

lapping the pieces to be joined and along the edge of one piece, marking lines on the other.

Here too, while laying-out the joint, Follow the procedure suggested for sawing and removing the

waste stock. If the joint is found to be too tight, it is better to reduce the width of the mating piece,

instead of trimming the shoulder of the joint. This type of joint is used for small boxes to large

pieces of furniture.

SAFE PRACTICE

General

1. Tools that are not being used should always be kept at their proper places.

2. Make sure that your hands are not in front of sharp edged tools while you are using them.


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3. Use only sharp tools. A dull tool requires excessive pressure, causing the tool to slip.

4. Wooden pieces with nails, should never be allowed to remain on the floor.

Saws

Be careful when you are using your thumb as a guide in crosscutting and ripping.

Chisels

1. Test the sharpness of the cutting edge of chisel on wood or paper, but not on your hand.

2. Never chisel towards any part of the body.

Screw driver.

1. Select the longest screw driver that is appropriate for the job intended. The longer the tool

, the greater the effort applied.

2. The tip of the screw driver must fit the slot without wobbling. The width of the tip should

be equal to the length of the screw slot.

3. Keep the screw driver properly pointed to prevent injury to hands.

CARE AND MAINTENANCE OF TOOLS

Chisels

1. Do not use chisels where nails are present.

2. Do not use chisel as a screw driver.

Saws

1. Do not use a saw with a loose handle.

2. Always use triangular file for sharpening the teeth.

3. Apply grease when not in use

EXERCISE-1

AIM: To make the wooden piece according to dimensions given , it is the exercise for practice in

planning , sawing and chiseling.


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ALL DIMENSIONS ARE IN MM


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Material Required: Teak Wood dimensions : 300 mm x 50 mm. x 25 mm.

Tools required :Jack Plane, tenon saw, chisel, mallet.Measuring and marking tools:Marking gauge, steel scale , try square.

Procedure:

Order of operation:

1. Choose the better one the top and bottom surface of the piece and plane it smooth. Test the

two sides with steel scale length wise, cross wise and diagonally for flatness. This will be

FACE SIDE and is marked thus& with the tail towards the better edge.

2. Place the work piece in the vice and plane this edge. This will be FACE EDGE. Test it

with steel scale as before and check squareness with the face side by a try square. Mark it

thus with the apex towards the face side.

3. Mark a line with marking gauge 45 mm away from the FACE EDGE.

4. Place the work piece in the vice and plane this edge down to the marked gauge line. Test

with steel scale and try square.

5. Mark a line with marking gauge 20 mm. away from the face edge. Make correspondingly

on the opposite edge.

6.

Place the work piece with face down and plane the bottom side upto the gauge line on

both the edges. Test its squareness and trueness as before.

THE WORK PIECE HAS NOW BEEN PLANES TRUE AND SQUARE

7. Draw a line 10mm. away from the face side on the face edge.

8. With the pencil point locate the positions of the slots according to given sketch . before

this operation remove about 10 mm, from either side as waste wood and start marking

from this line.


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9. Using the try square mark slots with pencil on the face side.

10.Square down these lines upto gauge lines on the two face edges.

11.Mark X over the work piece an portions to be removed.

12.Make saw cuts close up against the lines on the face side and upto gauge lines on the

edges. The cuts should be towards the portion to be removed.

13.Fix the work piece again and chisel out the slots, starting from top to bottom at an angle

and gradually reaching the gauge line. reverse the work piece and repeat the same

operation. Finally, clear the bottom portion of each slot smooth and flat.

14.Saw out the waste wood from both the ends.

NOTE:

1. Use a chisel of smaller size than the slot to be cut.

2. Be careful to see the saw does not run out of the marked lines.

EXERCISE-2

AIM: To make the Cross Half Lap Joint according to the given dimensions, from the given

wooden

piece .



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Tools required :Jack Plane, tenon saw, chisel, mallet.

Measuring and marking tools:Marking gauge, steel scale , try square.

Procedure:

Order of operation:

1. The given Wooden piece is checked to ensure its correct size.

2. The Wooden piece is firmly clamped in the carpenter's vice and any two adjacent faces

are planed by the jack plane and the two faces are checked for squareness with the try

square.

3. Marking gauge is set and lines are drawn at 44 and 88 mm, to mark the thickness and

width of the model respectively.

4. The excess material is first chiseled out with firmer chisel and then planed to correct size.

5. The mating dimensions of the parts X and Yare then marked using scale and marking

gauge.

6. Using the cross cut saw, the portions to be removed are cut in both the pieces, followed

by chiseling and also the parts X and Yare separated by cross cutting, using the tenon saw.

7. The ends of both the parts are chiseled to exact lengths.

8. A fine finishing is given to the parts, if required so that, proper fitting is obtained.

9. The parts are fitted to obtain a slightly tight joint.

NOTE:



RESULT: The cross half lapjoint is thus madeby following the above sequence of

operations.


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EXERCISE-3

AIM: To make the Dove Tail Joint according to the given dimensions, from the given wooden

piece ..

ALL DIMENSION ARE IN MM


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Procedure:

Order of operation:

10.The given Wooden piece is checked to ensure its correct size.

11. The Wooden piece is firmly clamped in the carpenter's vice and any two adjacent faces

are planed by the jack plane and the two faces are checked for squareness with the try

square.

12. Marking gauge is set and lines are drawn at 30 and 44 mm, to mark the thickness and

width of the model respectively.

13. The excess material is first chiseled out with firmer chisel and then planed to correct size.


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14. The mating dimensions of the parts X and Yare then marked using scale and marking

gauge.

15. Using the cross cut saw, the portions to be removed are cut in both the pieces, followed

by chiseling and also the parts X and Yare separated by cross cutting, using the tenon saw.


17. A fine finishing is given to the parts, if required so that, proper fitting is obtained.

18. The parts are fitted to obtain a slightly tight joint.

NOTE:



RESULT: TheDove tail Lapjointisthusmadebyfollowingtheabovesequenceof

operations.

EXERCISE-4

AIM: To make the Mortise and Tenon Joint according to the given dimensions, from the given

wooden piece .

