WS Lab Manual

WORKSHOP PRACTICE MANUAL (MACHINE SHOP)
SAFETY PRECAUTION
1. Always wear proper fitting apron/lab coat before starting work in machine shop. Do not
wear loose clothes.
2. Always wear safety goggles to protect your eyes against any flying chips or dust.
3. Keep your hands away from the moving cutter or work piece.
4. Cover the pulleys & belts with safety guards while working.
5. Never let your clothes & hand come in contact with the revolving chuck, pulleys, belts, etc.
6. Work piece should be held tightly between the live & dead centers.
7. Don’t touch the chips while the same are being generated by the machine because these are
extremely hot.
8. Be sure that cutting tool is tightly held in tool post.
9. Do not touch the tool tip during grinding of the tool.
10. Don’t give excessive feed to the cutting tool. It damages the tool tip & may even cause
accident.
11. You must always know the position of fire extinguisher & first aid box in the shop.
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Experiment .01
Objective:
To Draw Layout of metrology and Quality assurance Lab and investigate different types and
importance of Layout.
Theory:
1. Layout and its types

layout refers to the arrangement of physical facilities such as machinery, equipment, furniture etc. with in
the facility building in such a manner so as to have quickest flow of material at the lowest cost and with
the least wastage of time.
2. Imporance
layout is an important decision as it represents long-term commitment. An ideal layout should provide the
optimum relationship among output, floor area and manufacturing process.It facilitates the production
process, minimizes material handling, time and cost, and allows flexibility of operations, easy production
flow, makes economic use of the building, promotes effective utilization of manpower, and provides for
employee’s convenience safety, comfort at work, maximum exposure to natural light and ventilation. It is
also important because it affects the flow of material and processes, labour efficiency, supervision and
control, use of space and expansion possibilities etc.
3. Essentials
An efficient layout is one that can be instrumental in achieving the following objectives;
a) Proper and efficient utilization of available floor space
b) To esure that work proceeds from one point to another point without any delay e.g in Manufacturing
facilities.
c) Provide enough production capacity
d) Reduce material handling cost
e) Reduce hazards to personnel
f) Utilise labor efficiently
g) Increase employee morale
h) Reduce accidents
i) Provide for volume and product flexibility
j) Provide ease of supervision and control
k) Provide for employee safety and health
l) Allow ease of maintenance
m) Allow high machine or equipment utilization
n) Improve productivity
4. Types Of Layout
An discussed so for the factory layout facilitates the arrangement of machines, equipment and other
physical facilities in a planned manner within the factory premises. An entrepreneur or production
engineer must possess an expertise to lay down a proper layout for new or existing plants. It differs from
plant to plant, from location to location and from industry to industry. But the basic principles govering
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factory layout are more or less same. As far as small business is concerned, it requires a smaller area or
space and can be located in any kind of building as long as the space is available and it is convenient.
In case of manufacturing units, factory layout may be

of four types:
1) Product or line layout
2) Process or functional layout
3) Fixed position or location layout
4) Combined or line layout
4.1. Product or line Layout:
Under this, machines and equipments are arranged in one line depending upon the sequence of
operation required for the product . The materials move form one workstation to another sequentially
without any backtracking or deviation. Under this, machines are grouped in one sequence. Therefore
matereals are fed into the first machine and fineshed goods travel automatically from machine to machine,
the output of one machine becoming input of the next, e.g. in a paper mill, bamboos are fed into the
machine at one end and paper comes out at the other end. The raw material moves very fast from one
workstation to other station with a minimum work in progress storage and material handling. The
grouping of machines should be done keeping in mind the following general principles:
a) All the machine tools or other items of equipments must be placed at the point demanded by sequence
of operations.
b) There should bot be any points where one line crosses another line.
c) Materials may be fed where they are required for assembly but not necessarily at one point.
d) All the operations including assembly, testing packing must be included in the line.
4.2. Process Layout:
In this type of layout machines of similar type are arranged together at one place. E.g. Machines
performing drilling operations are arranged in the drilling department, machines performing casting
operations be grouped in the casting department. Therefore the machines are installed in the plants, which
follow the process layout. Hence, such layouts typically have drilling department, milling department
welding department, heating department and painting department etc. The process or functional layout is
followed from historical period. It evolved from the handicraft method of production. The work has to be
allocated to each department in such a way that no machines are chosen to do as many different job as
possible i.e. the emphasis is on general purpose machines. The grouping of machines according to the
process has to be done keeping in mind the following principles:
a) The distance between departments should be as short as possible for avoiding long distance movement
of materials
b) The departments should be in sequence of operations
c) The arrangement should be convenient for inspection and supervision.
4.3. Fixed Position or Location Layout:
In this type of layout, the major product being produced is fixed at one location. Equipment labour and
components are moved to that location. All facilities are brought and arranged around one work center.
This type of layout is not relevant for small scale entrepreneur or producers.
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4.4. Combined layout:
Certain manufacturing units may require all three processes namely intermittent process the continuous
process and the representative process combined process. In most of industries, only a product layout or
process layout process or fixed location layout does not exist. Thus, in manufacturing concerns where
several products are produced in repeated numbers with no likelihood of continuous production,
combined layout is followed. Generally a combination of the product and process layout or other
combinaion are found, in practice, e.g. for industries involving the fabrication of parts and assembly,
fabrication tends to employ the process layout, while the assembly areas often employ the product layout.
In soap, manufacturing, plant, the machinery manufacturing soap is arranged on the product line
principle, but ancillary services such as heating, the manufacturing of glycerin, the power house, the
water treatment plant etc. are arranged on a functional basis.
5. FACTORS INFLUENCING LAYOUT
While deciding his factory or unit or establishment or store, a small-scale businessman or Production
Engineer should keep the following factors in mind:
a) Factory building: The nature and size of the building determines the floor space available for
layout. While designing the special requirments, e.g. air conditioning, dust control, humidity
control etc. must be kept in mind.
b) Nature of product: Product layout is suitable for uniform products whereas process layout is
more appropriate for custom-made products.
c) Production process: In assembly line industries, product layout is better. In job order or
intermittent manufacturing on the other hand, process layout is desirable.
d) Type of machinery: General purpose machines are often arranged as per process layout while
special purpose machines are arranged according to product layout.
e) Repairs and maintenance: Machines should be so arranged that adequate space is avaible
between them for movement of equipment and people required for repairing the machines.
f) Human needs: Adequate arrangement should be made for cloakroom, washroom, lockers,
drinking water, toilets and other employee facilities, proper provision should be made for disposal
of effluents, if any.
g) Plant environment: Heat, light, noise, ventilation and other aspects should be duly considered,
e.g. paint shops and plating section should be located be in another hall so that dangerous fumes
can be removed through proper ventilation etc. Adequate safety arrangement should also be
made.
Thus, the layout should be conducive to health and safety of employees. It should ensure free and
efficient flow of men and materials. Future expansion and diversification may also be considered
while planing factory layout.
6. Dynamics Of Plant Layout
Plant layout is a dynamic rather than a static concept meaning thereby if once done it is not permanent in
nature rather improvement or revision in the existing plant layout must be made by keeping a track with
development of new machines or equipment, improvements in manufacturing process, changes in
materials handling devices etc. But any revision in layout must be made only when the savings resulting
from revision exceed the costs involved in such revision. Revision in plant layout may become necessary
on account of the following reasons:
1) Increase in the output of the existing product
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2) Introduction of a new product and diversification

3) Technological advancements in machinery, material, processes, product design, fuel etc.
4) Deficiencies in the layout unnoticed by the layout engineer in the beginning.
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MACHINE SHOP
The shop where machining operations are performed. Machining is a manufacturing process in
which the raw material is processes by removing unwanted material with the help of machines.
In essence, a lathe rotates a cylindrical workpiece along its axis and removes material from the
workpiece to form it into a specific shape. On a woodworking lathe, the cutting tools are usually
hand-held against a support and are moved in and out and back and forth along the surface of the
work by hand to form a shape such as a table leg. On metalworking lathes, the cutting tools are
held rigidly in a tool holder that is mounted on a movable platform called the carriage. The tool
is moved in and out by means of hand cranks and back and forth either by hand cranking or
under power from the lathe. The result is that material can be removed from the workpiece under
very precise control to produce shapes that are truly precision made. Dimensional accuracies of
one-one thousandth of an inch (.001") are typical. Because of the inherent rotational nature of a
lathe, the vast majority of the work produced on it is basically cylindrical in form. In spite of
this, the lathe is an extremely versatile machine capable of producing a surprising variety of
objects. Different machine used in machine shop are:
1. Lathe machine
2. Shaper
3. Milling machine
4. Planning machine
5. Drilling machine
6. Grinding machine
7. Threading machine
LATHE
A lathe is a powered mechanical device in which the work is held and rotated against a suitable
cutting tool for producing cylindrical forms in the metal, wood or any other machinable material.
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TYPE OF LATHE
a) Precision lathe
b) Tool room lathe
c) Capstan and turret lathe
d) Automatic lathe
e) Speed lathe
f) Engine lathe
g) Bench lathe
h) Special purpose lathe
1. Speed Lathe: Speed lathe is simplest of all types of lathes in construction and operation. The
important parts of speed lathe are following-
(1) Bed
(2) Headstock
(3) Tailstock, and
(4) Tool post mounted on an adjustable slide. It has no feed box, 1eadscrew or conventional type
of carriage. The tool is mounted on the adjustable slide and is fed into the work by hand contro1.
The speed lathe finds applications where cutting force is least such as in wood working,
spinning, centering, polishing, winding, buffing etc. This lathe has been so named because of the
very high speed of the headstock spindle.
2. Centre Lathe or Engine Lathe: The term “engine” is associated with this lathe due to the
fact that in the very early days of its development it was driven by steam engine. This lathe is the
important member of the lathe family and is the most widely used. Similar to the speed lathe, the
engine lathe has all the basic parts, e.g., bed, headstock, and tailstock. But its headstock is much
more robust in construction and contains additional mechanism for driving the lathe spindle at
multiple speeds. An engine lathe is unlike the speed lathe, the engine lathe can feed the cutting
tool both in cross and longitudinal direction with reference to the lathe axis with the help of a
carriage, feed rod and lead screw. Centre lathes or engine lathes are classified according to
methods of transmitting power to the machine. The power may be transmitted by means of belt,
electric motor or through gears.
3. Bench Lathe: This is a small lathe usually mounted on a bench. It has practically all the parts
of an engine lathe or speed lathe and it performs almost all the operations. This is used for small
and precision work.
4. Tool Room Lathe: This lathe has features similar to an engine lathe but it is much more
accurately built. It has a wide range of spindle speeds ranging from a very low to a quite high
speed up to 2500 rpm. This lathe is mainly used for precision work on tools, dies, gauges and in
machining work where accuracy is needed.
5. Capstan and Turret Lathe: The development of these 1athes results from the technological
advancement of the engine lathe and these are vastly used for mass production work. The
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distinguishing feature of this type of lathe is that the tailstock of an engine lathe is replaced by a
hexagonal turret, on the face of which multiple tools may be fitted and fed into the work in
proper sequence. Due to this arrangement, several different types of operations can be done on a
job without re-setting of work or tools, and a number of identical parts can be produced in the
minimum time.
6. Special Purpose Lathes: These lathes are constructed for special purposes and for jobs,
which cannot be accommodated or conveniently machined on a standard lathe. The wheel lathe
is made for finishing the journals and turning the tread on railroad car and locomotive wheels.
The gap bed lathe, in which a section of the bed adjacent to the headstock is removable, is used
to swing extra-large-diameter pieces. The T-lathe is used for machining of rotors for jet engines.
The bed of this lathe has T-shape. Duplicating lathe is one for duplicating the shape of a flat or
round template on to the job.
7. Automatic Lathes: These lathes are so designed that all the working and job handling
movements of the complete manufacturing process for a job are done automatically. These are
high speed, heavy duty, mass production lathes with complete automatic control.
THE PRINCIPLE PARTS OF LATHE

1. BED: The IT is the base or foundation of lathe. It is casting made in one piece. It holds or
support all other parts of lathe.
2. HEAD STOCK: It is a permanently fastened on the inner ways at the left hand end of the
bed. It supports spindle and driving arrangements. All lathe receive their power through
head stock.
3. TAILSTOCK: It is the counter part of head stock of is situated at the right end of the bed.
It is used for supporting the work when turning on centers or when a long component is
to be held in a chuck.
4. CARRIAGE: It is located between headstock. It can slide along bed guide ways and be
locked at any position by tightening the carriage lock screws. It consist of following
Five main parts;

