Fitting & measurment Tools

FITTING TOOLS FITTING TOOLS

MadanMadanMadanMadan LalLalLalLal ChandravanshiChandravanshiChandravanshiChandravanshi

Assistant Professor Assistant Professor Assistant Professor Assistant Professor

Department of Mechanical Engineering Department of Mechanical Engineering Department of Mechanical Engineering Department of Mechanical Engineering

I S M I S M I S M I S M DhanbadDhanbadDhanbadDhanbad

FITTING SHOP TOOLS ARE CLASSIFIED AS

BELOW

� Clamping Tools.

� Measuring and Marking Tools.

� Cutting Tools.

� Striking Tools.

� Drilling Tools.

� Threading Tools.

CLAMPING

TOOLS

� The vice is the most common tool used for

clamping or holding work

BENCH VICEBENCH VICEBENCH VICEBENCH VICE

� It is firmly fixed to the bench with the help of nuts and bolts. It consists of a cast iron and cast iron jaws. Two jaw plates are fitted on both the jaws. The holding surface of the plates is knurled in order to increase the gripping. Jaw plates are made up of carbon steel are wear resistant. One jaw is fixed to the body and the second slides on a square threaded screw with the help of a handle.

� The jaws are opened up to required length, job is placed in the two jaws and is fully tightened with the help of handle. Handle is used to move the movable jaw.

PRECAUTIONS ASSOCIATED WITH THE USE OF

VICES

� Vices should be kept clean and free from dust

and metal chips, using a brush.

� The vice should never be used as an anvil.

� If should be occasionally oiled.

� The serrated jaws should be covered with soft

metal clamps when finished work is held.

� Don't use hammer to move the handle.

HAND HAND HAND HAND VICEVICEVICEVICE

� For gripping very small work (objects) a hand vice is employed. These are made in different shapes and ides depending upon the job. A commonly used consists of the two steel legs hinged together at the bottom. A spring provided between two legs helps in opening out by its pressure. The jaws are adjusted from a flange nut. The vice is held in a one hand and the other hand performs the required operation.

PIN PIN PIN PIN VICEVICEVICEVICE

� It is used to hold wire or small diameter rods. It

consists Pivot of a self-centered three jaw

chuck made up of a tool steel. The work is

gripped between the jaw of the chuck by

rotating the handle.

Fig.3. Pin Vice.

PIPE PIPE PIPE PIPE VICEVICEVICEVICE

� It is used to hold pipes,

shafts or round jobs. It

consists of a vertical screw

with square treads. A handle

is attached on the top of the

screw to move the movable

jaw, which is fixed, on the

lower end of the screw. It

grips the work at four points.

BLOCK BLOCK BLOCK BLOCK WITH WITH WITH WITH U U U U CLAMPCLAMPCLAMPCLAMP

� In V Block, V grooves are provided to hold the round

objects longitudinally. The screw clamp applies the

holding pressure. When the handle is rotated there

is movement in the screw.

MEASURING INSTRUMENT AND

MARKING TOOLS

MEASUREMENT

� Measurement is the comparison of anunknown dimension to a known standard.

� Good measuring instruments were a key to highvolume production. Without them, parts couldnot be built accurately enough to beinterchangeable. Each assembly had to behand fitted together.

� Today, measuring tools are essential for mostmachining operations from initial part layout tofinal inspection.

CLASSIFICATION OF MEASURING INSTRUMENTS

� Precision instrument

� Ability to measure within the accuracy of 0.01 mm

or more

� Non-precision Instrument

� Limited to the measurement of parts to a visible

line graduation on the instrument (ex Scale)


� Direct measuring Instruments

�Determine the actual dimension and size of a work

piece

� Indirect measuring Instruments (comparison

instruments)

� Transfer the measurement from the work piece to

the direct measuring instrument, then comparison

is made.