X Y



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Procedure:

Order of operation:

1. The given Wooden piece is checked to ensure its correct size.

2. The Wooden piece is firmly clamped in the carpenter's vice and one of its faces are planed

by the jack plane and checked for straightness.3. The adjacent face is then planed and the faces are checked for squareness with the

try square.

4. Marking gauge is set and lines are drawn at 30 and 45 mm, to mark the thickness andwidth of the model respectively.


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5. The excess material is first chiseled out with the firmer chisel and then planed to correct

size.

6. The mating dimensions of the parts X and Yare then marked using the scale and marking

gauge.7. Using the cross cut saw, the portions to be removed in part Y (tenon) is cut, followed by

chiseling.

8. The material to be removed in part X (mortise) is carried out by using the mortise and

firmer chisels.9. The parts X and Yare separated by cross cutting with the tenon saw.


11. Finish chiseling is done wherever needed so that, the parts can be fitted to obtain a near

tight joint.

NOTE:



RESULT: Themortiseandtenonjointisthusmadebyfollowingtheabovesequenceof

operations.


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FITTING SHOP


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CONTENTS

Preface

Table of Contents

page

1. Fitting Shop

1.1 Introduction

1.2 Holding tools

1.3 Marking and measuring tools

1.4 Cutting tools

1.5 Finishing tools

1.6 Miscellaneous tools

1.7 Safe practice

1.8 Models for preparation

Exercises


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FITTING SHOP

1.1 INTRODUCTION

Machine tools are capable of producing work at a faster rate, but, there are

occasions when components are processed at the bench. Sometimes, it becomes

necessary to replace or repair component which must be fit accurately with another

component on reassembly. This involves a certain amount of hand fitting. The assembly of

machine tools, jigs, gauges, etc, involves certain amount of bench work. The accuracy of

work done depends upon the experience and skill of the fitter.fitting deals which the assembly

of mating parts, through removal of metal, to obtain the required fit.

Both the bench work and fitting requires the use of number of simple hand tools

and considerable manual efforts. The operations in the above works consist of filing,

chipping, scraping, sawing drilling, and tapping.

1.2 HOLDING TOOLS

1.2.1 Bench vice

The bench vice is a work holding device. It is the most commonly used vice in a fitting

shop. The bench vice is shown in Figure 1.1.

Figure 1.1: Bench

Vice

It is fixed to the bench with bolts and nuts. The vice body consists of two main parts,

fixed jaw and movable jaw. When the vice handle is turned in a clockwise direction, the

sliding jaw forces the work against the fixed jaw. Jaw plates are made of hardened steel.

Serrations on the jaws ensure a good grip. Jaw caps made of soft material are used to protect

finished surfaces, gripped in the vice. The size of the vice is specified by the length of thejaws.


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The vice body is made of cast Iron which is strong in compression, weak in tension and sofractures under shocks and therefore should never be hammered.

1.2.2 Vblock

Vblock is rectangular or square block with a Vgroove on one or both sides opposite

to each other. The angle of the Vis usually 900. Vblock with a clamp is used to hold cylindrical

work securely, during layout of measurement, for measuring operations or for drilling forthis the bar is faced longitudinally in the VGroove and the screw of Vclamp is tightened.

This grip the rod is firm with its axis parallel to the axis of the vgroove.

1.2.3 CClamp

This is used to hold work against an angle plate or vblock or any other surface, when

gripping is required. ts fixed jaw is shaped like English alphabet Cand the movable jaw is round

in shape and directly fitted to the threaded screw at the end .The working principle of this

clamp is the same as that of the bench vice.

F

Figure 1.2:V-block Figure 1.3:C-clamp

1.3MARKING&MEASURINGTOOlS

1.3.1 Surface P late

The surface plate is machined to fine limits and is used for testing the flatness of

the work piece. It is also used for marking out small box and is more precious than the marking

table. The degree of the finished depends upon whether it is designed for bench work in a fitting

shop or for using in an inspection room; the surface plate is made of Cast Iron, hardened Steel

or Granite stone. It is specified by length, width, height and grade. Handles are provided on two

opposite sides, to carry it while shifting from one place to another.

Figure 1.5: Angle plate Figure 1.4: Surface plate


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1.3.2

Trysquare

It is measuring and marking tool for 90o

angle .In practice, it is used for checking thesquareness of many types of small works when extreme accuracy is not required .Theblade of the Try square is made of hardened steel and the stock of cast Iron or steel. Thesize of the Try square is specified by the length of the blade.

Figure 1.6: Try square

1.3.3

Scriber

A Scriber is a slender steel tool, used to scribe or mark lines on metal work pieces. It is

made of hardened and tempered High Carbon Steel. The Tip of the scriber is generally ground at

12oto 15o. It is generally available in lengths, ranging from 125mm to 250mm .It has two

pointed ends the bent end is used for marking lines where the straight end cannot reach.

Figure 1.7: Scriber

1.3.4 Odd leg Caliper

This is also called Jenny Caliper or Hermaphrodite. This is used for marking parallel

liners from a finished edge and also for locating the center of round bars; it has one leg

pointed like a divider and the other leg bent like a caliper. It is specified by the length of the leg

up to the hinge point.


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1.3.5 Divider

It is basically similar to the calipers except that its legs are kept straight and

pointed at the measuring edge. This is used for marking circles, arcs laying out perpendicular

lines, by setting lines. It is made of case hardened mild steel or hardened and tempered low

carbon steel. Its size is specified by the length of the leg.

1.3.6 Trammel

Figure 1.8: Odd leg caliper and spring divider

Trammel is used for drawing large circles or arcs.

1.3.7 Punches

These are used for making indentations on the scribed lines, to make them visible

clearly. These are made of high carbon steel. A punch is specified by its length and diameter (say

as 15012.5mm). It consists of a cylindrical knurled body, which is plain for some length at the

top of it. At the other end, it is ground to a point. The tapered point of the punch is hardened

over a length of 20 to 30mm.

Dot punch is used to lightly indent along the layout lines, to locate center of holes and toprovide a small center mark for divider point, etc. for this purpose, the punch is ground to aconical point having 60 included angle.

Center punch is similar to the dot punch, except that it is ground to a conical point having 90

included angle. It is used to mark the location of the holes to be drilled.