1. APRRON: It is fastened to saddle. It contains gears and clutches for transmitting motion
from feed rod and hand wheel to the carriage. Also split nut which engages with the lead
screw during threading. The Clutch mechanism is used for transmitting motion from feed
rod whereas the split nut along with the lead screw moves the carriage during thread
cutting.
2. SADDLE: It is made up of H shaped casting. It aids carriage to slide on bed guide ways
by operating hand wheels.
3. COMPOUND REST: It supports the tool post and cutting tool in its various positions. It
may be swiveled on the cross-side to any angle in the horizontal plane.
4. CROSS-SLIDE: It is provided with a female dovetail on one side and assembled on top
of saddle having a mail dovetail.
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5. TOOL POST: It is used to hold various tool holders and tools. Three types of tool post
commonly used are;
a) Ring and rocker tool post.
b) Square head tool post.
c) Quick change tool post
Glossary of Lathe Terms
Apron: Front part of the carriage assembly on which the carriage hand wheel is mounted
Bed: Main supporting casting running the length of the lathe.
Between Centers: 1.A dimension representing the maximum length of a work piece that can be
turned between centers. For Example, A 9x20 lathe is 19" between centers; a 7x12 lathe is 12" between
centers. Lathe vendors sometimes inaccurately represent this number.
2. A method of holding a work piece by mounting it between a center in the headstock spindle and a
center in the tailstock spindle (see Center).
Carriage: Assembly that moves the tool post and cutting tool along the Ways.
Carriage Handwheel: A wheel with a handle used to move the carriage by hand by means of a rack
and pinion drive.
Center: A precision ground tapered cylinder with a 60ºpointed tip and a Morse Taper shaft. Used in the
tailstock to support the end of a long work piece. May also be used in the headstock spindle to support
work between centers at both ends.
Center Drill: A short, stubby drill used to form a pilot hole for drilling and a shallow countersunk hole
for mounting the end of a workpiece on a center.
Centerline: An imaginary line extending from the center of the spindle through the center of the
tailstock ram, representing the central axis of the lathe around which the work rotates.
Chuck: A clamping device for holding work in the lathe or for holding drills in the tailstock.
Compound: Movable platform on which the toolpost is mounted; can be set at an angle to the
workpiece. Also known as the compound slide and compound rest.
Compound Handwheel:A wheel with a handle used to move the compound slide in and out. Also
known as the compound feed.
Cross slide: Platform that moves perpendicular to the lathe axis under control of the cross-slide
handwheel.
Cross-slide Handwheel: A wheel with a handle used to move the cross-slide in and out. Also known
as the cross feed.
Faceplate: A metal plate with a flat face that is mounted on the lathe spindle to hold irregularly shaped
work.
Facing: A lathe operation in which metal is removed from the end of workpiece to create a smooth
perpendicular surface, or face
Gib: A length of steel or brass with a diamond-shaped cross-section that engages with one side of
dovetail and can be adjusted by means of screws to take up any slack in the dovetail slide. Used
to adjust the dovetail for optimum tightness and to compensate for wear.
Halfnut:
A nut formed from two halves which clamp around the leadscrew under control of the halfnut lever to
move the carriage under power driven from the leadscrew.
Halfnut Lever: Lever to engage the carriage with the leadscrew to move the
carriage under power
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Headstock: The main casting mounted on the left end of the bed, in which the spindle is mounted.
Houses the spindle speed change gears.
Lead screw: Precision screw that runs the length of the bed. Used to drive the carriage under power for
turning and thread cutting operations. Smaller lead screws are used within the cross-slide and compound
to move those parts by precise amounts.
Morse Taper:
A taper of specific dimensions used to mate matching male and female parts such that they lock together
tightly and concentrically. Tapers are of various sizes such as #0, #1, #2, #3, etc. with larger numbers
representing larger sizes. The spindle of the mini-lathe has a #3 Morse Taper and the tailstock ram has a
#2 Morse Taper.
Saddle: A casting, shaped like an "H" when viewed from above, which rides along the ways. Along
with the apron, it is one of the two main components that make up the carriage.
Spindle: Main rotating shaft on which the chuck or other work holding device is mounted. It is mounted
in precision bearings and passes through the headstock.
Spindle Through hole: A dimension indicating the minimum diameter of the hole that passes
through the spindle. A work piece with a diameter smaller than this can pass through the spindle to
facilitate working on long pieces of work. On the lathe it is 3/4" but can safely be reamed out to 13/16"
Swing: A dimension representing the largest diameter workpiece that a lathe can rotate. The 9x20 lathe
has a 9" swing, meaning that the maximum size workpiece that can rotate without hitting the
bed is 9" in diameter.
Tailstock: Cast iron assembly that can slide along the ways and be locked in place. Used to hold long
work in place or to mount a drill chuck for drilling into the end of the work.
Tailstock Hand wheel: A wheel with a handle used to move the tailstock ram in and out of the
tailstock casting.
Tailstock Ram: A piston-type shaft that can be moved in and out of the tailstock by turning the
tailstock handwheel. Has a tapered internal bore to accept a #2 Morse Taper shank.
Tool: A cutting tool used to remove metal from a workpiece; usually made of High Speed Steel or
carbide.
Tool Blank: A piece of High Speed Steel from which a cutting tool is ground on a bench grinder.
Typically 5/16" square by 2 1/2" long for mini-lathe use.
Tool post: A holding device mounted on the compound into which the cutting tool is clamped
Turning: A lathe operation in which metal is removed from the outside diameter of the workpiece, thus
reducing its diameter to a desired size.
Ways: Precision ground surfaces along the top of the bed on which the saddle rides. The ways are
precisely aligned with the centerline of the lathe.
LEGS: There are supports which carry entire load of the machine. Legs are casted and it is
placed on the floor of the shop on foundation by grouting. The left leg acts as a housing for the
motor, the pulleys and the counter shaft at the same time the right leg acts as a housing or the
coolant tank, pump and the connecting parts.
SPECIFICATION OF LATHE: The size of the lathe is specified by one of the following
ways:
A) Length of the bed.

B) Distance between centers
C) Diameter of the work which can be turned between the ways
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D) Swing over carriage
Measurements involved in operation performed on Lathe:
Following measuring tools are commonly used while working on the lathe machine.
 Vernier calipers
 Micrometer screw gauge
 Meter tape
 Steel ruler
Vernier calipers
Measuring instruments are used to measure various physical quantities such as length, mass, time,
diameter of different things. Measuring instruments used in the past were not reliable and accurate as we
use today. Hence we use the Vernier caliper for measuring the diameter, length depth or height of
cylinder. The accuracy obtained in measurements using a meter rule is up to 1mm. However accuracy
greater than 1 mm can be obtained by using Vernier calipers.
A Vernier caliper consists of two jaws. One is fixed jaw with main scale attached to it.
Main scale has centimeter and millimeter marks on it. The other jaw is a moveable. It has Vernier scale
having 10 divisions over it such that each of its division is 0.9mm. The difference between one small
division on main scale division and one Vernier scale division is 0.1mm. It is called least count (LC) of
the Vernier calipers. It is defined as the minimum distance measure by the Vernier caliper. Least count of
the Vernier calipers can also be found as given below:
Smallest reading on main scale

Least Count of Vernier caliper =
No.of divisions on Vernier scale
1
= mm
10
11
= 0.1 mm
Zero Errors of Vernier Caliper
When the jaws are closed, the Vernier zero mark coincides with the zero mark on its fixed main scale.
Before taking any reading it is good practice to close the jaws or faces of the instrument to make sure that
the reading is zero. If it is not, then note the reading. This reading is called “zero error”.
The zero error is of two types:
a. Positive zero error; and

b. Negative zero error.
Positive Zero Error
If the zero on the Vernier scale is to the right of the main scale, then the error is said to be positive zero
error and so the zero correction should be subtracted from the reading which is measured.
Positive Zero Error value= coinciding division X least count
= 5 x 0.1
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=0.5
Negative Zero Error
If the zero on the Vernier scale is to the left of the main scale, then the error is said to be negative zero
error and so the zero correction should be added from the reading which is measured. Before adding the
negative error first we take the difference
Difference= total no. of divisions – Coinciding division
=10-4
=6
Here Negative zero error value = 6 x 0.1 = 0.6
Procedure:
 Place the solid cylinder between jaws of the Vernier calipers
 Close the jaws till they press the opposite sides of the object gently.
 Note the complete division of main scale
 Next find the Vernier scale division that is coinciding with any division on the main scale.
Multiply it by least count of Vernier calipers and add it in the main scale reading.
 This is equal to the diameter of the solid cylinder.
 Add zero error to get correct measurement.
 Repeat the above procedure and record at least observations with solid cylinder displaced or
rotated each time.
Micrometer screw gauge:
A screw gauge is an instrument that is used to measure small length with accuracy greater than a
Vernier Caliper. It is also called as micrometer screw gauge. A simple screw gauge consists of a
u-shaped metal frame with a metal stud (Anvil face) at its one end.
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A hollow cylinder or sleeve has a millimeter scale over it along a line called index line parallel
to its axis. The hollow cylinder acts as a nut. It is fixed at the end of U-shaped frame opposite to
the stud. A thimble has a threaded spindle inside it. As the thimble completes one revolution, the
thimble spindle moves 1mm along the index line. It is because the distance between consecutive
threads on the spindle is 1mm. this distance is called the pitch of screw on the spindle.
The thimble has 100 divisions around its one end. It is the circular scale of the screw gauge. As
thimble completes one rotation, 100 divisions pass the index line and the thimble moves 1mm
along the main scale. Thus each division of circular scale crossing the index line moves the
thimble through 1⁄100mm or 0.01mm on the main scale. Least count of a screw gauge can also
be found as given below:
𝐏𝐢𝐭𝐜𝐡 𝐨𝐟 𝐬𝐜𝐫𝐞𝐰 𝐠𝐚𝐮𝐠𝐞

Least count=
𝐍𝐨.𝐨𝐟 𝐝𝐢𝐯𝐢𝐬𝐢𝐨𝐧𝐬 𝐨𝐧 𝐜𝐢𝐫𝐜𝐮𝐥𝐚𝐫 𝐬𝐜𝐚𝐥𝐞
𝟏 𝐦𝐦
=
𝟏𝟎𝟎
The least count of the screw gauge is 0.01mm or .001 cm.
Zero Error for micrometer screw gauge
Positive Zero Error
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If the zero marking on the thimble is below the datum line, the micrometer has a positive zero error.
Whatever reading we take on this micrometer we would have to subtract the zero correction from the
readings.
Negative Zero Error
If the zero marking on the thimble is above the datum line, the micrometer has a negative zero
error. Whatever readings we take on this micrometer we would have to add the zero correction from the
readings.
Note: You do not have to memories positive error = subtract, negative error = add, just think this through
for a while. It is rather straightforward and intuitive.
Procedure:
1. Close the gap between the spindle and the stud of the screw gauge by turning the ratchet
in the clockwise direction.
2. Note main scale as circular scale reading to find zero error and hence zero correction of
the screw gauge.
To find zero error, close the gap between the spindle and the stud of the screw gauge by
rotating the ratchet in the clockwise direction. If zero of circular scale coincides with the
index line, then the zero error will be zero.
Zero error will be positive if zero of circular scale is behind the index line. In this case,
multiply the number of division of the circular scale that has not crossed the index line with
the least count of screw gauge to find zero error.
Zero error will be negative if zero of circular scale has crossed the index line. In this case,
multiply the number of divisions of the circular scale that has crossed the index line with the
least count of screw gauge to find negative zero error.
3. Open the gap between stud and spindle

of the screw gauge by turning the ratchet
in anticlockwise direction place the
given wire in the gap. Turn the ratchet
so that the object is pressed gently
between the stud and spindle.
4. Note main scale as well as circular scale
readings to find the diameter of the
given wire.
5. Apply zero correction to get the correct
diameter of the wire.
Repeat these steps 3, 4 and 5 at different places of the wire to obtain its average diameter.
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 Meter tape and Steel ruler are easy to use and understand.
CUTTING SPEED, FEED AND DEPTH OF CUT:
Cutting speed is defined as the speed at which the work moves with respect to the tool (usually
measured in feet per minute). Feed rate is defined as the distance the tool travels during one
revolution of the part. Cutting speed and feed determines the surface finish, power requirements,
and material removal rate. The primary factor in choosing feed and speed is the material to be
cut. However, one should also consider material of the tool, rigidity of the workpiece, size and
condition of the lathe, and depth of cut. For most Aluminum alloys, on a roughing cut (.010 to
.020 inches depth of cut) run at 600 fpm. On a finishing cut (.002 to .010 depth of cut) run at
1000 fpm. To calculate the proper spindle speed, divide the desired cutting speed by the
circumference of the work. Experiment with feed rates to achieve the desired finish. In
considering depth of cut, it's important to remember that for each thousandth depth of cut, the
work diameter is reduced by two thousandths.
Lathe Speeds and Feeds.