� Line measuring devices

�measurement along the length (steel rule)

� End measuring devices

�Measurement between the two ends (vernier

caliper)

PRINCIPAL MEASURING INSTRUMENTS

� Linear Measurements

� Steel rule

� Calipers

� Divider

� Depth gauge

� Micrometers

� Vernier caliper

� Height gauge

� Slip gauge

� Comparator

� Angular Measurements

� Protractors

� Adjustable bevel

� Engineering's’ square

� Bevel protractor

� Dividing head

� Sine bar

� Angle gauge

� Clinometers

� Autocollimators

TRY SQUARE

� It is used for checking squareness of two

surfaces. It consists of a blade made up of

steel, which is attached to a base at 90 degree.

The base is made up of cast iron or steel. It is

also used to mark the right angles and

measuring straightness of surfaces. Never use

try square as a hammer.

Fig. 6

SURFACE SURFACE SURFACE SURFACE PLATEPLATEPLATEPLATE

� It is used for testing the flatness, trueness of the

surfaces. It is made up of cast iron graphite. Its upper

face is planed to form a very smooth surface. It is also

used in scribing While not in use, it should be covered

with a wooden cover.

BEVEL PROTRACTORBEVEL PROTRACTORBEVEL PROTRACTORBEVEL PROTRACTOR

� It consists of a steel dial divided into 360

divisions. The dial can be rotated around the

centre. The value of any angle can be marked

or measured by the straight edge. Straight edge

can be slide along the length.

COMBINATION SETCOMBINATION SETCOMBINATION SETCOMBINATION SET

� It is a multipurpose instrument that can be used as

protector, a level, a centre square and a try square.

CENTRE SQUARECENTRE SQUARECENTRE SQUARECENTRE SQUARE

� It is used to find the centre of the round jobs.

It consists of a straight edge and two arms.

For finding out the centre, the round job is

placed between two arms.

SCRIBER AND SURFACE GAUGESCRIBER AND SURFACE GAUGESCRIBER AND SURFACE GAUGESCRIBER AND SURFACE GAUGE

� It consists of a cast iron base on the centre of

which a steel rod is fixed vertically. Scriber is made

up of high carbon steel and is hardened from the

front edge. It is used for locating the centers round

bars or for marking of the lines.

UNIVERSAL MARKING SURFACE GAUGEUNIVERSAL MARKING SURFACE GAUGEUNIVERSAL MARKING SURFACE GAUGEUNIVERSAL MARKING SURFACE GAUGE

� It consists of a cast iron base, a spindle and a scriber. The spindle can be set at any angle. Scriber can also be set at any angle and at any height from the base maximum up-to the length of spindle. It is used for marking purposes.

PRINCIPAL MEASURING INSTRUMENTS

� Surface Measurement

�Straight edge

�Surface plate

�Surface gauge

�Optical gauge

�Profilometer

PUNCHESPUNCHESPUNCHESPUNCHES� Punches are used for marking purposes. Dot punches are

used for marking dotted line and centre punch is used to

mark the centre of hole before drilling. Punches are

made up of high carbon steel or high speed steels. One

end is sharpened. Hammering is done on the second end

while working. For dot punch, angle of the punching end

is 60 degree while in centre punch.

STEEL RULESTEEL RULESTEEL RULESTEEL RULE

� These are made up of stainless steel and are

available in many sizes ranging from ½ ft to 2

ft. These are marked in inches or millimetres.

All the faces are machined true. The edges of

rule should be protected from rough handling.

VERNIERVERNIERVERNIERVERNIER CALIPERCALIPERCALIPERCALIPER

VERNIERVERNIERVERNIERVERNIER CALIPERCALIPERCALIPERCALIPER� It is a precision instrument used for measuring heights, diameters

and depths. It can used for measuring external and internal dimensions.

� It consist of a beam, carrying the main scale, inside and outside measuring jaws, a depth gauge bar and an adjustable Vernier head which can be moved along the beam. Fine adjustment done with the help of a screw. Both the heads are provided with locking screw to lock at any desired position.

� The dimension is measured by the main scale reading and by the vernier scale division.