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Figure 1.9:

Punches

1.3.8 Calipers

They are indirect measuring tools used to measure or transfer linear dimensions. These

are used with the help of a steel Rule to check inside and outside measurements. These

are made of Case hardened mild steel or hardened and tempered low carbon steel. While

using, but the legs of the caliper are set against the surface of the work, whether inside or

outside and the distance between the legs is measured with the help of a scale and the same can

be transferred to another desired place. These are specified by the length of the leg. In the caseof outside caliper, the legs are bent inwards and in the case of inside caliper, the legs bent

outwards.

Figure

1.10:Calipers

1.3.9 Vernier Calipers

These are used for measuring outside as well as inside dimensions accurately. It may

also be used as a depth gauge. It has two jaws. One jaw is formed at one end of its main scale

and the otherjaw is made part of a vernier scale.

Figure 1.11: Vernier caliper


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1.3.10 Vernier Height Gauge

The Vernier Height gauge clamped with a scriber. It is used for Lay out work and offset

scriber is used when it is required to take measurement from the surface, on which the

gauge is standing. The accuracy and working principle of this gauge are the same as those of

the vernier calipers. Its size is specified by the maximum height that can be measured by it. It

is made of NickelChromium Steel.

Figure 1.12: Vernier Height gauge

1.4 CUTTING TOOLS

1.4.1 Hack Saw

The Hack Saw is used for cutting metal by hand. It consists of a frame, which holds a thin

blade, firmly in position. Hacksaw blade is specified by the number of teeth for centimeter.

Hacksaw blades have a number of teeth ranging from 5 to 15 per centimeter (cm). Blades

having lesser number of teeth per cm are used for cutting soft materials like aluminum, brass

and bronze. Blades having larger number of teeth per centimeter are used for cutting hard

materials like steel and cast Iron.

Hacksaw blades are classified as (i) All hard and (ii) flexible type. The all hard blades aremade of H.S.S, hardened and tempered throughout to retain their cutting edges longer.

These are used to cut hard metals. These blades are hard and brittle and can break easily by

twisting and forcing them into the work while sawing. Flexible blades are made of H.S.S or low

alloy steel but only the teeth are hardened and the rest of the blade is soft and flexible.

These are suitable for use by unskilled or semiskilled persons.


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Figure 1.13: Hacksaw frame with

blade

The teeth of the hacksaw blade are staggered, as shown in figure and known as a set of

teeth. These make slots wider than the blade thickness, preventing the blade fromjamming.

Figure 1.14: Set of

teeth

1.4.2 Chisels

Chisels are used for removing surplus metal or for cutting thin sheets. These tools

are made from 0.9% to 1.0% carbon steel of octagonal or hexagonal section. Chisels are

annealed, hardened and tempered to produce a tough shank and hard cutting edge. Annealing

relieves the internal stresses in a metal. The cutting angle of the chisel for general purpose is

about 60.

Figure 1.15:

Flatchisel


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1.4.3 Twist Drill

Twist drills are used for making holes. These are made of High speed steel. Both

straight and taper shank twist drills are used. The parallel shank twist drill can be held in an

ordinary self centering drill check. The tapper shank twist drill fits into a corresponding

tapered bore provided in the drilling machine spindle.

Figure 1.16: Twistdrills

1.4.4 Taps and Tap wrenches

A tap is a hardened and steel tool, used for cutting internal thread in a drill hole. Hand Taps are

usually supplied in sets of three in each diameter and thread size. Each set consists of a

tapper tap, intermediate tap and plug or bottoming tap. Taps are made of high carbon steel or

highspeedsteel.

Figure 1.17: Taps and tap

wrench


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1.4.5 Dies and dieholders

Dies are the cutting tools used for making external thread. Dies are made either solid

or split type. They are fixed in a die stock for holding and adjusting the die gap. They are made

of Steel or High Carbon Steel.

Figure 1.18: Dies and die

holder

1.4.6 Bench Drilling Machine

Holes are drilled for fastening parts with rivets, bolts or for producing internal

thread. Bench drilling machine is the most versatile machine used in a fitting shop for the

purpose. Twist drills, made of tool steel or high speed steel are used with the drilling machine

for drilling holes.

Following are the stages in drilling work

1. Select the correct size drills, put it into the check and lock it firmly

2. Adjust the speed of the machine to suit the work by changing the belt on the pulleys. Use

high speed for small drills and soft materials and low speed for large diameter drills and hard

materials.

3. Layout of the location of the pole and mark it with a center punch.

4. Hold the work firmly in the vice on the machine table and clamp it directly on to the machine

table.

5. Put on the power, locate the punch mark and apply slight pressure with the Feed Hand.

6. Once Drilling is commenced at the correct location, apply enough pressure and continue

drilling.When drilling steel apply cutting oil at the drilling point.

7. Release the pressure slightly, when the drill point pierces the lower surface of the

metal. This prevents the drill catching and damaging the work or drill.

8. On completion of drilling retrace the drill out of the work and putoffthe power supply.


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Figure 1.19: Bench

drill

1.5 FINISHING TOOLS

1.5.1 Reamers

Reaming is an operation of sizing and finishing a drilled hole, with the help of a

cutting tool called reamer having a number of cutting edges. For this, a hole is first drilled,

the size of which is slightly smaller than the finished size and then a hand reamer or

machine reamer is used for finishing the hole to the correct size.

zHand Reamer is made of High Carbon Steel and has lefthand spiral flutes so that, it is

prevented from screwing into the whole during operation. The Shank end of the reamer is

made straight so that it can be held in a tap wrench. It is operated by hand, with a tap wrench

fitted on the square end of the reamer and with the work piece held in the vice. The body ofthe reamer is given a slight tapper at its working end, for its easy entry into the whole during

operation, it is rotated only in clock wise direction and also while removing it from the whole.

Figure 1.20:

Reamers


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1.5.2 Files

Filing is one of the methods of removing small amounts of material from the surface of

a metal part. A file is hardened steel too, having small parallel rows of cutting edges or teeth on

its surfaces.