General.
Determining the most advantageous feeds and speeds for a particular lathe operation depends on
numerous factors such as the kind of material being worked on, the type of tool, the diameter and length
of the workpiece, the type of cut desired (rough or finished), the cutting oil used, and the condition of the
lathe being used.
Cutting Speed.
(a) The cutting speed of a cutting tool is defined as the number of feet of workpiece surface, measured at
the circumference, that pass the cutting tool in 1 minute. The cutting speed, expressed in feet per minute
(fpm), must not be confused with the spindle speed (N) of the lathe which is expressed in revolutions per
minute (rpm). To obtain uniform cutting speed, the lathe spindle must be revolved faster for workpieces
of small diameter and slower for workpieces of large diameters.
(b)Another factor to consider when

selecting cutting speed includes the
use of cutting oils, the length and
diameter of the workpiece, and the
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condition of the lathe. If a large stream of proper cutting oil is applied to the workpiece at the cutting tool,
the cutting speed can be increased as much as 40 percent. If the diameter of the workpiece is small and its
length is great enough to set up vibrations due to the speed, a poor finish
will result; to correct this condition, the speed must necessarily be reduced. The lathe may also be in poor
condition so that high speeds will cause harmful vibrations.
Feed.
(a) General. Feed is the term applied to the distance the cutting tool advances for each revolution of the
workpiece. Feed is specified in inches per revolution. Since the best feed depends upon a number of
factors such as depth of cut, type of material, size of workpiece, and condition of the
lathe, it is difficult to list the best feed for the different materials.
(b) Rough Cuts.
For rough cuts, the feed may be relatively heavy since the surface need not be exceptionally smooth. For
most materials, the feed for rough cuts should be 0.010 to 0.020 inch per revolution. The feed may be
0.040 inch on large lathes with larger diameter workpieces. Care must be taken when turning slender
workpieces as a heavy cut may bend the piece, ruining it. In this case, it is best to reduce the feed to 0.008
- 0.015 inch per revolution.
(c) Finish Cuts.
For finish cuts, a light feed is necessary since a heavy feed causes a built-up edge to form on the surface,
which produces a poor finish. If a large amount of stock is to be removed, it is advisable to take one or
more roughing cuts and then take light finishing cuts at relatively high speeds. For most materials, the
feed for finishing cuts should be 0.003 to 0.010 inch per revolution. An exception is finishing soft metal
like aluminum where a broad nose cutting tool is used at feeds as great as 1/8 to 1/2 inch per revolution.
Depth of Cut.
(a) General.
The depth of cut regulates the reduction in the diameter of the workpiece for each longitudinal traverse of
the cutting tool. The workpiece diameter is reduced by twice the depth of the cut in each complete
traverse of the cutting tool. Generally, the deeper the cut, the slower the speed, since a deep cut requires
more power.
(b) Rough Cuts.
The depth of the cut for roughing is generally five to ten times deeper than the feed. The reason for this is
that more of the cutting edge of the cutting tool is in contact with the workpiece for the amount of metal
being removed permitting a greater speed to he used. For roughing with feeds of from 0.010 to 0.020 inch
per revolution, the depth of cut should be between 3/16 and 1/4 inch. Deeper cuts up to 1/2 inch can be
taken but the feed should be proportionately reduced. A heavy cut may cause the workpiece and the
cutting tool to chatter; in this case the depth of cut should be reduced.
(c) Finish Cuts.
17
Finish cuts are generally very light; therefore, the cutting speed can be increased since the chip is thin.
d. Cutting Oils.
(1) General.
The chief purpose of cutting oil is to cool the cutting tool and the workpiece. The name "coolant" is often
given to the oil. A cutting tool will last longer and will be capable of withstanding greater speeds without
overheating when a cutting oil is used. A cutting oil also helps lubricate the cutting tools, improves the
finish of the workpiece, guards against rusting, and washes away chips from the cutting area.
(2) Use.
In production operations, the practice is to flood the workpiece and the cutting tool with cutting oil in
order to obtain the full benefit of its use. For effective cooling, it is important that the oil be directed at the
exact point of the cutting tool contact. A large stream at low velocity is preferred to a small stream at high
velocity. In small shops where pump equipment is not available, cutting oils are used only for finishing
and delicate operations. It is general practice in this case to apply the cutting oil only when actually
required.
LATHE OPERATIONS:
For performing the various machining operations in a lathe, the job is being supported and driven
by anyone of the following methods.
1. Job is held and driven by chuck with the other end supported on the tail stock centre.
2. Job is held between centers and driven by carriers and catch plates.
3. Job is held on a mandrel, which is supported between centers and driven by carriers and catch
plates.
4. Job is held and driven by a chuck or a faceplate or an angle plate.
The above methods for holding the job can be classified under two headings namely job held
between centers and job held by a chuck or any other fixture. The various important lathe
operations are depicted through Fig. (a), (b) and (c). The operations performed in a lathe can be
understood by three major categories
(a) Operations, which can be performed in a lathe either by holding the workpiece
between centers or by a chuck are:
1. Straight turning
2. Shoulder turning
3. Taper turning
4. Chamfering
5. Eccentric turning
6. Thread cutting
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7. Facing
8. Forming
9. Filing
10. Polishing
11. Grooving
12. Knurling
13. Spinning
14. Spring winding
(b) Operations which are performed by holding the work by a chuck or a faceplate or an
angle plate are:
1. Undercutting
2. Parting-off
3. Internal thread cutting
4. Drilling
5. Reaming
6. Boring
7. Counter boring
8. Taper boring
9. Tapping
19
(c) Operations which are performed by using special lathe attachments are:
1. Milling
2. Grinding
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SHAPER
Shaper is a versatile machine which is primarily intended for producing flat surfaces. The
surfaces may be horizontal, vertical or inclined. This machine involves the used of single
point tool held in a properly designed tool box mounted on a reciprocating ram.
CLASSIFICATION OF SHAPERS;
1. According to the ram driving mechanism
a) Crank shaper
b) Geared shaper
c) Hydraulic shaper
2. According to position and travel of ram
a) Horizontal shaper
b) vertical shaper
3. According to direction of cutting stroke
a) Push cut shaper
b) draw cut shaper
4. According to design of table
a) Plain shaper
b) Universal shaper
MILLING
It is a machine tool in which metal is removed by means of a Revolving cutter with many teeth,
Each teeth has an edge which removes metal.
TYPE OF MILLING MACHINE

(1) COLUMN & KNEE TYPE MILLING;
(a) Horizontal milling machine (b) vertical milling machine
(c) Universal milling machine.
(2) PLANER MILLING MACHINE
(3) FIXED BED TYPE
(4) SPECIAL purpose milling machine.
PARTS OF MILLING
(1) BASE; It is a heavy casting on which column and other parts are mounted.
(2) COLUMN; There are guide ways on the front face of the column on which knee slides.
(3) KNEE; It supports the saddle table, work piece and other damping device.
(4) SADDLE; It is mounted on the knee and can be moved by a hand wheel.
(5) TABLE; It is mounted on the saddle and can be moved by hand or automatic power feed.
21
(6) ARBOR; It holds and drives different types of milling cutters.

(7) SPINDLE; It gets power from gears, belt drivers to drive the moter. It has the power to
add or remove milling cutter on the arbor.
OTHER TOOLS IN MACHINE SHOP

Measuring Tools
1. Steel Rule
2. Vernier Caliper (L.C.-0.02mm)
3. Out Side Micro Meter (0.01mm)
4. In side caliper / out side caliper
5. Threading gauge
6. Vernier height gauge
7. Dial indicator
8. Surface gauge
9. Radius gauge
10. Feeler gauge
11. Surface plate
CUTTING TOOLS
1. Single point cutting tool
2. Internal / external threading tool
3. Parting off tool
4. Boring tool
5. Knurling tool
6. Round split die / spring die
7. Tap set
8. Twist drill
9. Taper shank drill
10. Smooth file
MISCELLANEOUS TOOLS
1. Double ended spanner
2. Ring spanner
3. Allen key set
4. (l) shape socket wrench
LATHE MACHINE ACCESSORIES & ATTACHMENT

1. Live Centre / dead center or revolving center.
2. Job or dog carrier
3. Mandrel
22
4. Collet chuck
5. Drill chuck
6. Steady rest
7. Face plate
8. Angle plate
9. Three jaw chuck or four jaw chuck
23
Experiment No.01
Objective: To prepare the job as per the specifications provided
Machine Tools used: Lathe Machine (Specification H.P. =0.75 H.P. Swing Diameter =455,
Distance between centers 1000mm.
List of tools: Engineering Steel Rule 6”, Outside caliper, Vernier calipers, Flat smooth file,
Single point cutting tool, Knurling tool, Center drill, Drill chuck ½”, Spanner set, Parting off or
necking tool, Thread gauge, Threading tool, Parting tool, Lathe Dog carrier etc.
Materials Used: Mild steel bar (25 mm dia.)
List of Operations: Cutting, Facing, center drilling, Plain turning, Taper turning, Necking,
Knurling, Threading, chamfering, Filing Oiling.
Drawing: See diagram
Procedure:
1. Understand the job drawing thoroughly and plan the job.
2. Cut off a 130mm long piece from 40 mm dia. Bar.
3. Hold the work piece in the Lathe chuck and perform facing and center drill operations.
Repeat the same on the other side also.
4. Hold the job in between live and dead centers.
5. Perform plain turning (L=35mm, diameter, chamfering and knurling operations on one
side and interchange the faces axially.
6. perform plane turning by swiveling the compound rest at an angle 4
7. Now start threading by setting levers as per requirement.
8. After filing if required, take off the job from m/c and do oiling in the whole job for the
protection from the rust.
Precautions:
1. Don’t wear loose clothes while working on the machine.
2. Work piece should be held tightly between the live and dead centers.
3. Always clean machine before use.
4. Cutting tools should be held tightly in the tool holder.
5. Never let your clothes and hand come in contact with the revolving chuck, pulleys etc.
6. Do not touch the chips when machine is removing them
7. Do not give large feed to the cutting tool.
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Figure: Diagram of the Workpiece to be prepared
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Shaper Machine
Introduction
Shaper is a reciprocating type of machine tool in which the ram moves the cutting tool back and
forth in a straight line. It is needed primarily for the production of flat surfaces. It can also make
slots, grooves and keyways in the shafts. These surfaces can be horizontal, vertical, or inclined.
In general, the shaper can produce any surface consisting of straight-line elements. Modern
shapers can also produce contoured surface. A shaper is used to produce flat (plane) surfaces by
single point cutting tool similar to a lathe tool.
Working Principle of Shaper