� Dimension = Main scale reading + Least count x Dimension = Main scale reading + Least count x Dimension = Main scale reading + Least count x Dimension = Main scale reading + Least count x VernierVernierVernierVernier scale reading scale reading scale reading scale reading

� Least count. It is the minimum reading that an instrument can measure.Least count. It is the minimum reading that an instrument can measure.Least count. It is the minimum reading that an instrument can measure.Least count. It is the minimum reading that an instrument can measure.

ELECTRONIC VERNIER CALIPERS

Electronic calipers

� Electronic calipers are relatively expensive

compared to the standard vernier style.

� They are quite accurate, quick, and easier to

read, however.

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CLASSES OF VERNIER CALIPERS

32

DIGITAL ELECTRONIC CALIPERS

� These have an electronic readout rather than a

vernier scale.

� Typically an electronic caliper will have three

buttons, an on/off button, an English/Metric

button, and a Zero button.

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DIGITAL ELECTRONIC CALIPERS

� The procedure of using an electronic caliper is:

�Turn the caliper on.

�Select English (inches) or Metric (millimeters)

reading mode.

�Close the caliper jaws and press the Zero

button.

�Measure the desired object and read the

digital readout.

MICROMETERMICROMETERMICROMETERMICROMETER

MICROMETERMICROMETERMICROMETERMICROMETER

� It is used for measuring diameter or thickness of any job.

� It is more precise than Vernier Caliper.

� It consists of a hook type frame. A hard anvil is screwed on one end, On the second arid, a spindle moves to and fro carrying another small anvil on its end.

� The sleeve on the spindle graduated and is called main scale. The Vernier scale is provided on the thimble that is around the spindle.

� The gap between the two anvils is adjusted by moving (rotating) the thimble.

� Ratchet Ratchet Ratchet Ratchet is provided on the side of the spindle to apply fine pressure. Lock nut is provided to lock any desired position.

LEAST COUNTLEAST COUNTLEAST COUNTLEAST COUNT

� In one complete turn of the thimble distance In one complete turn of the thimble distance In one complete turn of the thimble distance In one complete turn of the thimble distance

covered on main scale covered on main scale covered on main scale covered on main scale

� = 0.5 mm = pitch

� Divisions on Divisions on Divisions on Divisions on VernierVernierVernierVernier scale scale scale scale (i.e. on thimble) = 50

� PitchPitchPitchPitch = 0.5 mm

� Least count Least count Least count Least count = Pitch/Division on Vernier scale

� = 0.5/50 = 0.01 mm

� Final reading Final reading Final reading Final reading = Main divisions x 1 mm + sub

division on main scale x 0.5 mm + least Count x

division on Vernier scale.

DIAL INDICATORDIAL INDICATORDIAL INDICATORDIAL INDICATOR

DIAL INDICATORDIAL INDICATORDIAL INDICATORDIAL INDICATOR

� It is a round gauge in which a pointer moves over a graduated scale.

� The movement magnified through links. When there is movement in plunger pin, this movement is magnified various mechanical links and shown by the rotaterymotion of the pointer.

� A nut is also prove on the head for zero adjustment. End of the plunger touches with the job while measuring.

� Complete revolution of the main pointer corresponds to 1 mm that is divided into 100 parts. Total no. of revolution of main pointer is indicated by small pointer. It is used to check the run out modality of jobs.

DIVIDERSDIVIDERSDIVIDERSDIVIDERS

� These are made up of steel.

Dividers have two legs

having sharp feet.

� These are hinged at the top.

It is used for marking arcs,

dividing a line or transferring

a dimension.

CALIPER CALIPER CALIPER CALIPER

� These are generally used to measure the inside

or outside diameters. Different types are :

� Outside CaliperOutside CaliperOutside CaliperOutside Caliper. It is used to measure the

outside dimensions.

� Inside CaliperInside CaliperInside CaliperInside Caliper, it is used to measure the inside

dimensions.