On the faces, the teeth are usually diagonal to the edge. One end of the file is shaped

to fit into a wooden handle. The figure shows various parts of a hand file. The hand file isparallel in width and tapering slightly in thickness, towards the tip. It is provided with double

cut teeth. On the faces, single cut on one edge and no teeth on the other edge, which is known

as a safe edge.

Figure 1.21: Parts of a hand

file

Files are classified according to their shape, cutting teeth and pitch or grade of the

teeth. The figure shows the various types of files based on their shape.

Figure 1.22: Single and double cutfiles

Figure 1.23: Types of files


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1.6 MISCELLANEOUS TOOLS

1.6.1 File card

It is a metal brush, used for cleaning the files, to free them from filings, cloggedinbetween the

teeth.

Figure 1.24: File card


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1.6.2 Spirit level

It is used to check the leveling of machines.

1.6.3 BallPeen Hammer

BallPeen Hammers are named, depending upon their shape and material and specified

by their weight. A ball peen hammer has a flat face which is used for general work and a ball

end, particularly used for riveting.

Figure 1.25: Ball peen

hammer

1.6.4 CrossPeen Hammer

It is similar to ball peen hammer, except the shape of the peen. This is used for

chipping, riveting, bending and stretching metals and hammering inside the curves and

shoulders.

1.6.5 StraightPeen Hammer

This is similar to cross peen hammer, but its peen is inline with the hammer handle. It

is used for swaging, riveting in restricted places and stretching metals.

Figure 1.26: Cross peen hammer Figure 1.27: Straight peen hammer


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1.6.6 Screw driver

A screw driver is designed to turn screws. The blade is made of steel and is available in

different lengths and diameters. The grinding of the tip to the correct shape is very

important.

A star screw driver is specially designed to fit the head of star screws. The end of the blade

is fluted instead of flattened. The screw driver is specified by the length of the metal part from

handle to the tip.

Types of screw driver

1.6.7Spanners

A spanner or wrench is a tool for turning nuts and bolts. It is usually made of forged

steel. There are many kinds of spanners. They are named according to the application. The size

of the spanner


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denotes the size of the bolt on which it can work.

1.7 SAFE PRACTICE

Figure 1.28: Spanners

The following are some of the safe and correct work practices in bench work and fitting

shop, with respect to the tools used

1. Keep hands and tools wiped clean and free of dirt, oil and grease. Dry tools are safer touse than slippery tools.

2. Do not carry sharp tools on pockets.

3. Wear leather shoes and not sandals.

4. Dontwear loose clothes.

5. Do no keep working tools at the edge of the table.

6. Position the work piece such that the cut to be made is close to the vice. This practice

prevents springing, saw breakage and personal injury.

7. Apply force only on the forward (cutting) stroke and relieve the force on the return

stroke while sawing and filing.

8. Do not hold the work piece in hand while cutting.

9. Use the file with a properly fitted tight handle.


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10. After filing, remove the burrs from the edges of the work, to prevent cuts to the fingers.

11. Do not use vice as an anvil.


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12. While sawing, keep the blade straight; otherwise it will break

13. Do not use a file without handle.

14. Clean the vice after use.

1.8 MODELS FOR PRACTICE

Prepare the models, as per the dimensions and fits shown in below.

Figure 1.30: Dovetail Fitting Figure 1.31: Vfitting

Figure 1.32: Halfround fitting Figure 1.33: Cross fitting


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Figure 1.34: Drilling and Tapping


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Exercise

1

SquareFiling

Aim

To file the given two Mild Steel pieces in to a square shape of 48 mm side as shown in Figure

FE1

Tools required

Bench vice, set of Files, Steel rule, Trysquare, Vernier caliper, Vernier height gauge, Ballpeenhammer, Scriber, Dot punch, Surface plate, Angle plate and Anvil.

Sequence of operations

1. The dimensions of the given piece are checked with the steel rule.

2. The job is fixed rigidly in a bench vice and the two adjacent sides are filed, using the

rough flat file first and then the smooth flat file such that, the two sides are at right angle.

3. The right angle of the two adjacent sides is checked with the trysquare.

4. Chalk is then applied on the surface of the work piece.

5. The given dimensions are marked by scribing two lines, with reference to the above two

datum sides by using Vernier height gauge, Angle plate and Surface plate.

6. Using the dot punch, dots are punched along the above scribed lines.

7. The two sides are then filed, by fitting the job in the bench vice; followed by checking the

flatness of the surfaces.

As the material removal through filing is relatively less, filing is done instead of sawing.

Result

The square pieces of 48 mm side is thus obtained by filing, as discussed above.


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a. Raw material b. Finishedjob

Figure F

E1:Squarefiling

Exercise

2

VFittin

g

AIM:To make V fit from the given two MS plates and drilling and Tapping as shown

in Figure FE2

Toolsrequire

d


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Bench vice, set of Files, Trysquare, Scriber, Steel rule, Ballpeen hammer, Dot punch, Hacksaw,

Vernier caliper, Surface plate, Angle plate, Vernier height gauge, 5mm drill bit, 3mm drill bit,

M6 tap set with wrench, Anvil and Drilling machine.

Sequence of

operations

1. The burrs in the pieces are removed and the dimensions are checked with

steel rule.

2. Make both pieces surface levels and right angles by fixing in the Vice, use Files for

removing material to get level.

3. With the help of Try square check the right angles and surface

levels.

4. Using Surface plate and Angle plate mark the given two metal pieces as per drawing

with Vernier height gauge.

5. Punch the scribed lines with dot punch and hammer keeping on the Anvil. Punch to

punch give 5 mm gap.

6. Cut excess material wherever necessary with Hacksaw frame with blade, Drill bits

and Taps.

7. The corners and flat surfaces are filed by using square/flat and triangular file to get

the sharp corners.

8. Dimensions are checked by vernier caliper and match the two pieces. Any defect

noticed, are rectified by filing with a smooth file.

9. Care is taken to see that the punched dots are not crossed, which is indicated by the

half of the punch dots left on the pieces.

Resu

lt

The required V fitting is thus obtained, by following the stages, asdescribed above.