A single point cutting tool is held in the tool holder that is mounted on the ram. The workpiece is
stiffly held in a vice or clamped directly on the table. The table can be supported at the outer end.
The ram reciprocates and cutting tool mounted in tool holder moves forward and backward over
the specimen. In a standard shaper, cutting of workpiece takes place during the forward stroke of
the ram. The backward stroke remains idle and no cutting takes place throughout this stroke. The
feed is given to the workpiece and depth of cut is controlled by moving the tool downward
towards the workpiece. The time taken throughout the idle stroke is less as compared to forward
cutting stroke and this is obtained by quick return mechanism.
Types of Shapers
Shapers are classified under the following headings:
(1) According to the type of mechanism used for giving reciprocating motion to the ram
 Crank type
 Geared type
 Hydraulic type
(2) According to the type of design of the table:
 Standard shaper
 Universal shaper
(3) According to the position and travel of ram:
 Horizontal type
 Vertical type
 Traveling head type
(4) According to the type of cutting stroke:
 Push type
 Draw type.
Crank Shaper
This is the most common form of shaper. It uses a crank mechanism to change circular motion of
an outsized gear called “bull gear” fixed within the machine to reciprocating motion of the ram.
The bull gear receives power either from an individual motor or from an overhead line shaft if it
is a belt-driven shaper.
Geared Shaper
Geared shaper makes use of rack and pinion association to achieve reciprocating motion of the
ram. Presently this type of shaper is not commonly used.
Hydraulic Shaper
In hydraulic shaper, reciprocating motion of the ram is achieved by hydraulic power. For
generation of hydraulic power, oil under high pressure is pumped into the operating cylinder
fitted with piston. The piston end is connected to the ram via piston rod. The high pressure oil
causes the piston to reciprocate and this reciprocating motion is transferred to the ram of shaper.
The vital benefit of this type of shaper is that the cutting speed and force of the ram drive are
constant from beginning to the end of the cut.
Standard Shaper
In standard shaper, the table has only two movements, horizontal and vertical, to offer the feed.
Universal Shaper
A universal shaper is commonly employed in tool room work. In this type of shaper, in addition
to the horizontal and vertical movements, the table can be move about an axis parallel to the ram
ways, and the upper portion of the table can be tilted about a second horizontal axis
perpendicular to the first axis.
Horizontal Shaper
In this type of shaper, the ram holding the tool reciprocates in a horizontal axis.
Vertical Shaper
In vertical shaper, the ram reciprocates in a vertical axis. These shapers are mainly used for
machining keyways, slots or grooves, and internal surfaces.
Travelling Head Shaper
In this type of shaper, the ram reciprocates and also moves crosswise to give the specified feed.
Push Type Shaper
This is the foremost general form of shaper used in common practice, in which the metal is
removed when the ram moves away from the column, i.e. pushes the work.
Draw Type Shaper
In this type of shaper, the cutting of metal takes place when the ram moves towards the column
of the machine, i.e. moves the work towards the machine. The tool is set in a reversed direction
to that of a standard shaper.
Principal Parts of Shaper
The main parts are given as under.
1. Base
2. Column
3. Cross-rail
4. Saddle
5. Table
6. Ram
7. Tool head
8. Clapper box
9. Apron clamping bolt
10. Down feed hand wheel
11. Swivel base degree graduations
12. Position of stroke adjustment hand wheel
13. Ram block locking handle
14. Driving pulley
15. Feed disc
16. Whitworth’s Quick Return Mechanism
17. Elevating screw
Base
It is rigid and heavy cast iron body to resist vibration and takes up high compressive load. It
holds all other parts of the machine, which are fixed over it. The base may be rigidly bolted to
the floor of the shop or on the bench according to the size of the machine.
Column
The column is a box shaped casting mounted upon the base. It houses the ram-driving
mechanism. Two accurately machined guide ways are provided on the top of the column on
which the ram reciprocates.
Cross rail
Cross rail of shaper has two parallel guide ways on its top in the vertical plane that is
perpendicular to the rail axis. It is fixed on the front vertical guide ways of the column.
It consists of mechanism for raising and lowering the table to facilitate different sizes of
specimen by rotating an elevating screw which causes the cross rail to slide up and down on the
vertical face of the column. A horizontal cross feed screw is fitted within the cross rail and
parallel to the top guide ways of the cross rail. This screw actuates the table to move in a
crosswise direction.
Saddle
The saddle is located on the cross rail and holds the table on its top. Crosswise movement of the
saddle by rotation the cross feed screw by hand or power causes the table to move sideways.
Table
The table is a box like casting having T -slots both on the top and sides for clamping the work. It
is bolted to the saddle and receives crosswise and vertical movements from the saddle and cross
rail.
Ram
It is the reciprocating part of the shaper, which reciprocates on the guide ways provided above
the column. Ram is connected to the reciprocating mechanism contained within the column.
Tool head
The tool head of a shaper performs the subsequent functions
(1) It holds the tool rigidly,
(2) It gives vertical and angular feed motion of the tool, and
(3) It permits the tool to have an automatic relief during its return stroke.
The different parts of tool head of shaper are apron clamping bolt, clapper box, tool post, down
feed, screw micrometer dial, down feed screw, vertical slide, apron washer, apron swivel pin,
and swivel base. By rotating the down feed screw handle, the vertical slide carrying the tool
gives down feed or angular feed movement while machining vertical or angular surface. The
amount of feed or depth of cut can be controlled by a micrometer dial on the top of the down
feed screw.
Apron consisting of clapper box, clapper block and tool post is fitted upon the vertical slide by a
screw. The two vertical walls on the apron called clapper box houses the clapper block, which is
connected via hinge pin. The tool post is mounted upon the clapper block. On the forward cutting
stroke the clapper block fits tightly to the clapper box to make a rigid tool support. On the return
stroke a slight frictional drag of the tool on the work lifts the block out of the clapper box a
sufficient amount preventing the tool cutting edge from dragging and consequent wear. The work
surface is also prevented from any damage due to dragging.
Specification of a Shaper
The dimension of a shaper is specified by the maximum length of stroke or cut it can make.
Commonly the size of shaper ranges from 175 to 900 mm. Besides the length of stroke, other
particulars, such as the type of drive (belt drive or individual motor drive), floor area required,
weight of the machine, cutting to return stroke ratio, number and amount of feed, power input
etc. are also sometimes needed for complete specification of a shaper.
Cutting Speed of the Shaper:
{NL(1+m)}/1000 m/min
N= number of double strokes or cycles of the ram/min (one double stroke means one cutting and
one idle or return stroke)
L= Length of ram stroke in mm
m= cutting stroke time
Feed: f
It is expressed as millimeters per double stroke or simply millimeters per stroke because no
cutting is done in reverse stroke. Feed is given using feed mechanism in the horizontal direction.
Depth of cut: d
Depth of cut d is the thickness of material removed in one cut, in millimeter. Depth is given in
the Vertical direction. Depth of cut may be given by lowering the tool using tool head slide or by
lifting the table.
Shaper Mechanism
In a shaper, rotary motion of the drive is converted into reciprocating motion of the ram by the
mechanism fixed within the column or the machine. In a standard shaper metal is removed in the
forward cutting stroke, while the return stroke goes idle and no metal is removed during this
stroke. The shaper mechanism is made so that it moves the ram holding the tool at a
comparatively slower speed during forward stroke, whereas during the return stroke it allows the
ram to move at a faster speed to reduce the idle return time. This mechanism is known as quick
return mechanism. The reciprocating movement of the ram and the quick return mechanism of
the machine are generally achieved by subsequent methods:
(1) Crank and slotted link mechanism
(2) Whitworth quick return mechanism
(3) Hydraulic shaper mechanism
Crank and Slotted Link Mechanism
In crank and slotted link mechanism the pinion receives its motion from an individual motor or
overhead line shaft and transmits the motion or power to the bull gear.
Bull gear is a massive gear fitted within the column. Speed of the bull gear may be controlled via
different combination of gearing or by simply shifting the belt on the step cone pulley. A radial
slide is fitted to the centre of the bull gear. This radial slide includes a sliding block into which
the crank pin is fitted. Rotation of the bull gear will cause the bush pin to revolve at a uniform
speed. Sliding block, which is fitted upon the crank pin is fitted within the slotted link. This
slotted link is also called the rocker arm. It is pivoted at its bottom end attached to the frame of
the column. The upper end of the rocker arm is forked and connected to the ram block via a pin.
With the rotation of bull gear, crank pin will revolve on the crank pin circle, and simultaneously
move up and down the slot in the slotted link giving it a rocking movement, which is
communicated to the ram. Hence the rotary motion of the bull gear is converted to reciprocating
motion of the ram.
Surfaces Produced On Shaper
1. Horizontal plain surface
2. Vertical plain surface
3. Inclined surface
4. Grooved surface
5. Slotted surface
6. Stepped surface
Shaper Operations
A shaper is a machine tool primarily designed to generate a flat surface by a single point cutting
tool. Besides this, it may also be used to perform many other operations. The distinctive
operations, which a shaper can perform, are as follows
Planer
The planer is almost exactly similar to a shaper, and is primarily intended to produce
plane and flat surfaces by a single point cutting tool. The fundamental difference
between a shaper and planer is that the table reciprocates past the stationary cutting
tool and feed is supplied by the lateral movement of the tool, where as in a shaper the
tool reciprocates and the feed is given by the crosswise movement of the table.
Longer stroke of practically unlimited length can be obtained by having the work
piece attached to a long, horizontal, reciprocating bed while the tool is attached to a
massive column or arch or, rather, a cross-rail with a lead screw that generates the
feed movement.
Most planer cut in one; some, in both directions. The slots and holes are provided for
bolts, keys, pins for holding and locating work pieces on the finished table top.
The large work that is not expected to be machines on other machines, such as shapers
is conveniently machined on planners.
Slotter
The slotter machine operates almost on the same principle as that of a shaper. The
major difference between a slotter and shaper is that in a slotter the ram holding the
tool reciprocates in a vertical axis, whereas in a shaper the ram holding the tool
reciprocates in a horizontal axis. A slotter is therefore, considered a vertical shaper
and they are almost similar to each other as regards their construction, operation, and
use.
The slotter is used for cutting grooves, key ways, and slots of various shapes, for
making both internal and external regular and irregular surfaces.
NC-CNC Machine Tools
Numerical control or computerized numerical control is a technique of automatically

operating a productive facility based on code of letters, numbers and special
characters. The complete set of coded instructions; responsible for executing an
operation is called part programme. In computer-aided part programming, much of the
tedious computational work needed in manual programming is performed by the
computer microprocessor. This programme is translated into electrical signals to drive
various motors to operate the machine to carry out the required operations. Avoidance
of human intervention, omission of conventional tooling and fixturing and quick
change capability of NC system are the primary factors considered to decide the level
of acceptance of machine tools for a particular job. All NC/CNC machine tools are
provided with drive motors and other accessories to do auxiliary functions of the
machine along with the work table, spindle and other hardware of the traditional
machine tools.
WORKSHOP PRACTICE MANUAL (FITTINGS SHOP)
Fitting Shop
SAFETY PRECAUTIONS
1. Never operate any machine unless you know how to operate it.
2. Always wear uniform in the workshop, never wear loose clothes.
3. Never touch moving parts, belts or rotating tools etc.
4. In case of any fire, the electric supply should be disconnected.
5. Always move the hacksaw in perfect straight and horizontal direction.
6. Never tilt the hacksaw blade while sawing.
7. The blade should be tightened sufficiently.
8. Grip the job in bench-wise properly,
9. Hacksaw blade should be fixed in proper direction and tightened
10. Use water as a coolant while sawing.
11. Hold the chisel firmly while chipping.
12. Drill the holes centralizing on pop marks, give gradual feed.
13. Check the dimensions time to time carefully with Vernier clipper.
14. Tap should be held perpendicular and rotated every half turn forward reverse quarter
turn backward.
15. Use lubricating oil during tapping.
16. Always keep your mind on the job.
1
FITTING SHOP
INTRODUCTION
Fitting jobs involve the removal of excess / unwanted material from a blanks with the help of
hand tools so that they could be assembled as specified in drawing. It is done for the assembly
practice by mating surfaces/edges of components leading to assembly.
PHYSICAL PROPERTIES OF METALS
1. Lustre: Lustre is the ability of a metal surface to reflect light rays.
2. Colour: Colour is the property of a metal to show specific surface appearance.
3. Plasticity: This is the property of metal where it can be converted in to required shape
and size by application of heat or pressure both.
4. Elasticity: It is the property of metal by which it return back to its original shape and size
after removal of external force / pressure.
5. Malleability: By this property metal can be drawn in the form of a thinner sheet without
failure.
6. Toughness: Due to this property metal can withstand bending without failure.
7. Ductility: By this property metal can be drawn in the form of wires without failure.
CLASSIFICATION OF METALS
Metals are classified into two categories:
1. Ferrous Metals – In ferrous metals iron acts as base (highest per centage) metal.. Some
other materials like carbon, sulfur, nickel, etc are also mixed into ferrous metals to
change the properties. They are magnetic in nature. Some ferrous metals are discussed as
under.
2
i) Steel – Steel is a mixture of iron, carbon and other allo ying elements.
(a) Plain Carbon Steel: is a mixture of iron, carbon with negligible alloying
elements. Low Carbon Steel – Carbon content 0.05 to 0.30%.
Medium Carbon Steel - Carbon content 0.30 to

0.60%. High Carbon Steel - Carbon content 0.60 to
1.50%.
(b) Alloy Steel – Alloy steel is made by combining some percentage of additional
elements like nickel, phosphorous, silicon, chromium, molybdenum in the
plain carbon steel to give strength, hardness, resistance to corrosion
properties.
i. Tool Steel – is alloy steel used for making cutting tools, mainly
designated as HSS (High Speed Steel) with 18% tungsten, 4%
chromium, 1% vanadium and 0.7% carbon.
ii. Invar steel – is an alloy steel with 36% Nickel lea ding to zero
coefficient of thermal expansion used for making precision
instruments.
iii. Spring Steel – alloy steel used for making springs.
ii) Cast Iron – also referred, as iron is a ferrous metal contai ning more than 2% of
carbon is known as cast iron. It is hard and brittle material, used in machine beds,
heavy parts of machines.
iii) Wrought Iron – It is almost pure iron containing 99.9% of iron. It is ductile and
soft.
2. Non Ferrous Metals - The metals which has base metal other than iron are known as non
ferrous metals, copper, aluminum, brass, bronze, tin, lead are common non ferrous
metals.
i). Copper: Reddish brown color, soft, ductile, high electrical and thermal conductivity.
ii). Brass: Alloy of copper and zinc, soft and ductile.

iii). Bronze: Alloy of tin and copper, wear resistance material.
3
iv). Aluminum: Soft metal, white in color, light in weight, good electrical
conductivity.
v). Gun metal: Alloy of copper, tin and zinc, used in making casting.
TOOLS USED IN FITTING SHOP