� Spring CaliperSpring CaliperSpring CaliperSpring Caliper. Spring is provided to apply the

pressure and lock nut is provided to lock any

desired position.

CALIPER CALIPER CALIPER CALIPER

OUTSIDE CALIPER

OUTSIDE CALIPER

� Spring-loaded OD Calipers are an inexpensivealternative to vernier calipers.

� They do have limitations - primarily in accuracy andversatility.

� Advantages other than cost may be in the increasedmeasuring capacity or range, and heat tolerancewhen making rough measurements.

� The horizontal threaded rod contains a thumbwheelfor adjusting the width of the two measuring arms.

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INSIDE CALIPER

INSIDE CALIPER

� Spring-loaded ID Calipers have the same

features and limitations of the OD Calipers. The

difference is in the shape/orientation of the

measuring arms allowing access to the inside

of the object.

Measurement 46

GAUGESGAUGESGAUGESGAUGES


� Depth Gauge.Depth Gauge.Depth Gauge.Depth Gauge. It consists of a stainless steel head and a beam. The head slides the beam

and can be tightened with the help of a screw. The beam is graduated in' or millimetres.

� Feeler Gauge.Feeler Gauge.Feeler Gauge.Feeler Gauge. It is used to check the gap between two mating parts. It consists number of

metal leaves. These have different thickness (marked on each leave fastened together in

a small holder. The material of the leaves is stainless steel.

� Radius Gauge.Radius Gauge.Radius Gauge.Radius Gauge. It is just like a feeler gauge. Every leaf has different radius. It is of two

types—internal or external. It is used to check the radius of outer and inner surfaces. The

radius is marked on each leave and is fastened together in a small holder.

� Thread GaugeThread GaugeThread GaugeThread Gauge. It is used to check the pitch of threads. It consists of a number of leaves.

On every leaf cuts art provided to check the threads on the job. The thread on the leave

should be properly fit on the thread to be measured. The material of the leaf is stainless

steel and is assembled in a holder.

� Wire Gauge.Wire Gauge.Wire Gauge.Wire Gauge. This gauge is used to check the diameter of wires. It is

made up of a steel sheet disc.

� VernierVernierVernierVernier Height Gauge.Height Gauge.Height Gauge.Height Gauge. It is used for measuring the height of the

parts or scribing lines at height or for marking purposes.

� It consists of a vertical bar mounted on a base.

� A sliding headA sliding headA sliding headA sliding head with pointer is carried on the vertical rectangular

part (bar). The bar and head are graduated.

� The scale on the bar is called main scale main scale main scale main scale and on the called verniervernierverniervernier

scale.scale.scale.scale.

� It is always used by placing it on the surface plate.It is always used by placing it on the surface plate.It is always used by placing it on the surface plate.It is always used by placing it on the surface plate.

� The base The base The base The base of height gauge is made up of cast iron and the beam is

made up of stainless steel.


CUTTING TOOLS

� The tools, which are used to remove the

material from the work piece, are known as

cutting tools. The cutting tools used in fitting

are hacksaws, files and chisels. These are

described below in detail.

HACKSAWHACKSAWHACKSAWHACKSAW

Depending upon the direction of cut, blades are classified as :

� Forward cutForward cutForward cutForward cut

� Backward cut. Backward cut. Backward cut. Backward cut.

Depending upon the pitch of the teeth (Distance between the two consecutive teeth) blades are classified as :

� CoarseCoarseCoarseCoarse (8-14 teeth per inch)

� MediumMediumMediumMedium (16-20 teeth per inch)

� FineFineFineFine (24-32 teeth per inch)

HACKSAWHACKSAWHACKSAWHACKSAW

� Hacksaw is used for cutting of rods, bars, pipes, flats etc. it consists of a frame, which is made from mild steel. The blade is placed inside the frame and is tightened with the help of a flange nut. The blade is made up of high carbon steel or high speed steel.