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Figure FE2: VFitting


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HOUSE WIRING

DIFFERENT SYSTEMS OF WIRING:

The various systems of domestic and industrial wiring are:

(1) Cleat wiring (2) casing capping (3) CTS wiring

(4) Metal sheeted Wiring (5) conduit Wiring

Before deciding the type of wiring to be used at a particular site, the following

points should be considered:

a. Durability: the wire selected should be able the to withstand for a long

period against weather changes.

b. Safety: safety is the foremost point to be kept in view while making

Decision of the systems of wiring. It may not prove to be risky. At places

which are not free from fire danger conduit wiring is preferred.

c. Cost: the cost of wiring installation is one of the main points to be

considered. The system chosen should be economical and within the

means of the individual.

d. Appearance: wiring appearance has its own effect. Architectural

Beauty should be kept in view.

1) CLENT WIRING: In this systems V.I.R (Vulcanized India rubber) wire

used in porcelain cleats. The cleats are of three types, having one, two or

three grooves so as to receive one two or three wires. They are made in

two halves. One is grooved to receive the wire the other is put over it and

the whole is fixed on the wall. The system of installation is cheap and its

most suitable for temporary wiring. It can be easily installed and also

removed quickly when not require.


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2) WOOD CASING CAPPING: The system of wiring recommended to be made of

well seasoned teak wood or any other suitable hard wood. It should be free from

knots shakes or any other defect. The casing has usually two grooves to carry

wires. At the top it is covered by a strip known as the capping. The width of the

capping to show position of wires so that the screws may not be driven through

wrong position. Wood gutties are fixed on the wall separated by a distance of not

more than one meter. Round porcelain disc insulator are used between the wood

gutties and casting. The fixing is done with countersunk scores into the gutties.

The capping is screwed over 15cm for all sized up to 6cm. width casings.

3) CTS WIRING: CTS cable tyre sheathed wires are available in single

twin or three cores with a circulars or oval shape. The cable is free the

effects of moisture, acids alkalies and climatic variations. It can be

exposed to sun. The cable can be buried under / sasonary work but is

usually laid over wood battens. The system is even suitable for places

where chemical fumes are present.

4) METAL SHEATHED WIRING: The wire consist of rubber insulated

conductor over which as heath of lead aluminum alloy is provided

externally. This covering provides protection to the cable from

mechanical injury. In residential buildings they are run over wooden

battens. The sheathed should be earthed otherwise electrolytic action may

take place to the leakage of current and there by deteriorate the covering


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moreover earthling prevents the metal covering from becoming alive.

These cables are not suitable for places where chemical corrosion may

rise. They effect on the open ends of cable are give; these cable are more

costly than CTS ones.

The following points should be noted when installing metal sheathed wiring.

1. Metal clips and Saddles used to support the cable should be placed

40cm apart.

2. The support used should not be of such a material as to cause

chemical action with the sheaths.

3. The icas sheath should be run over a damp place.

4. The cable should be run over the damp place.

5. The cable should be run in conduits when crossing the floor or wall.

6.Sharp bends should be avoided.

7. Conduit wiring: workshop and public building this is the best and most

Desirable system of wiring it provides mechanical protection and

safety against fire. They can be supported over the wall by saddles and

pipe hooks.

Care & Maintenance of Tools:

1. PLIERS: 1) Do not cut steel wires and other hard

substances


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2. SCREW DRIVER:

a) The edge should not be too sharp

b) At must fit in the slot of the screw head

c) Do not use it as hammer or chisel

3. POWER:

a) Keep it well sharpened

b) Do not use it on metals

4. GIMLET:

a) It should be kept straight while holes otherwise the screwed portion may

damage.

5. FIRMER CHISEL:


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a) Always strike the chisel with mallet

b) Grind it on the water stone and shapen it on the oil stone

c) Do not use it at place where nails are driven in

6. COLD CHISEL:

a) The edge must be properly maintained

b) There should be no trace of oily substance


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7. TENON SAW OR HAND X SAW:

a) Keep the teeth sharp with triangular file.

b) Protect from must

c) When not in use apply grease

d) The handle should not be loose

7. DRILLING MACHINE:

a) Keep the machine always clean and lubricants the parts specially the

gears.

b) Drill bit should be properly fixed in the jaws of the machine


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c) Keep it perpendicular to the place of the job while making loose.

d) If taper hole is to be made, first make a guide hole with a small bit and

then use a bit of the proper size.

9. SOLDERING IRON:

a) Before soldering an object first time its bit.

b) Clean the rust or dirt with sand paper before applying the soldering iron

c) Soldering should not be cover heated

10. VICE:

a) Vice should not be used as an anvil.

b) It should not be tightened excessively

c) Clean regularly after use.


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11. WIRING TOOLS:

1. COMBINATION PLIER: Plier is used for cutting and twisting the

wires. They are specified in length and the range is 15, 20, 25, or 30 cm.

either they are insulated or un insulated. Insulated Plier is particular used

on live wires because the insulation gives protection from shocks.

2. SIDE CUTTING PLIER: It is used for cutting wires and happening the

insulation from the . it is widely used for winding works, radio assembling

and other delicate instruments.

3. ONG NOSE PLIER: It is used for working in space for holding

lightening and loosening small nuts.

4. SCREW DRIVERS: Screwdrivers of different sizes are used for different types

of jobs. They are used for taking out or driving slotted heat screws by


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turning them. The size is measured by its blades. A good driver has a

hardened and tempered egde. The edge should not be ground to suit

different screw heads.

5. POKER: it is a pointed tool with flat sides and used for making pibt

holes for screws in wood casing boxes etc.

6. GIMLET: It is used for making holes in wooden articles. They are of

different length and different diameters. The diameters various steps of

3mm from 6mm to 25mm.

PINCER: It is used to extract nail and cut conductors.

7. HAND DRILLING MACHINE: It is used for making holes in metal

works. Chucks to take drill bits up to 9.5mm. Serve the purpose of an

Electrician.

8. SOLDERING IRON: Electric soldering iron is very solder small joints,

terminals, etc., for heavy duty work an iron of high wattage is used such as

125 or 250 watts.


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9. STANDARD WIRE GAUGE:A circular plate of steel has a number of slots on

its circumference. The numbers are marked on each slot. Holes are

provided at the end slot for moving the wire easily. To find the gauge of a

wire, the particular slit is found by trail into which a bare wire just slideswithout being damaged. The number stamped opposite to the number of

the gauge required.