CLAMPING TOOLS
Clamping tools are used for holding the job firmly during various fitting operations.
i). Bench vice: It is a common tool for holding the jobs. It consists of cast iron body and
iron jaws .The jaws are opened up to required length, job is placed in the jaws and is
fully tightened with handle.
ii). Leg vice: It is stronger than bench vice and used for heavy work.
iii). Hand vice: It is used to grip very small objects.
iv). Pin vice: Pin vice is used to hold wire or small diameter rods.
v). Pipe vice: It is used to hold pipes. It grips the pipe at four places and is fixed on
bench or can be grouted.
MEASURING AND MARKING TOOLS
i). Try Square: It is used for checking square ness of two surfaces. It consists of a blade
Made up of steel, which is attached to base at 90°.
ii). Bevel Protector: It consists of a steel dial divided into 360° divisions, used for
Measuring angles.
iii). Combination Set – Multipurpose instrument can be used as a protector, a level, a meter,
a center square and a Try square.
iv). Centre Square – It is used to find the center of the round jobs, Angle of punching end is
60°.
v). Scriber and Surface Gauge – It is used for marking of lines parallel to a surface. Scriber
Mounted on a vertical bar is called surface gauge.
4
vi). Dot Punch – It is used for marking dotted lines. Angle of punching end is 60°.
vii). Centre Punch – It is like a dot punch used to mark the center of hole before drilling.
Angle of punch end is 90°
viii). Surface Plate – Surface plate is used for testing the flatness, trueness of surfaces; its
upper face is planed to form a very smooth surface.
ix). Angle Plate – It consists of cast iron in which two ribs of metal are standing at right
angle to each other, used for holding and supporting the jobs.
x). ‘V’ Block – It is used for supporting as well as marking of round jobs.
xi). Steel Rules – It is made up of stainless steel and marked in inches or millimeters,
available in various sizes ½ ft to 3 ft.
xii). Vernier Caliper – It is a precision instrument used for measuring lengths and diameters.
Minimum dimension that can be expressed on Vernier caliper is known as least count,
which is usually 0.001 or 0.02 mm.
xiii). Micrometer – It is used for measuring diameters or thickness of any Job. The graduation
on micrometers is available in inches as well as in millimeters.
xiv). Dial Indicator – A round gauge in which a pointer moves over a graduated scale. The
movement is magnified through links. It is used to check the run out or ovality of Jobs.
xv). Dividers – Dividers have two legs having sharp feet. It is used for marking arcs, dividing
a line or transferring the dimensions.
xvi). Calipers: it is generally used to measure the inside or outside diameters. There are
four types of calipers.
a) Outside calipers
b) Inside calipers
c) Spring calipers
d) Odd leg calipers
5
xvii) Gauges
i).Depth Gauge: It is used to measure the depth of a hole. The beam is graduated in
inches or millimeters.
ii).Feelers Gauge: It is used to check the gap between two mating parts. It consists
of a number of metal leaves of different thickness marked on the leaves.
iii).Radius Gauge: It is used to check the radius of outer and inner surfaces. Every
leave has different radius.
iv).Vertical Height Gauge: It is used to measure the height of work pieces.
v).Thread Gauge: It is used to check the pitch of the threads. It consists of a number
of leaves, pitch of the threads marked on each leaves.
vi).Wire Gauge: It is used to check the diameter of wires and thickness of sheets.
CUTTING TOOLS
These tools are used to remove the materials
1. Hacksaw – It is used of cutting of flats, rods etc. The bl ade of hacksaw is made up of
high carbon steel and frame is made from mild steel. The blade is placed inside the frame
and is tightened with the help of a flange nut. The teeth of hacksaw blades are generally
forward cut. There are two types of hacksaw frames, fixed frames and adjustable frame.
The material to be cut with hacksaw is clamped in a vice. The hacksaw should be moved
perfectly straight and horizontal.
2. Files – It is used to remove material by rubbing it on t he metal. Classification of files.

i) Size – The length of file vary from 4 inch to 14 inch.
ii) Shape – The shapes available are flat, square, round, ha lf-round, triangular
etc.
iii) Cuts – Single and Double Cut.
iv) Grade –
Rough - 20 Teeth per inch
Bastard - 30 Teeth per inch
Second Cut - 40 Teeth per inch
6
Smooth – 50-60 Teeth per inch

Dead Smooth - 100 Teeth per inch
Rough and Bastard files are used for rough cutting, smooth and dead smooth files
are used for finishing work. Files should be used in perfect horizontal position.
Pressure should be applied on the forward stroke only. Work is held in a vice.
3. Chisels – They are used for chipping away the material from the work piece. Commonly
used forms of chisels are flat, cross cut, half round, and diamond point chisels. Flat chisel
is used for chipping a large surface. Crosscut chisel is used for groover. Half round chisel
is used to cut oil-grooves. Diamond point chisel is used for chipping plates.
STRIKING TOOLS
Hammers are the only tools used for striking in fitting shop like chipping, fitting, punching etc.
Main types of hammer
1. Ball Pean Hammer

2. Straight Pean Hammer
3. Cross Pean Hammer
MISCELLANEOUS TOOLS
1. Drill Bit– It is used for making round holes. Twist drill is most commonly used for
making holes on the drill machine.
2. Reamer – It is used to finish the drilled hole to accurate size.
3. Taps – It is used for making internal threads. The tap holder holds tap, normally it comes
in a set of three, taper Tap, Intermediate Tap, and Plug Tap.
4. Die – It is used for cutting external threads. It is held in a diestock, the handle is rotated
by hand and job is held firmly in a vice.
BENCH WORKING PROCESSES
1. Marking – Measurement is performed on the job by measuring instrument and scriber

does marking.
2. Chipping – Material is removed with the help of chisels.
7
3. Sawing – This operation is required to cut the metal in different sizes and shapes by
hacksaw.
4. Filing – This operation is performed with the help of files, pressure should be exerted in
the forward stroke and backward stroke is ideal.
5. Scrapping – This is done for reducing more accurate finish that obtained by filing.
6. Drilling – This is done to produce holes with the help of d rills. It is done on a drilling
machine and job is held in a machine vice. Drill is fixed on the drilling machine,
7. Tapping – This is done to cut the internal threads with the help of tap and tap holder.
8. Dieing – This is done to cut the external threads by the help of die and die holder.
DRILLING MACHINES
There are three types of drilling machines:
1. Bench Drilling Machine: It is used for drilling, reaming, counter sinking and counter
boring etc.
2. Hand Drilling Machine: It is used for making small holes. It is pressed from the handle
with left hand while crank is rotated with right hand.
3. Portable Drilling Machine: It is compact and small in size; it can be brought near to the
work place for drilling medium size holes.
4. Radial Drilling Machine: It is used for drilling large size holes, can be moved in
different directions.
SCREW THREADS
(i) British standard Whitworth threads (BSW): The thread is generally used on bolts
and nuts ‘V’ shape having an angle of 60º.
(ii) Metric Threads: ‘V’ shape having an angle of 60º.
(iii)Square Threads: Shape of thread is square used on screw jacks.
8
(iv) Acme Threads: These threads are stronger than square threads having an angle of 29º,
they are used on lead screw shaft of Lathe.
To Make Right Angle Fitting Job
1. Objective: - Exercise involving marking, Cutting, Filing, Drilling and Tapping on a M.S.
Flat.
2. Tools and equipment used: - Bench vice, Hacksaw. Files. Scriber, Steel rule, Try
square, Hammer, Surface plate, Angle Plate, Surface gauge, Drills, Taps, Vernier
caliper, Centre punch, Drilling machine.
3. Materials required: - Mild steel flat.
4. Drawing: - See Diagrams
5. Procedure:-
Ex I: - To make Rectangular job 100 x 48 mm.

To make a part # 1
1. Mark the M.S flat 100 x 6 x 48 mm (Three pieces) and cut the metal pieces with Hacksaw,
clamping in a Bench vice.
2. File all the four sides at right angle, check with try square.
3. Cut extra metal and file to accurate 100 x 48 mm rectangular piece. Finish the surface
with smooth file keeping tolerance ± 0.5 mm; check the dimension with vernier caliper.
4. Finish the flat sides of the piece also by filing procedure.
5. Mark parallel lines at 12.5 mm distance on each side of the centre on a finished
rectangular piece of 100 x 48 mm as shown in diagram.
6. Take a point at 20 mm depth for making V cut.
7.Cut with hacksaw outer side of marked lines to remove V piece on one side.
8. File the cut ‘V’ to bring it to accurate dimensions
9
9. Mark parallel lines on both sides of center widthwise at 14 mm distance from center on
another finished side having 48 mm width and a line 10 mm deep and mark the line.
10. Punch mark at inside the marked lines and use Shaper machine to remove the inside
material to make female mating part.
11. File the cut to bring it to the accurate dimensions, check angles with try square.
To make a part # 2
1. Mark parallel lines on both sides of center lengthwise at 14 mm distance from center on
another finished rectangular piece 48 x 30 mm and a line 10 mm widthwise and mark a
line.
2. Punch mark outside the marked lines and use the hand hacksaw to cut the extra outside
material to make the male mating part.
3. File the cut to bring it to the accurate dimensions, check angles with try square.
To make a part # 3
1. Mark parallel lines on both sides of center lengthwise at 12.5 mm distance from center on
another finished rectangular piece 48 x 35 mm and a line 20 mm widthwise and mark a line.
2. Take the center point on the edge of this side and make V mark by joining it with depth
line where it meets parallel lines.
3. Punch mark outside the marked lines and use the hand hacksaw to cut the extra outside
material to make the “V” male mating part.
4. File the cut to bring it to the accurate dimensions, check angles with try square
Fitting Check of three Parts
2. Fit the part 2 and 3 into part 1 after filing to accurate dimensions of fitting clearance 0.1mm
3. Check for square ness of the fitting male & female parts.
4. Finish the job with a smooth file.
Ex V: - To make internal Threads

1. Mark the point with centre punch, drill hole (M10 for 8 x 1.25 mm) tapping as shown in
diagram.
2. Fix the taper tap in a Tap Holder, Clamp the Job in a bench vice, Insert Tap in a drilled
hole, hold perpendicular and rotate chock wise to start threading.
3. Apply little Lubricating oil on cutting operation, on each half turn forward, Turn the tap
backward quarter turn, to break the cutting chips.
4. Repeat with threading operation with intermediate and finally with bottoming Tap.
5. Remove the burrs with a file.
10
Safety Precaution
1. Grip the Job in the vice properly.

2. Always move the hacksaw in perfect straight and horizontal position.
3. Hacksaw blade should the fixed in proper direction and tightened sufficiently with correct
tension.
4. Use water as a coolant while sawing.
5. Hold the chisel firmly while chipping
6. Drill the holes centralizing on pop Marks, give gradual feed.
7. Check the dimension time to time carefully, check with Try square and vernier cliper.
8. Tap should be held perpendicular and rotated every half turn forward, reverse quarter turn,
backward.
9. Use lubricating oil during tapping.
Fig: Fitting Job with Three peices
11
WORKSHOP PRACTICE MANUAL (ELECTRIC SHOP)
ELECTRIC WORKSHOP
1
SAFETY PRECAUTIONS
- Always wear a rubber sole closed shoe, while performing experiments.
- Wooden board should be kept under the feet while working on live supply.
- Connect the circuit as given in the circuit diagram.
- Don’t switch on the supply without getting the circuit checked in series.
- Don’t touch the bare joints or terminals.
- Follow the procedure given it the manual strictly to avoid any accident.
- Never touch any bare conductor.
- During repairing electrical appliances should be disconnected from power supply.
- Never disconnect a plug point by pulling the flexible wires.
- In case of electric fire, power supply main switch be disconnected immediately.
- Never use water to extinguish fire. Use sand or CTC fire extinguisher.
- Proper earth must be provided.
- Before replacing burnt fuse, main switch should be put off.
- Never give supply to any point unless you know that nobody is working on line.
- Safety belt should be used while working on poles.
- Electrical appliances should be insulated properly.
1. Be Safety Conscious
Working with electrical circuits can be dangerous if you don’t take certain safety precautions.
Electrical shock can not only injure you but also kill you. Practice safety when working on any
circuit and slow down! When you hurry through a project, there is a greater chance for an
accident to occur.
2. Shut the Power Off

Always shut off the power to a circuit or device that you will be working on. This is the first
thing you should do before working on any electrical circuit. I don’t know anyone who has
been shocked by a circuit that is not energized.
3. Test the Circuit

After turning a circuit off, it's a good idea to check it with a tester to be sure that, indeed, it is
off. Never assume that the circuit is off.
2
4. Ladders
Ladders are necessary to accomplish some electrical jobs. Never use an aluminum ladder on
any electrical project. Always use an insulated fiberglass ladder to keep you safe.
5. Wet Locations
Avoid wet areas when working with or on anything electrical. If there is a reason that you have
to be in that situation, wear rubber boots and gloves to lesson your chance of getting shocked.
Don't forget to dry your hands before grabbing any cord to plug it in or unplug it.
3
INTRODUCTION:
ELECTRICAL: Electrical is an essential need of our daily life. It is widely used for domestic as
well as industrial purposes. So it is necessary for the engineering students work. In electrical
shop knowledge is given about the electricity filed of its application, electrical instruments,
domestic & industrial wiring, electrical goods used, symbol & precaution to be kept in mind.
ELECTRONICS’’ electronics is the field of manipulating electrical current & voltage using
passive or active components that are connected together to create circuits. Electronics circuit
rang from a simple load resistor that converts a current to a voltage to computer central-
processing units (CPU) that contain more than a million transistors.
TOOLS:
1. TEST PEN OR LINE TESTER: Test pen has the following function:-
To check the supply.
Loosing or tightening small screw.
It is a very common tool used in electrical shop. A small bulb is fitted inside a transparent
handle. When checking the supply the blade is touched to the point & the fingertip is placed on
the backside of the handle. If the bulb glues, it shows that electrical current is flowing through
the wire.
 COMBINATION PLIER: It is made of steel. It is the combination of cutter & holder.