� The points of the teeth are bent in a zigzag zigzag zigzag zigzag fashion, to cut a wide groove and prevents the body of the blade from rubbing or jamming in the saw cut. The teeth of the blades are generally forward cut so in that case, pressure is applied in the forward direction only.

FILESFILESFILESFILES

� Files are multi points cutting toolsFiles are multi points cutting toolsFiles are multi points cutting toolsFiles are multi points cutting tools. It is used to

remove the material by rubbing it on the metals.

Files are available in a number of sizes, shapes and

degree of coarseness.

Classification of filesClassification of filesClassification of filesClassification of files

� On the basis of grade :

� Rough (20 teeth per inch)

� Bastard (30 teeth per inch)

� Second cut (40 teeth per inch)

� Smooth file (50 teeth per inch)

� Dead smooth (100 teeth per inch)

Rough and bastard files Rough and bastard files Rough and bastard files Rough and bastard files are the big cut files. When

the material removal is more, these file are used.

These files have bigger cut but the surface

produced is rough.

Dead smooth and smooth files Dead smooth and smooth files Dead smooth and smooth files Dead smooth and smooth files have smaller teeth

and used for finishing work. Second cut file has

degree of finish in between bastard and smooth

file.

ON THE BASIS OF SHAPE AND SIZEON THE BASIS OF SHAPE AND SIZEON THE BASIS OF SHAPE AND SIZEON THE BASIS OF SHAPE AND SIZE

� The length of the files varies from 4" to 14".

The various shapes of cross-section

available are hand file, flat file, triangular,

round, square, half round, knife-edge, pillar,

needle and mill file.

ON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTS

Single cut files.

Double cut files.

Rasp files.

ON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTSON THE BASIS OF NUMBER OF CUTS

PRECAUTIONS FOR FILES PRECAUTIONS FOR FILES PRECAUTIONS FOR FILES PRECAUTIONS FOR FILES

� Files should be stored in wooden racks.

� Files should not be used without handle or with loose fitting handle.

� The file should not be allowed to rust. To prevent it, it should be coated with machine oil. The oil should be removed before using the file.

� File cleaner should be used for cleaning the files. Use file card or hard wire brush for cleaning.

� The new file should be used first on copper, brass and then on wrought iron or mild steel.

� Never use files as a hammer.

FILING

Filing is required after chipping, cutting or to finish

the shape of the work piece.

The operation consists of the following steps

1. The work should be held tightly in the vice.

2. The file handle is hold by the right hand. Left-

hand palm is pressed against the end the file.

3. The file must remain horizontal throughout the

stroke. The stroke should be long, and steady.

1. Pressure should be applied only in the forward

direction.

2. The pressure is relieved during the return

stroke but file should remain in contact the

workpiece.

3. When quantity of material removal is more,

use rough files and for finishing cut smooth

files. Surface smoothness is generated

progressively,

CHISELSCHISELSCHISELSCHISELS

� These are used for chipping away the material

from the work piece.

� These are made up high carbon steel.

� Commonly used forms of chisels are flat, cross

cut, half round and diamond point.

� Flat chisel is used for general work. Cross cut

chisel and half round chisels are used for grooving

and diamond point chisels are used for precision

work.

PRECAUTIONS ASSOCIATED WITH CHIPPINGPRECAUTIONS ASSOCIATED WITH CHIPPINGPRECAUTIONS ASSOCIATED WITH CHIPPINGPRECAUTIONS ASSOCIATED WITH CHIPPING

The same cutting angle of the chisel must be maintained during the chipping operation.

Use proper cutting angle for proper metal.

When removing large amount of metal, it is necessary to lubricate the cutting edge frequently. This increases the life of the chisel and the chipping operation becomes easy and smooth.

Wear glasses on the eyes while doing chipping.

While doing hammering on the chisel heads, keep your fingers away.

Never use chisel as a hammer.

CHIPPINGCHIPPINGCHIPPINGCHIPPING

� The removal of thick layers of metal by chisel is known as chipping. This is carried out as follows.