10.KNIFE: it is folding steel knife, which is very useful for cleaning wires. It

should not be used for cutting wires.

11.BRAWL PLUG TOOL: The tool has bits of metal suitable for the job. Usually

they are made of steel the tool bits are numbered according to the size of

plugs used. Their importance lies in wiring concrete and stonewalls. Holes

are made on the walls of sufficient depth and fires plugs are inserted in

them. The material to beheld in position is placed on the plug to expand

and grip the wall. While using

the tool, it should be rotated slowly after each hammering moreover it

Should not be used on the material.

ACCESSORIES:

1. ICDP (Iron Clad Double Pole) switch 15 Amps.

2. SPT (Single polo tumbler) switch 5 Amps.

3. 2-way tuber x switch 5 Amps.

4. Intermediate switch 5 Amps.

5. Batton holder Brass or (Bakelite)

6. Pendant holder (Brass or Bakelite)

7. Slanting or angle holder brass


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8. Wall bracket

9. Batton holder MC (Miniature cup )type

10. Wall socket 2 pin 5 Amps.

11. Wall socket 3 Pin 5 Amps

12. 2 Pin plug switch combined

13. Ceiling rose 5 Amps

14. 3 Plate ceiling rose 5 Amps.

15. Junction box or cut 5 Amps.

16. Electric bell 230 volts & bell push switch.

17. Bed room transformer 230 volts. 13.5.8 volts.

18. SWG (Standard wire gauge) used for expressing the size of wires.

19. Kt. Kat 15 Amps.

20. VIR (Vulcanized Indian rubber) wire 1/18

21. CTS (Cable tyre sheathed ) wire 1/16

22. Flexible wire plastic or silk core.

23. Wooden screws 60mm, 50mm, and No.8 for rectangular and round blocks.

24. Wooden screws 30mm no 8 for porcelain cleats 2 ways & 3 ways.

25. Wooden screws 20mm no 5 for tumbles switches ceiling rose cut out power

plug and repair.

26. Wooden screw 12 mm, no 4 for batton holder

27. 2-pin socket wall bracket transformers and wood capping

28. Porcelain cleats 2way and 3 way


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29. Wood casing and capping

30. Link clips 45mm, 35,, and 30mm etc.

31. Nails 12mm no 17 for link clips.

32. Bare copper wires, no. 14 SWG

1.EARTHING: In an electric circuit, power passes from positive to the

negative terminal. The Earth is the biggest negative terminal. The tendency

for current is to pass to the earth if a suitable contact/conductor is

available. In an electric circuit ,if there is any gap due to improper

connection, (the air being a poor conductor), current will not flow in

the circuit. Bur of such a circuit having positive potential is touched by a

human being, current will pass through the body into the earth making him

a part of the circuit. Ear thing 2x2x4 for one normal houseHuman body

gets electric shock proportional to voltage. Higher the voltage, higher the

damage. In many countries like US, Canada etc the domestic voltage is only

110V against the 220 V being used in India. So the danger of shock is prevented inthose countries whereas we have the pro0blem, due to 220 V supply voltage. Ear

thing is a safety device to run an electric conductor in parallel to the circuit

connecting body of the equipment and a third point to the earth. By this in case of

any open circuit accidentally, the current will travel through the earth wire to

earth causing no damage t the person becoming a part of the circuit. It is legally

necessary for all machines and other equipment used in factories.

DEMONSTRATION: Ear thing system/3-pin plug/earth connection

2.FUSE :Fuse is a device to protect electrical equipment against

overloading of its components due to short circuits etc. Every electrical


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equipment is designed to with stand certain current rating. If the current

supplied is higher, it will damage the equipment. To prevent such damage

a thin wire of low melting point-alloy of optimum current carrying

capacity is provided near the main switch in the circuit. If due to any short

circuit or voltage fluctuation, the current in the circuit exceeds the limit, the

fuse-wire gets melted (due to low melting point-alloy with which it is made

and the thin dia)breaking the circuit. This saves the electric equipment from

getting spoiled by continuous exposure to such high current.

Precautions: Do not use thick-wire/copper wire for fuse as it allows excess current

into the circuit and causes heavy damage permanently to equipment.

DEMONSTRATION: Types of fuse wire/fuse-holder / cartridge / fuse / replacing a

fuse.

SAFETY PRECAUTIONS FOR AVOIDING ELECTRICAL ACCIDENTS.

IMPORTANT: Electric shock are easily received and avoided. The risk is not always

apparent, be careful. Take no chance.

1. Always switch off the main switch before replacing a blown fuse.

2. Always use correct size of fuse, while replacing blown fuse.


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3. Always maintain earth connection in satisfactory condition, safety

depends upon good earthling.

4. Beware of live-wires or conductors bare or insulated.

5. Before replaying a lamp or handling a table fan be sure that he switch is

in OFF position.

6.

Before switching on current to any portable equipment, make sure thatit is properly earthed and insulation is sound.

7. Be sure that all the connections are tight.

8. Before working on inductive circuits or cable discharge them (through

short circuit) or earth.

9. Dont forget to put on safety belt before starting work on ground level

or pole.

10.Never disconnect a plug point by pulling the flexible wire.

11.Never temper unnecessary with any electrical apparatus unless you are

authorized to handle it.12.Never touch an over head line unless you sure that it is dead and

properly earthed.

13.Never energies a line unless you are sure that all is clean and there is no

one working on that line.

14.Never temper with electric prospective or inter-locking gearing unless

you are specially authorized for them, taking all precautious. The advices

are for your safety only.

15.While handling any portable appliances (table fan etc.) see that it is

disconnected from supply, switching OFF may not enough, leakage ofinsulation can give you a serious shock.

16.While working on an motor/Generator (Rotating Machine) make it sure

that no one can put it to ON position without your permission.

17.When cells are being charged in a room, always maintain good

ventilation. Never bring a naked light near a battery.

18.Do not bring a naked light near a battery, Smoking is also prohibited in

the battery room.


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19.Rubber mattresses are placed in front of electrical panels and switch

boards.

20.Do not tie the wire with electric pole.