It is used for holding, twisting & cutting of wire.
 SCREW DRIVER: Screw driver consist of the following parts:- (1) handle (2) blade.
Handle is made up of plastic or wood blade is made of steel. The top of the blade is
flattened screw driver is used to loosen or tighten the screw.
 POCKER: Pocker is a sharp edge, tool used to make holes in wood. Holes are made for
nails or screws.
 WIRE CUTTER OR NIPPER: It is made of steel and has cutter. It is used for cutting
of wires.
 LONG NOSE PLIER: Nose plier is made of steel. They have a cutter for cutting thin
wires. It is used for holding, twisting and cutting wire. Preparing looks and jointing of
wires.
 BALL PEEN HAMMER: It is made of mild steel having ball on top and face at bottom,
provided with wooden handle. It is used to break the brick, riveting, grooving purpose
and fixing the nails.
 CROSS PEEN HAMMER: It is made of mild steel having cross shape on top and face
at bottom with wooden handle. It is used for fixing clip and nails and making gitties hole
in wall.
4
 HACKSAW: It is made of frame, blade and handle. The blade is fixed in the frame. It is
used for cutting conduit pipe, G.I. pipes and other small metallic materials.
 STANDARD WIRE GAUGE: It is a thin circular steel plate having number of slots on
its circumference. It is used to find the gauge of wire.
 HAND DRILL MACHINE: It is made of wooden handle. It has gear, chuck and jaw. It
is made of cast iron and steel. It is used for making holes in wooden and metallic objects with
twist drill bit.
 ELECTRIC SOLDERING IRON: It consist of an oval copper bit fixed to an iron rod.
It is heated by an electric element. It is used for soldering wires to small joints and commutator
segments.
 WIRE STRIPPER: It is used for remove the insulation from wire.
INTRODUCTION TO ELECTRICAL WIRING
TYPES OF WIRING
a) Cleat Wiring: Cleat wiring is used for temporary

purposes. Wooden or porcelain are used at small distances.
PVC or VIR wires are used for this type of wiring.
This system is suitable for temporary installation
such as marriage and other functions.
b) TRS or CTS or Batten Wiring: In batten wiring,

the wires are covered with tough rubber and are fixed on
wooden batten. Joint clips are used to hold wires. Wooden
batten is used on gutties inserted in the walls.
c) Casing and Capping Wiring: In old days it was

the most used type of wiring. Wire are placed in the
grooves provided on the casing. It is covered with a strip
5
known as capping, caring is fixed on the walls with the help of gutties and scress.
d) Conduit Wiring: In this system, wires are enclosed in conduit pipe to give the wires
mechanical protection. Fire risks are also avoided in this system of wiring. This system is applied
in two ways:
Surface conduit wiring: In this system the pipes are fixed over the surface of walls
and are visible. Surface conduit wiring is easy to install but is less safe to mechanical injuries as
compared to concealed conduit wiring.
Concealed Conduit/Underground Wiring: In concealed conduit wiring the conduit
pipes are buried inside the walls. Grooves are made as per the circuit of the wiring on the wall
with the help of chisel. Pipes, bends and junction box are placed in the grooves and then covered
with cement.
Basic Electrical Terms
AC and DC: Abbreviations for alternating current and direct current respectively.
Current - A movement of electricity analogous to the flow of a stream of water.
Direct Current - An electric current flowing in one direction only (i.e. current produced
using a battery).
6
Alternating Current - a periodic electric current that reverses its direction at regular
intervals.
Amp or Ampere: The unit of intensity of electrical current (the measure of electrical flow), is
abbreviated a or A.
Circuit Breaker: A device designed to open and close a circuit by non-automatic means and to
open the circuit automatically on a predetermined over current without damaging itself when
operated according to its rating.
Circuit: A complete path from the energy source through conducting bodies and back to the
energy source.
Conductor: a substance or body capable of transmitting electricity

Fuse: An over current protective device with a circuit opening part that is heated and broken by
the passage of an over current through it.
Kilowatt-hour: Work done at the steady rate equivalent to 1000 watts in one hour. Power
utility companies’ base their billing upon the number of kilowatt-hours (KWH) consumed.
Lamp: A general term for various devices for artificially producing light.
Ohm: The unit of electrical resistance abbreviated with the symbol omega, W.
Resistance is the opposition offered by a substance to the passage of electrical current.
Ohm's Law: A statement of the relationship, discovered by the German scientist G. S. Ohm,
between the voltage, amperage and resistance of a circuit. It states the voltage of a circuit in
volts is equal to the product of the amperage in amperes and the resistance in ohms. E=IR
Over current: Any current in excess of the rated current. It may result from overload, short
circuit or ground fault.
Overload: Operation in excess of normal full- load rating or rated ampacity which could cause
damage or dangerous overheating if continued for a sufficient time. A fault, such as a short
circuit or ground fault, is not an overload. See "Over Current".
Single Phase: a system of alternating current power where the phase relationship between
ungrounded conductors is either 0 or 10 degrees. OR if there is one Phase wire one neutral and
third one is earth, the system is called single Phase.
Three Phase: a system of alternating current power where the phase relationship between
ungrounded conductors is either 0 or 120 degrees. OR if there are three Phase wires one neutral
and fifth one is earth, the system is called three Phase.
7
Transformer: An apparatus for converting an alternating electrical current from a high to a low
potential (voltage) or vice versa. Uses of transformers include but are not limited to the
conversion of utility transmission voltage to the voltage of the premises wiring system and
conversion of voltage for use with chimes, alarm systems and low-voltage lighting.
Transformers can also be used to compensate for minor variations equipment voltage
requirements. Transformers only change voltage and amperage.
Volt: the unit of electromotive force or Voltage, the measure of electrical pressure, is
abbreviated v.
Watt: the unit of power or rate of work represented by a current of one ampere under a pressure
of one volt (abbreviated w or W). The horsepower is approximately equal to 745.7 watts.
Wattage ratings of lamps actually measure the power consumption not the illuminating
capability.
The Wonder of Electricity
Electricity is the set of physical phenomena associated with the presence and flow of electric
charge. Electricity gives a wide variety of well-known effects, such as lightning, static
electricity, electromagnetic induction and electrical current. In addition, electricity permits the
creation and reception of electromagnetic radiation such as radio waves.
How Electricity Is Generated
Turbine Generator
A generator is a device that converts mechanical energy into electrical energy. The process is
based on the relationship between magnetism and electricity. In 1831, scientist Michael Faraday
discovered that when a magnet is moved inside a coil of wire, electrical current flows in the
wire.
A typical generator at a power plant uses an electromagnet — a magnet produced by electricity

— not a traditional magnet. The generator has a series of insulated coils of wire that form a
8
stationary cylinder. This cylinder surrounds a rotary electromagnetic shaft. When the
electromagnetic shaft rotates, it induces a small electric current in each section of the wire coil.
Each section of the wire becomes a small, separate electric conductor. The small currents of
individual sections are added together to form one large current. This current is the electric
power that is transmitted from the power company to the consumer.
An electric utility power station uses either a turbine, engine, water wheel, or other similar
machine to drive an electric generator — a device that converts mechanical or chemical energy
to electricity. Steam turbines, internal-combustion engines, gas combustion turbines, water
turbines, and wind turbines are the most common methods to generate electricity.
Steam turbine power plants powered by coal and nuclear energy produce about 70% of the
electricity used in the United States. These plants are about 35% efficient. That means that for
every 100 units of primary heat energy that go into a plant, only 35 units are converted to
useable electrical energy. Most of the electricity in the United States is produced using steam
turbines.
According to the Federal Ministry of Planning, Development and Reforms of Pakistan, the
power production of Pakistan is dependent on a number of sources. The graph shows Pakistan’s
energy mix. Pakistan is producing 11% of its energy through Hydroelectric Power plants, 33%
comes from the plants which are running on oil. 6% is from coal fired power plants. 48.2% is
from indigenous (local) gas.1.7% is from nuclear power plants and 0.1% is imported
Electricity.
A turbine converts the kinetic energy of a moving fluid (liquid or gas) to mechanical energy. In
a steam turbine, steam is forced against a series of blades mounted on a shaft, thus rotating the
shaft connected to the generator. The generator, in turn, converts its mechanical energy to
electrical energy based on the relationship between magnetism and electricity.
9
In steam turbines powered by fossil fuels, such as coal, petroleum (oil), and natural gas, the fuel
is burned in a furnace to heat water in a boiler to produce steam.
More on Electrical Generation and Transmission
10
Electrical Principles and Application Section
The "symbol" given for each quantity is the standard alphabetical letter used to represent that
quantity in an algebraic equation. Standardized letters like these are common in the disciplines
of physics and engineering, and are internationally recognized. The "unit abbreviation" for each
quantity represents the alphabetical symbol used as a shorthand notation for its particular unit of
measurement. And, yes, that strange-looking "horseshoe" symbol is the capital Greek letter Ω.
Each unit of measurement is named after a famous experimenter in electricity: The amp after
the Frenchman Andre M. Ampere, the volt after the Italian Alessandro Volta, and the ohm after
the German Georg Simon Ohm.
Magnets and Electricity
Magnetic Field around a Bar Magnet
11
The spinning of the electrons around the nucleus of an atom creates a tiny magnetic field. Most
objects are not magnetic because their electrons spin in different, random directions, and cancel
out each other.
Magnets are different; the molecules in magnets are arranged so that their electrons spin in the
same direction. This arrangement of atoms creates two poles in a magnet, a North-seeking pole
and a South-seeking pole.
Magnets Have Magnetic Fields

The magnetic force in a magnet flows from the North pole to the South pole. This creates a
magnetic field around a magnet. Have you ever held two magnets close to each other?
They don't act like most objects.
If you try to push the South poles together, they repel each other. Two North poles also repel
each other. Turn one magnet around, and the North (N) and the South (S) poles are attracted to
each other. Just like protons and electrons — opposites attract.
Magnetic Fields Can Be Used To Make Electricity

Properties of magnets can be used to make electricity. Moving magnetic fields can pull and
push electrons. Metals such as copper have electrons that are loosely held. So electrons in
copper wires can easily be pushed from their shells by moving magnets. By using moving
magnets and copper wire together, electric generators create electricity. Electric generators
essentially convert kinetic energy (the energy of motion) into electrical energy.
Difference between Wire & Cable

Wire and cable are two terms that are used in electrical and communication fields. They are often
confused, but in fact, they are quite different.
A wire is a single conductor (material most commonly being copper or aluminium) while cable
is two or more insulated wires wrapped in one jacket. Multiple conductors that have no
12
insulation around would be classified as a single conductor.
Types of Electrical Wires