� The work is properly held in a vice.

� The chisel is properly gripped in the left hand. The fingers are kept below the head of the chisel.

� The hammer is grasped in the right hand near the end of the hammer handle. Then apply the blow on the chisel.

� Lubricate the surface if needed.

CHIPPINGCHIPPINGCHIPPINGCHIPPING

STRIKING TOOLS

� Hammers are the only toots used for striking in fitting shop.

A hammer consists of a heavy iron body with a wooden

handle. The weight of the hammer ranges from 0.25 to 2

kg. The parts of a hammer are peen, eye neck, face and a

handle as shown in Fig.

THE MAIN TYPES OF HAMMERS

CARE WHILE DOING HAMMERING :CARE WHILE DOING HAMMERING :CARE WHILE DOING HAMMERING :CARE WHILE DOING HAMMERING :

(PRECAUTIONS)

1. The handle of the hammer should have proper

strength. It should be tightly fitted,

2. Use proper size hammer for proper work.

3. Wipe off any oil, if there, from handle or face

of the hammer.

4. Replace the worn out handles. Don't take risk.

5. While doing hammering, keep mind in job.

DRILLDRILLDRILLDRILL

� The tool used for making round holes is

called drill. It is a multipoint cutting tool. It is

made up of high speed steel. The parts of a

twist drill are shown as below :

REAMERREAMERREAMERREAMER

� Reamer is used to finish the drilled hole and the

operation is called reaming.

� So the reaming is a process of imparting necessary

smoothness, parallelism, roundness and accuracy in

size, to the previously drilled hole by using a reamer.

The commonly used reamer is shown below:

COUNTER SUNKCOUNTER SUNKCOUNTER SUNKCOUNTER SUNK

� Counter sunk are

taper cutters used

to make the hole

cone-shaped from

the upper end. It is

made for fitting

screws and nails.

TAPPING TAPPING TAPPING TAPPING

� The process of cutting internal threads into a

drilled hole by using a tap is known as Tapping.

� The procedure is described below :� First of all, a hole is drilled to a diameter smaller than the outside

diameter of the thread on the tap. The

� diameter of the hole to be drilled is called tapping size.

1. Tapping size = outside diameter +2 x depth of thread.

TAPSTAPSTAPSTAPS

� Taps are used for making internal threads. The

tap is provided with cutting edges hardened, so

that when it is screwed into a hole, it cuts an

internal thread to fit an external of the same

size. The taps are made of high carbon or high

speed steel These are made insets of three.

First use taper tap then use medium tap and

then use bottoming or plug tap.

TAPSTAPSTAPSTAPS

DIE AND DIE STOCKDIE AND DIE STOCKDIE AND DIE STOCKDIE AND DIE STOCK

� Die and die stock are used for cutting internal

threads. Dies are made from tool steel have

internal treads. By holding the die into die

stock, the handle is rotated by hand.

OPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINE

�DrillingDrillingDrillingDrilling - Drilling is the process of producing a hole.

This is accomplished by rotating the tool and/or work

piece. Drills (tools)are used for drilling

� ReamingReamingReamingReaming - Enlarging an existing hole with a multi-

edged tool (reamer) for dimensional accuracy and/or

surface finish. Reamers ( tools) are used for drilling

�Boring:- Enlarging an existing hole with Single point

cutting tool known as boring tool.

OPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINEOPERATIONS ON DRILLING MACHINE

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� Counter sinking Counter sinking Counter sinking Counter sinking - operation or producing a tapered

feature at the end of a hole. Most popular application

is for a flathead screw (82 degrees) to sit flat with a

surface. Counter sink tool is used for counter sinking

� Counter boring Counter boring Counter boring Counter boring - Enlarging of an existing hole at one

end. This enlarged hole is concentric with the existing

hole and is flat at the bottom. One application of this

process is to set the head of a bolt below a surface.

Counter Bore Tool is used for counter boring.78

DRILLING

DRILLING MACHINE

Fitting & measurment Tools

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