21.In case of fire:

i) Do not throw water on equipment. It will be very harmful

to you, because water is good conductor of electricity.

ii) Disconnect the supply immediately.

iii)Do not use a fire extinguisher on electricity unless it is suitable for

that purpose.

22.Use portable insulated hand lamp for testing purpose.


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HOUSE WIRING

Excersice-1

AIM: To control one lamp independently with one S.P.T. switch in conduit wiring

according to the given diagram.

ROUTE DIAGRAM CIRCUIT DIAGRAM


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S.No. Item Description Quantity Size

1 P.V.C. Pipe 3 Nos. 51 cms

2 Teak wood round block 7 x 4 2 Nos.

3 Wire 1/18 S.WAG P.V.C. 180 cms

4 Brass button holder 5A 1 No.

5 Tumbler switch one way 5A 1 No.

6 P.V.C. 3 way Box 1 No.

7 Saddle 3 Nos.

8

Wooden Screws:

1)

50mm No-8 2 Nos.

2) 20mm No.5 2Nos.

3) 12mm No.4 2Nos.


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TOOLS REQUIRED:

S.No. Item Description

1 Tenon Saw size 250 mm

2 Screw driver size 250 mm 828

3 Insulated Cutting Piler

4 Screw driver size 200 mm 937

5 Firmer Chisel size 12 mm

6 Screw Driver size 150 mm 912

7 Drill Machine

8 Ball Pen Hammer 0.25 kg.

9 Drill Bits 6mm & 4mm

10 Poker

11 Knife or Insulation remover.

PROCEDURE:

1) Draw the route diagram of the wiring on the board with chalk.

2) Cut the required length of P.V.C. pipe and fix as per route diagram and by

help of saddle.

3) Cut the P.V.C. wire of the required length and fix in the P.V.C. Pipe

according to circuit diagram.4) Drill holes around block for wires and fix them in them to the board.

5) Fix the holder on one of the round blocks and the switch on the other.

6) Complete the wiring as per the circuit diagram and check it with mugger

before giving the supply.


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PRECAUTIONS:

1) The tools should be used carefully.

2) All the connections should be tight.

HOUSE WIRING

Excersice-2

AIM: make P.V.C. conduit wiring connection to control one lamp with S.P.T. switch

and one 2 pin socket point independently according to given route diagram.

ROUTE DIAGRAM

Circuit Diagram


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HOUSE WIRING

Exercise-3

AIM: Make conduit connection in to control one lamp from the differentplaces with two different places with two different switches according to

given route diagram ( Staircase Wiring).

ROUTE DIAGRAM


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CIRCUIT DIAGRAM

PROCEDURE:

1) Draw the route diagram of the wiring on the board with chalk.2) Cut the required length of P.V.C. pipe and fix as per route diagram and by

help of saddle.


according to circuit diagram.

4) Drill holes around block for wires and fix them in them to the board.

5) Fix the holder on one of the round blocks and the switch on the other.

Complete the wiring as per the circuit diagram and check it with mugger


PRECAUTIONS:




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HOUSE WIRING

Exercise-4(a)

AIM: To Control a bell with bell switch in conduit wiring as per the route wiring.

Route Diagram

Circuit Diagram


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PROCEDURE:

1) Draw the route diagram of the wiring on the board with chalk.

2) Cut the required length of P.V.C. pipe and fix as per route diagram and by

help of saddle.


according to circuit diagram.

4) Drill holes around block for wires and fix them in them to the board.

5) Fix the bell on one of the round blocks and the switch on the other.

Complete the wiring as per the circuit diagram and check it with mugger


PRECAUTIONS:



Earthing ((Exercise-4(b))


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The process of connecting metallic bodies of all the electrical apparatus and

equipment to huge mass of earth by a wire having negligible resistance is called

Earthing

Purpose of Earthing

To save human life from danger of electrical shock or death by blowing a

fuse i.e. To provide an alternative path for the fault current to flow so that

it will not endanger the user

To protect buildings, machinery & appliances under fault conditions ie. To

ensure that all exposed conductive parts do not reach a dangerous

potential.

To provide safe path to dissipate lightning and short circuit currents.

To provide stable platform for operation of sensitive electronic

equipments i.e. To maintain the voltage at any part of an electrical system

at a known value so as to prevent over current or excessive voltage on the

appliances or equipment .

To provide protection against static electricity from friction

Concept of Earthing Systems

All the people living or working in residential, commercial and industrial

installations, particularly the operators and personnel who are in close operation

and contact with electrical systems and machineries, should essentially be

protected against possible electrification. To achieve this protection, earthing

system of an installation is defined,

designed and installed according to the standard requirements..


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PLUMBING TOOLS

INTRODUCTION FOR TOOLS OF PLUMBING:Following tools are used in the common

plumbing working up to medium size (10 cm / 100 mm) pipes.

1) Hacksaw2) Pipe Cutter

3) Pipe Vice

4) Pipe Bending Machine5) Threading die

6) Ratcher type die holder

7) Pipe wrench

8) Chain-wrench9) Adjustable wrench

10) Water pump pliers

11) Set the common spanners and ring spanners

1) HACKSAW: It is used for cutting of pipes. Figure 1 shows a hacksaw commonly used, it

essentially consists of a frame, Handle, Prongs, tightening screw and nut. The blade is fixedin position and tightened by means of the tightening screws.

2) PIPE CUTTING: A pipe cutting is used to cut off the pipes. It has a handle have the lengthto a suitable leverage, front position is like the letter C, Three rollers are fixed in it. The

shape of the rollers is convex on both sides. They are made of alloy steel hardened and

tempered. They rotate themselves with friction while moving around the pipe.

3) PIPE VICE:It is a device used to hold the pipe firmly while doing the operations of cuttingthreading etc., and while fixing or removing the couplings, the jaws have vee shaped grooves

or steps and they grip the pipe firmly at four corners.


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4) PIPE BENGDING MACHINE:Figure, shows a pipe bending machine, hydraulicallyoperated, It essentially consists of two adjustable bending blocks. The third daily block is

pressed by means of hydraulic jack and bends the pipes according to the requirements.