There are two main types of wires: solid or stranded.
A solid wire is a single conductor that is either bare or
insulated by a protective colored sheath. It offers low
resistance and are perfect for use in higher frequencies.
When inside a covering there are many thin strands of wires twisted together, it is called a
stranded wire. Stranded wires are used where flexibility is important because of which the wire
can be used for a longer period. This type of wire have larger cross-sectional area than solid
wires for the same current carrying capacity.
Types of Electrical Cables

there are various types of cables, including twisted pair cable, coaxial cable, multi conductor
cable and fiber optic cable.
1. Twisted pair cable – Twisted pair cabling comes in two varieties: shielded and unshielded. A
twisted pair cable has two cables that are twisted across each other. Twisting can avoid noise that
produced by magnetic coupling, so this type of cable is best suited for carrying signals. It is
generally used in telecommunication and data communication.
2. Multi-conductor cable – Multi conductor cable has two or more conductors that are insulated
from each other. Their purpose is to protect signal integrity by reducing hum, noise and
crosstalk. Applications include computers, communications, instrumentation, sound, control,
audio, and data transmission. Both multi
conductor and twisted pair cables are called
balanced line configuration cables.
3. Coaxial cable – Coaxial cable is composed of

an inner solid conductor surrounded by a
paralleled outer foil conductor that is protected by
an insulating layer. The two conductors are
13
separated from each other by an insulating dielectric. Coaxial cables are generally used in TV
Cable. It is called an unbalanced line as the signal on the two conductors is not same, which
result in interference but the performance is more stable than a twisted pair cable. Used for radio
frequency signals, for example in cable television distribution systems.
4. Fiber optics cable: – This kind of cable transmits signals by a bundle of glass threads. Fiber
optic cables have a much greater bandwidth than metal cables, which means they can carry more
data. They are also less susceptible to interference. For these two reasons, fiber optic cables are
increasingly being used instead of traditional copper cables despite that they are expensive
5. Direct-buried cable: (DBC) is a kind of

communications or transmissions which is
especially designed to be buried under the
ground without any kind of extra covering,
sheathing, or piping to protect it.
14
Market names of wires:
Wires are commonly available in the market. The designations commonly used for wires is easy
to understand.
3/0.029 means wire has three copper wires together as a conductor and 0.029 inch is the
diameter of individual wire.
15
EXPERIMENT NO.01
Wiring For Two Lamps (Bulbs) With Independent Switch Controls
Aim: - To give connection to two lights, controlled With Independent Switch Controls
Tools required: -
1. Screw driver
2. Cutting pliers
3. Insulation Tape
4. Insulation remover
5. Phase Tester
Material required: -
1. PVC wiring board
2. Wire 3/0.029
3. Electrical bulbs 2 No
4. One-way switch 1No
5. Batten lamp holders 2 No
6. Two pin shoe 1 Nos.
16
Procedure:
1. First of all collect all the tools and materials needed and arrange them according to the circuit
diagram shown
2. Cut the wire pieces as needed using wire cutter and remove insulation from the ends to make
electrical connection to the terminal of switches and holders.
3. Use appropriate screw driver to unscrew the screws from the terminals of switches and
holders.
4. Join the wires accordingly following the circuit diagram.
5. Fit the bulbs in the holders
6. Wiring connections are checked and supply is given to check the circuit.
Safety precautions:
1. Electricity has no respect for ignorance. Do not apply voltage or turn-on any device until it
has been properly checked.
2. Care should be taken from electrical shocks.
3. Don’t touch the connection points.
4. Avoid loose connection.
5. Don’t work at damped areas and with wet clothing.
6. Handle the lamp carefully.
Result:
Connections are given to two bulbs controlled by the two independent switches and Tested.
17
EXPERIMENT NO: 02
ONE LAMP CONTROLLED BY TWO TWO-WAY SWITCHES (STAIR CASE
CONNECTION)
Aim: - to give connections to one lamp controlled by two two-way switches.

Tools required: -
1. Screw driver
2. Cutting pliers
3. Ball peen hammer
4. Insulation remover
5. Tester
Material required: -
1. PVC wiring board

2. Wire 3/0.029
3. Electrical bulb 1 No
4. Two -way switches 2Nos
5. Lamp holder 1 No
6. To pin shoe 1 Nos.
18
Procedure:
1. First of all collect all the tools and materials needed and arrange them according to the circuit
diagram shown
2. Cut the wire pieces as needed using wire cutter and remove insulation from the ends to make
electrical connection to the terminal of switches and holders.
3. Use appropriate screw driver to unscrew the screws from the terminals of switches and
holders.
4. Join the wires accordingly following the circuit diagram.
5. Fit the bulbs in the holders
6. Wiring connections are checked and supply is given to check the circuit.
Safety precautions:
1. Electricity has no respect for ignorance. Do not apply voltage or turn-on any device until it
has been properly checked.
2. Care should be taken from electrical shocks.
3. Don’t touch the connection points.
4. Avoid loose connection.
5. Don’t work at damped areas and with wet clothing.
6. Handle the lamp carefully.
Result: - Connections are given to one lamp controlled by two two-way switches and tested.
19
EXPERIMENT NO.03
OBJECTIVE: To connect two lamps in series &control by one way switch.
TOOL USED: Knife, combination plier, screw driver, poker, line tester, wire stripper, hacksaw
& ball /cross pean hammer.
Safety precautions: PRECAUTION:
a) Connection must be tight & right as per circuit dig.

b) Live conductor should be go through switch.
c) After removed the insulation from wires, wire conductors should be twisted with the
help of plier.
d) Always check in series, do not connect with the direct supply.
e) For safety, should be used circuit breaker/ fuse in the circuit as per rating.
f) Tools should be insulated.
g) Earth must be provided. Electricity has no respect for ignorance. Do not apply voltage or
turn-on any device until it has been properly checked.
h) Care should be taken from electrical shocks.
i) Don’t touch the connection points.
j) Don’t work at damped areas and with wet clothing.
k) Handle the lamp carefully.
Diagram: Series Connection of Lamps and controlled by one switch.
20
PROCEDURE:-
a) Take the casing (as per requirement), wooden blocks, wooden round blocks, fixed on the
wiring board with batten nails and wooden screws with the help of screw driver and hammer as
per dimension.
b) Now as per circuit diagram wires installed. Firstly, no. 2 terminal of batten holder (lamp
-1) & no.1 terminal of batten holder (lamp-2) connected to each other with help of wires.
c) Neutral wire connected with the no -1 terminal of lamp-1
d) Phase wire connected through one way switch with batten holder (second terminal
) of lamp .-2
e) Batten holders & Bakelite fixed one round block & wooden block with screws.
Capping is fitted on casing two lamps fixed on battle holders.
Result: - job checked in serious lamps glows dim & then checked with the direct supply, both
lamps has glows dim, because both lamp are connected in series.
21
Same procedure can be done using diagram given above for parallel Connection of Lamps:
22
Workshop Practice Manual (Carpentary Shop)
CARPENTARY WORKSHOP
SAFETY PRECAUTIONS
 While working keep your mind & eyes on the job & do not indulge in talking.
 Avoid using loose clothing.
 There should be no sharp tools in your pocket.
 The tools being used should be well sharpened.
 The floor of the shop should be well cleaned, free from scrap & wooden pieces carrying
nails etc.
 Safety guard provide on the machines should be in proper position & well secured.
 The PPE’s (Personal Protective Equipment) provided to you must be used.
 While working on a band saw it should be ensured that the guides are properly adjusted.
 Feed the stock directly the moving hand & don’t press from sides.
 Cutting should be start only after the saw attains the full Speed.
 Turning tools should be held firmly. Use goggles while turning & sawing.
INTRODUCTION
Carpentry may be defined as the process of making wooden components. It starts from a
marketable form of wood and ends with finished products. It deals with the building work,
furniture, cabinet making, etc. Joinery, i.e., preparation of joints is one of the important
operations in all woodworks. It deals with the specific work of carpenter like making different
types of joints to form a finished product.
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 strong, the timber must be so cut, that the grains run parallel to the
length.
Timber sizes
Timber sold in the market is in various sizes and shapes. The following are the common shapes
and sizes.
a. Log ‐ the trunk of the tree which is free from branches.
b. Balk ‐ the log, sawn to have roughly square cross section.
c. Post ‐ A timber piece, round or square in cross section, having its diameter or side from 175 to
300mm.
d. Plank ‐ A 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.
e. Board ‐ A sawn timber piece, below 175 mm in width and 30 to 50 mm in thickness.
f. Reapers ‐ Sawn timber pieces of assorted and non‐standard sizes, which do not confirm to the
above shapes and sizes.
Classification of Timber
1
According to the manner of growth of trees. Timber can be classified as

1. Exogenous or outward growing
2. Endogenous or inward growing
1. Exogenous of outward growing trees:
In exogenous trees the growth takes place from the centre y the addition of concentric layers of
fresh wood every year, known as annual rings. These varieties of trees are suitable for building
and other engineering uses the exogenous trees are again classified as
 Conifers or ever green trees
 Deciduous or broad leaf trees
2. Endogenous Trees:
Wood suitable for construction and other engineering purposes is called timber. Woods in
general are divided into two broad categories: Soft woods and hard woods.
., but it is highly durable. Another classification of woods is based on the name of the trees like
teak, babul, shisham, neem, kair, chir, etc.
a. Soft Wood
A soft wood is light in weight and light colored. They may have distict annual rings but the
medullar rays( Radial lines ) are not visible and the color of the sap wood (outer layer) is not
distinctive from the heart wood(inner layer). These woods cannot resist stresses developed across
their fibers; hence not suitable for wood working. Soft woods are obtained from conifers, kair,
deodar, chir, walnut and seemal
b. Hard Wood
In this type of wood the annual rings are compact and thin and the dedullar rays(radial lines) are
visible in most cases as shown in the Figurs 1. Hard woods are nearly equally strong both along
and across the fibers. Hard wood is the material used for wood working. Woods obtained from
teak, sal, oak, shisham, beach, ash mango, neem and babul are known as hard wood
c. Plywood:
It consists of more than three layers. Middle layer is called core which is thick and not of good
quality. The top and bottom are called as face plys which is glued on the core at top and bottom.
The grains of adjacent layers are kept perpendicular to each other.
Types of Ply – Ply 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.
2
4. Possesses bottom strength then solid wood of same thickness.
DEFECTS IN TIMBER
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 defects – Wood being a product of nature is subjected of natural defects, some of them
are explained below:
 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
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.
Wind shakes or Cup shaker: The separation of annual rings is called wind shake
or cup shake. These defects are common in lines.
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.
 Knots: Knot represent irregularity in the body of a tree which interrupts 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:
Dead knots: When the separation of benches or herbs 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.
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.
According to the shapes knot can be classified as shown in fig.
 CHECKS
They are small separations of the wood fibers in a longitudinal Wood Defects direction,
not penetrating as far as the opposite or adjoining side of a piece of sawn timber; they
usually result from strains developing during seasoning; Surface (or Seasoning) Checks,
and End (or Heart) Checks are distinguished.
 SPLIT:
3
It is a longitudinal separation of the fibers which extends to the opposite face or adjoining
edge of a piece of sawn timber.
 WANE:
Is the lack of wood on any face or edge of a piece of sawn timber, usually caused by a
portion of the original rounded surface of a long remaining on the piece; bark may or may
not be present
SEASONING OF WOOD
A newly felled tree contains considerable moisture content. If this is not removed, the timber is
likely to wrap, shrink, crack or decay. Seasoning is the art of extracting the moisture content
under controlled conditions, at a uniform rate, from all the parts of the timber. Only seasoned
wood should be used for all carpentry works. Seasoning makes the wood resilient and lighter.
Further, it ensures that the wood will not distort after it is made into an object. By reducing
moisture content, the strength, elasticity and durability properties are developed. 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, cracking and
distortion etc. To overcome these issues, seasoning is done. After seasoning the percentage of
4
moisture is reduced to 10-20%.
Types of Seasoning
(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 kils. 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.
(iv) Electric Seasoning: In the method of electrical seasoning timber is subjected to

high frequency alternating currents. The resistance of timber against electricity is
measured at every interval of time. When the required resistance is reached
seasoning, process is stopped because resistance of timber increases by reducing
moisture content in it. It is also called as rapid seasoning and it is uneconomical.
(v) Seasoning by Boiling: Seasoning of timber is also achieved by boiling it in

water for 3 to 4 hours. After boiling timber is allowed to drying. For large
quantity of timber boiling is difficult so, sometimes hot steam is passed through
timber logs in enclosed room. It also gives good results. The boiling or steaming
process develops the strength and elasticity of timber but economically it is of
heavier cost.
(vi) Chemical Seasoning: In case of chemical seasoning, timber is stored in suitable

salt solution for some time. The salt solution used has the tendency to absorb
water from the timber. So, the moisture content is removed and then timber is
allowed to drying. It affects the strength of the timber.
Parts of the Trunk:
Inside the trunk of a tree are a number of rings. Each year of the tree's life a new ring is added so
many people refer to them as the annual rings. The rings are actually made up of different parts:
5
Bark:
The outside layer of the trunk, branches and twigs of trees. The bark serves as a protective layer
for the more delicate inside wood of the tree. Trees actually have inner bark and outer bark -- the
inner layer of bark is made up of living cells and the outer layer is made of dead cells, sort of like
our fingernails. The scientific name for the inner layer of bark is Phloem. The main job of this
inner layer is to carry sap full of sugar from the leaves to the rest of the tree.
Cambium:
The thin layer of living cells just inside the bark is called cambium. It is the part of the tree that
makes new cells allowing the tree to grow wider each year.
Sapwood (Xylem):
The scientific name for sapwood is xylem. It is made up of a network of living cells that bring
water and nutrients up from the roots to the branches, twigs and leaves. It is the youngest wood
of the tree -- over the years, the inner layers of sapwood die and become heartwood.
Heartwood:
The heartwood is dead sapwood in the center of the trunk. It is the hardest wood of the tree
giving it support and strength. It is usually darker in colour than the sapwood.
Pith:
Pith is the tiny dark spot of spongy living cells right in the center of the tree trunk. Essential
nutrients are carried up through the pith. Its placement right in the center means it is the most
protected from damage by insects, the wind or animals.
Seasoning of Wood
Characteristics of Good Timber
The good timber must possess the following characteristics

1. It should have minimum moisture content, i.e., the timber should be well seasoned.
6
2. The grains of wood should be straight and long.