5) THREADING DIE:This is a cutting tool up of HSS (High Speed Steel) Material and is

used for cutting external threads on pipes. Dies are available in different sizes and each one

will form thread of that specify size i.e., BSP die set can produce BSP threads only.Dies are fixed in die holder and pipe to be threaded is fixed in pipe vice. Dies are inserted on

to the pipe and die holder is gradually rotated completely till the threads are formed on the

pipe. It is required to check with the help of socket whether thread is completing formed ornot. Die holder has to be rotated in opposite direction for withdrawing the die sets form the

pipe.

6) RATCHET TYPE DIE HOLDER:The ordinary die holder is not suitable for threading the

pipes which are fixed in their position and die holder cannot be completely rotated due to

certain obstructions like wall, other pipes etc in such cases, ratchet type die holder is used. Itcan be rotated in the regular direction partially and dies also rotate. It can be rotated in

opposite direction in which ratchet slips and only holder is rotated but not die sets. Again it


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can be rotated in regular direction for further threading, like wire thread is completed. Forwithdrawing die sets, ratchet position is reversed so that it rotates the die set in the opposite

direction and slips in the regular direction. Thus die sets are withdrawn from the pipe. This is

suitable for cutting the threads where complete & rotation of the die holder is not possible.

7) PIPE WRENCH: Figure shows a pipe wrench commonly used for tightening andunscrewing of the pipe up to 7 cm diameter pipes. These pipes wrenches are manufactured

from 50 to 60 cm length. The teeth are provided on the jaws to hold the pipe in position and

prevent its slipping while tightening.

8) CHAIN WRENCH:The front portion of the chain wrench is like a triangle and handle is

fixed with it having a chain also. After fixing the chain around the pipe, the chain end is

inserted in a box for locking with a pin, It holds the pipe firmly and it is fit for rotation on

either ways.

9) ADJUSTABLE WRENCH:Figure shows an adjustable wrench pump plier. It is used for

screwing and unscrewing of small diameter pipes. It can also be used in tightening of nuts of

bolts, fixing of small taps, valves, etc, in the pipe lines.

10)WATER PUMP PILER:Figure shows a water pump plier. It is used in house plumbing

work. It is the most tool used in the plumbing work.


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11)SET COMMON SPANNERS AND RING SPANNERS:Set of ring spanners and common

spanners are required in the plumbing work for various tightening works of cocks, valves,

etc.

PART FOR PIPE & JOINTS

G.I. (GALVANIZED IRON) PIPES:Pipes are used for carrying fluids such as water, steam,

gas, oil, etc., from one place to another. As pipes are made in standard lengths, and desiredlength of a pipe may be obtained by joining them. The type of joint used depends upon the

material of the pipe and purpose for which it is used.

Generally, pipes are made of cast iron, wrought, iron, steel, brass or copper. The material

selection is based on the nature of the fluid to be conveyed, viz., pressure, temperature, chemicalproperties, etc. Now a days PVC (Polyvinyl chloride)pipes are extensively used ease for various

purpose.

1) COUPLING: It is a hollow piece having full of threads in the inner side. It is used to

join two pipes of the same diameter on a straight line, on any length of pipes.

COUPLING

2) ELBOW:It is used for changing the direction at right angle by square or round. It hasinner threads in the both ends to a short length. The two pipes are screwed in it is any

length.


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ELBOW

3) TEE:(T) It is used to make a branch right angle to the main line. It accommodates three

pipes at any length.

TEE

4) CROSS (T): It is used to speed over the main line on other two opposite direction at

right angle to one another. It accommodates four pipes at any length.

CROSS (T)

5) REDUCER COUPLING:It is used to extend the length in straight line jointing the twopipes in different diameters in any length.

REDUCER COUPLING


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6) PLUG:It is used to block up the pipe on one end. It has a square neck for a spanner torotate for tightening or loosening.

PLUG7) UNION:It consists of three parts. After tightening the pipes on both ends the octogen nut

is tightened. It is used in the pipe line only to separate the connections without disturbing

the pipe line.

UNION8) FLANGE: It is used for joining the two ends of pipes with bolds and nuts, either in

vertical or horizontal positions it is screwed at one end of the pipe.

FLAN

GE9) GLOBE VALVE:Where there are many branches, it is fitted for controlling the division

separately. The fluid may be stopped or allowed in any quantity according to the rotation.


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GLOBE VALVE


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EXPLANATION

PVC SWR Pipes (Polyvinyl chloride,Soil Waste & Rain pipes or(rigid PVC))& Fittings

have many Advantages over traditional Cement, Asbestos, Cast-Iran (C.I.) Pipes &

Fittings.

Durability & Weather Proof:

PVC SWR (Polyvinyl chloride, Soil, Waste & Rain' or (rigid PVC)) Pipes are made fromvirgin PVC Material thus resistant to extremes weather conditions, toxic chemicals unlike C.I.

Pipes they are rust & corrosion proof. Cement & Asbestos pipes, have high thermal sensitivity,

which leads to crack & breaking of the pipes PVC SWR Pipes can with stand extreme variations

in temperature.

Dimensional Stability:

PVC SWR(Polyvinyl chloride Soil, Waste & Rain' or (rigid PVC)) Pipes & fittings have

dimensional stability, these are not effected due to external pressure of support, clamps andfixtures. This also makes possible leakage proof system.

Great Strength & Light Weight:PVC SWR (Polyvinyl chloride, Soil, Waste & Rain' or (rigid PVC)) Pipes are comparatively

lighter I weight, yet they can with stand high pressure. They can be easily transported, handled

fixed and maintained.

Highly Efficient:The Smooth & even surface of PVC SWR Pipe (Polyvinyl chloride, Soil, Waste & Rain' orPVC

(rigid PVC)s provides free flow of water, which improves the efficiency of the system.

Resistance:

PVC SWR Pipes are resistant to Oils, Heat and Fire, Fats, Alcohol, AromaticFree Patrols andare more reliable as there is no growth of Fungus, Bacteria, and Termites.

Economical:PVC SWR Pipes & Fittings prove to be economical on all fronts right from basic cost,

transportation, fixing & maintenance.

Applications:Homes, Offices, H

Workshop Manual 2016

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Transcript of Workshop Manual 2016