3. It must retain its straightness after seasoning.
4. It should produce near metallic sound on hammering.
5. It should be free from knots or cracks.
6. It should be of uniform color, throughout the part of the wood.
7. It should respond well to the finishing and polishing operations.
8. During driving the nails and screw, it should not split easily.
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.
Steel rule and Steel tape
Steel rule 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 tape is used for large
measurements, such as marking on boards and checking the overall dimensions of the work.
Figure 2.1: Steel rule and Steel tape

2.3.2 Marking gauge
It 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
7
End are sharp enough to make a very fine line. A mortise gauge 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 2.2: Marking gauges
Try square
It is used for marking and testing the quality of being a perfect Square or at 90o 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 try square used in the fitting shop.
Figure 2.3: Try square
Compass and divider

Compass and divider, are used for marking arcs and circles on the planed surfaces of the wood.
Scribe r or marking knife

It 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.
Bevel
It is used for laying out 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 try square. 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.
8
Figure 2.4: Compass and Divider Figure 2.5: Scriber and Bevel
HOLDING TOOLS
Carpenter's vice
Figure 2.6 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 2.6: Carpenters vice

PLANING TOOLS
Planning is the operation used to produce flat surfaces on wood. A plane is a hand tool used for
this 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.
Jack plane
It 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.
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WORKSHOP PRACTICE Lab manual
Smoothing plane
It 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.
Rebate plane
It 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.
Plough plane
It is used to cut grooves, which are used to fix panels in a door. Figure 2.9 shows the various
types of planes mentioned above.
Figure 2.9: Types of planes
Sharpening Tool:
Water Stone: It is a rectangular piece of stone generally kept in a wooden base. It is used
to re-sharpen the chisels, bits, plane blades and other tools, white sharpening water is
sprinkled on the stone.
CUTTING TOOLS
Saws
A saw is used to cut wood into pieces. There are different types of saws, designed to suit
different purposes. A saw is specified by the length of its toothed edge.
Cross cut or hand saw
It 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.
10
11
Rip saw
It is used for cutting the stock along the grains. The cutting edge of this saw makes a steeper
angle, i.e., about 60o‹ whereas that of crosscut saw makes an angle of 45 o‹ with the surface of the
stock.
Tenon saw
It 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 back
saw. In this, the teeth are shaped like those of cross cut saw.
Compass saw
It 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.
Figure 2.10: Types of saws
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.
These are made of forged steel or tool steel blades.
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WORKSHOP PRACTICE Lab manual
Figure 2.11: Parts of chisel
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 2.12 a.
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.
Mortise chisel
It is used for cutting mortises and chipping inside holes, etc. The cross-section of the mortise
chisel is proportioned to withstand heavy blows during mortising. Further, the cross section is
made stronger near the shank.
a. Firmer b. Dovetail c. Mortise
Figure 2.12: Types of chisels
DRILLING AND BORING TOOLS
Carpenter's brace
It 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.
13
Auger bit
It 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 o n the brace. The helical flutes on
the surface carry the chips to the outer surface.
Hand drill
Carpenter's brace is used to make relatively large size holes; whereas hand drill 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.
Gimlet
It has cutting edges like a twist drill. It is used for drilling large diameter holes with the hand
pressure.
Figure 2.13: Drilling tools

MISCELLANEOUS TOOLS
Mallet
It 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.
Pincer
It is made of two forged steel arms with a hinged joint and is used for pulling out small nails
from wood. The inner faces of the pincer 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.
Claw hammer
It has a striking flat face at one end and the claw at the other, as shown in figure. The face is used
to drive nails into wood and for other striking purposes and the claw for extracting relatively
14
large nails out of wood. It is made of cast steel and weighs from 0.25 kg to 0.75 kg.
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 figure. The length of a screw driver is
determined by the length of the blade. As the length of the blade increases, the width and
thickness of the tip also increase.
Wood rasp file

It is a finishing tool used to make the wood surface smooth, remove sharp edges, finish fillets
and other interior surfaces. Sharp cutting teeth are provided on its surface for the purpose. This
file is exclusively used in wood work.
Bradawl
It is a hand operated tool, used to bore small holes for starting a screw or large nail.
a. Mallet b. Pincer c. Claw hammer d. Bradawl
e. Wood rasp file f. Screw driver
Figure 2.14: Miscellaneous tools

WOOD JOINTS
There are many kinds of joints used to connect wood stock. Each joint has a definite use and
requires lay in out, cutting them together. The strength of the joint depends upon amount of
contact area. If a particular joint does not have much contact area, then it must be reinforced with
nails, screws or dowels. The figure 2.15 shows some commonly used wood joints.
15
a. Butt b. Dowell c. Dado d. Rabbet
e. Lap f. Mortise and tenon g. Miter
Figure 2.15: Common wood joints

Lap joints
In lap joints, an equal amount of wood is removed from each piece, as shown in figure 2.16. Lap
joints are easy to layout, using a try square and a marking gauge. 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.
Figure 2.16: Lap joints
Mortise and Tenon Joints
It is used in the construction of quality furniture. It results in a strong joint and requires
considerable skill to make it. The following are the stages involved in the work. a. Mark the
mortise and tenon layouts.
16
b. Cut the mortise first by drilling series of holes within the layout line, chiseling out the waste
stock and trimming the corners and sides.
c. Prepare the tenon by cutting and chiseling.
d. Check the tenon size against the mortise that has been prepared and adjust it if necessary.
Figure 2.17: Mortise and Tenon joints

Bridle joint
This is the reverse of mortise and tenon joint in form. The marking out of the joint is the same as
for mortise and tenon joint. This joint is used where the members are of square or near square
section and unsuitable for mortise and tenon joint.
Figure 2.18: Bridle joint
17
Experiment No.01
Objective: To Prepare a “HALF LAP T – JOINT” as per given Drawing.
Tools Used: Steel Rule, Pencil, Try square, Marking Gauge, Rip saw and Tenon saw, Jack
Plane and Smooth Plane, Firmer Chisel, Mallet and Ball peen Hammer
Material Used: Wooden piece of Soft Wood.
Drawing: - See Diagrams
Procedure:-
1. Taken a wooden piece slightly more than given dimension.
2. Fix the job piece in carpentry vice and do planning on width side the help of jack plane and
smoothing with the smooth plane and check flatness and straightness of the work piece with
the help of try square.
3. Same pervious process repeat on adjacent side upto make right angle (i.e. 90o).
4. Make one size (i.e. 30 mm or 40 mm) on the work piece and remove extra material
accordingly with the help of marking gauge, jack plane and smoothing plane.
5. Mark other size (i.e. 30 mm or 40 mm) on the job piece and remove extra material.
6. Mark two pieces each 150 mm in length with the help of pencil, try square and rip saw.
7. Mark on the both job piece as per given dimensions with the help of pencil, try square and
marking gauge.
8. Remove extra material and produce recess on one work piece at one end and middle of the
other job work as per given sketch with the help of rip saw and Tenon saw, firmer chisel and
mallet.
9. Fit the job pieces in the shape of “T=- LAP JOINT”
Safety Precautions
1. Never feed the stock faster than its capacity.
2. Hold the job firmly with clamping devices while working at the machines.
3. Always keep the tools at proper position when not in use. They should not be scrapped on
the wood floor.
4. Keep the floor area free from obstructions.
18
Half Lap T – JOINT
Figure: Drawing “Half Lap T – JOINT. All the dimension are in mm.
19
Experiment No.02
Objective: To prepare a “Cross Lap Joint” as per given Drawing.
Tools Used: Steel Rule, Pencil, Try square, Marking Gauge, Rip saw and Tenon saw, Jack
Plane and Smooth Plane, Firmer Chisel, Mallet and Ball pen Hammer
Material Used: Wooden piece of “Soft Wood”
Procedure:-
1. Taken a wooden piece slightly more than given dimension.

2. Fix the job piece in carpentry vice and do planning on width side the help of jack plane
and smoothing with the smooth plane and check flatness and straightness of the work
piece with the help of try square.
3. Same pervious process repeat on adjacent side upto make right angle (i.e. 900 ).
4. Make one size (i.e. 30 mm or 40 mm) on the work piece and remove extra material
accordingly with the help of marking gauge, jack plane and smoothing plane.
5. Mark other size (i.e. 30 mm or 40 mm) on the job piece and remove extra material.
6. Mark two pieces each 150 mm in length with the help of pencil, try square and rip saw.
7. Mark on the both job piece as per given dimensions with the help of pencil, try square
and marking gauge.
8. Remove extra material and produce recess on the middle of the both work piece as per
given diagram with the help of Rip saw, firmer chisel and mallet.
9. Fit the job pieces in the shape of “CROSS LAP JOINT ”
Safety Precautions

the wood floor.
20
Half Lap Cross Joint
Figure: Half Lap Cross Joint. All the dimension are in mm.
Experiment No.03
21
Objectives: To prepare Mortise and Tenon Joint
Tools Used: Steel ruler, Try square, Measuring tape, Smoothing plane, Mortise and marking
gauge, Rip and Tenon saw, Pencil, Mallet, Ball Peen hammer, Clamping vice, Mortise, Gauge,
and firmer chisel
Materials Used: wood Piece of require dimension
Procedure:
1. Procure mortise and Tenon members of required dimension.

2. Square the piece to the suitable dimension and mark their faces.
3. Now, mark the length of the Tenon, and square a line all around it end at the point, which
is the shoulder. Also mark the width of the Tenon member on the mortise at the point
where they are jointed.
4. Now use a mortises gauge, mark the thickness of the Tenon. Also. Mark width of the
mortises groove on the mortises member (for the face of the members that are to be
flushed). Using the same gauge.
5. In order to avoid tearing of mortises while chiseling. Layout an additional check cut at
both Tenon and mortises members.
6. Saw off the thin pieces of wood along the layout lines already marked, by using Tenon
saw or rip saw.
7. Then trim off any unevenness with a sharp chisel.
8. When working on a plane it should be ensured that the blades are sharp and the cut is
light. Use a push block for all face planning, especially on the short pieces of stock.
Safety Precautions

the wood floor.
22
Figure: Mortise and Tenon Joint. All the dimension are in mm.
Figure: Mortise and Tenon Joint. All the dimension are in mm.
23

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WORKSHOP PRACTICE MANUAL (MACHINE SHOP)

1. Layout and its types

In case of manufacturing units, factory layout may be

4.1. Product or line Layout:

4.2. Process Layout:

4.3. Fixed Position or Location Layout:

4.4. Combined layout:

5. FACTORS INFLUENCING LAYOUT

6. Dynamics Of Plant Layout

1) Increase in the output of the existing product

2) Introduction of a new product and diversification

THE PRINCIPLE PARTS OF LATHE

Five main parts;

Glossary of Lathe Terms

A) Length of the bed.

D) Swing over carriage

Measurements involved in operation performed on Lathe:

Smallest reading on main scale

Zero Errors of Vernier Caliper

The zero error is of two types:

a. Positive zero error; and

Positive Zero Error

Positive Zero Error value= coinciding division X least count

Negative Zero Error

Difference= total no. of divisions – Coinciding division

Here Negative zero error value = 6 x 0.1 = 0.6

Micrometer screw gauge:

𝐏𝐢𝐭𝐜𝐡 𝐨𝐟 𝐬𝐜𝐫𝐞𝐰 𝐠𝐚𝐮𝐠𝐞

The least count of the screw gauge is 0.01mm or .001 cm.

Zero Error for micrometer screw gauge

Positive Zero Error

Negative Zero Error

3. Open the gap between stud and spindle

CUTTING SPEED, FEED AND DEPTH OF CUT:

Lathe Speeds and Feeds.

(b)Another factor to consider when

(b) Rough Cuts.

(c) Finish Cuts.

(b) Rough Cuts.

(c) Finish Cuts.

TYPE OF MILLING MACHINE

(6) ARBOR; It holds and drives different types of milling cutters.

OTHER TOOLS IN MACHINE SHOP

LATHE MACHINE ACCESSORIES & ATTACHMENT

Figure: Diagram of the Workpiece to be prepared

Working Principle of Shaper

Cutting Speed of the Shaper:

NC-CNC Machine Tools

Numerical control or computerized numerical control is a technique of automatically

PHYSICAL PROPERTIES OF METALS

1. Lustre: Lustre is the ability of a metal surface to reflect light rays.

2. Colour: Colour is the property of a metal to show specific surface appearance.

Metals are classified into two categories:

Medium Carbon Steel - Carbon content 0.30 to

iii. Spring Steel – alloy steel used for making springs.

ii). Brass: Alloy of copper and zinc, soft and ductile.

TOOLS USED IN FITTING SHOP

MEASURING AND MARKING TOOLS

iv).Vertical Height Gauge: It is used to measure the height of work pieces.

These tools are used to remove the materials