II Jai Sri Gurudev II

Sri Adichunchanagiri Shikshana Trust®

SJB INSTITUTE OF TECHNOLOGY

BGS Health & Education City, Dr. Vishnuvardhan Road, Kengeri, Bengaluru – 560060

MACHINING
SCIENCE
JIGS & FIXTURES
21ME42

Faculty Name : Uday M

Designation : Assistant Professor
2022-2023
TABLE OF
CONTENT

VISION , MISSION

PO'S, PSO'S & PEO'S

BLOOMS TAXONOMY

OBJECTIVES AND OUTCOMES

COURSE SYLLABUS

LECTURE NOTES
VISION
MISSION

Vision of the Institute

To become a recognized technical education center with global
perspective.

Mission of the Institute

To provide learning opportunities that fosters students ethical
values, intelligent development in science & technology and
social responsibility so that they become sensible and
contributing members of the society.

Vision of the Department

• To become a center of excellence and a platform in diversified
fields for the aspirants in Mechanical Engineering.

Mission of the Department

• To impart comprehensive education in the field of mechanical
engineering to produce highly accomplished graduates
• To endow high profile technical & soft skill trainings to foster
professionalism and ethical values among students
• To inculcate innovative thinking among students through
projects and research work
 02.

Program Specific Outcomes (PSO’s)

PSO1: Apply the Knowledge & Skill of Mechanical Engineering on Design,

Manufacturing and Thermal platforms to address the real life problem of
the society.
PSO2: Design and implement new ideas with the help of CAD/CAM and
Industrial Automation tools.

Program Educational Objectives (PEO’s)

PEO-1: Progress their career as a professional in mechanical engineering
and interdisciplinary fields.
PEO-2: Become successful entrepreneur with social responsibilities and
ethical values.
PEO-3: Pursue higher education and involve in research of allied areas in
mechanical engineering.
 BLOOMS
TAXANOMY

03.
 COURSE
OBJECTIVE

04.
Course objectives

To know the various subtractive machining processes in industries.

To calculate the values of various forces involved in the machining
operations.
To understand and determine tool wear and tool life of different
machining processes.
To know various non-conventional machining and hybrid machining
processes.
To know the design of jigs and fixtures for various industrial/
machining members.

Course outcomes

At the end of the course the student will be able to:

Demonstrate the Conventional CNC machines and advanced

manufacturing process operations
Determine tool life, cutting force, and economy of the machining
process.
Analyze the influence of various parameters on machine tools'
performance.
Select the appropriate machine tools and process, the Jigs, and
fixtures for various applications.
 05
SYLLABUS

MODULE 1:
Introduction to Machining Processes and Machine Tools: Subtractive manufacturing processes
and classifications.
Construction, specification operations of machine tools:– Lathe, Shaping, Milling, Drilling,
Grinding Machine.
Introduction to CNC machines: CNC Lathe, Milling, Drilling, Machine Center.

MODULE 2:
Mechanics of Metal Cutting: Single point turning tool geometry (SPTT) influences the chip
formation mechanisms of the Orthogonal and Oblique cutting process. Cutting Force Analysis
(Orthogonal Cutting):Analysis of machining forces and power requirement, ‘Merchant’s model of
Orthogonal Cutting and Theory of Lee & Shaffer’ Chip Velocity, Velocity relationships (simple
numerical); the influence of cutting temperature on machinability. CuttingFluids: Characteristics
of Cutting fluids, Selections, and applying methods of cutting fluids.

MODULE 3:
Machinability and Tool Life Process of cutting tool failure wears and time relationship, tool wear
index, feed marks, the effect of tool wear on the machined surface, surface finish, machinability,
machinability index/rating, tool life & variables affecting tool life, tool materials. Finishing
Process: Importance of surface finishing processes, Grinding, Abrasive Flow Machining, Honing.
Sanding, Abrasive blasting, Polishing, Lapping. Surface Finishing and Protection: Powder Coating,
Liquid Coating, Electroplating, Galvanizing, Anodizing.

MODULE 4:
Advanced Machining Process; Importance and classification of advanced machining process;
Process principal, process parameters, and application of: - Abrasive Jet Machining (AJW), Water
Jet Machining (WJM), Abrasive Water Jet Machining (AWJM); Ultrasonic Machining
(USM);Electrical Discharge Machining (EDM); Wire Electrical Discharge Machining (WEDM); Electro
Chemical Machining (ECM). Laser Beam Machining (LBM), Electron Beam Machining (EBM), and
Plasma Arc Machining (PAM). Hybrid Machining Process: Importance of hybrid machining
process; Process principal, process parameters, and application of: - Electrochemical Discharge
Machining (ECDM), Ultrasonic Assisted Electric Discharge Machining (UAEDM), Electrochemical
Discharge Grinding (EDG), Powder Assisted Electric Discharge Machining (PAEDM).

MODULE 5:
Jigs and Fixtures: Importance of jigs and fixtures; the difference between jigs and fixtures; types
of jigs and fixtures; essential features of jigs and fixtures, Materials used. Factors to be considered
for the design of Jigs and Fixtures; Jigs: Template, Plate, Channel, Diameter, Leaf, Rung, Box,
Fixtures: Turning, Milling, Broaching, Grinding, Boring, Indexing, Tapping, Duplex, Welding, and
Assembly fixtures.
MACHINING SCIENCE AND JIGS & FIXTURES 21ME42

Module 1
Introduction to Machining Processes and Machine Tools
Machining is a manufacturing process that involves the removal of material from a workpiece to
create a desired shape and size. Machining can be performed using a variety of tools and
processes, each with its own advantages and limitations.

There are several types of machining processes, including:

1. Turning: Turning is a process that involves rotating a workpiece on a lathe and using a
cutting tool to remove material from the outer diameter of the workpiece. Turning is used
to create cylindrical shapes, such as shafts and tubes.

2. Milling: Milling involves using a rotating cutting tool to remove material from the
surface of a workpiece. Milling can be used to create a wide range of shapes and features,
including slots, pockets, and contours.

3. Drilling: Drilling is a process that involves creating holes in a workpiece using a rotating
cutting tool. Drilling can be performed using a drill press or a CNC machine.

4. Grinding: Grinding involves using a rotating abrasive wheel to remove material from the
surface of a workpiece. Grinding is used to create smooth surfaces and tight tolerances.

5. Broaching: Broaching is a process that involves using a specialized cutting tool to create
a specific shape or feature in a workpiece. Broaching is commonly used to create
keyways and splines.

6. Electrical Discharge Machining (EDM): EDM involves using a series of electrical

discharges to remove material from a workpiece. EDM is commonly used to create
complex shapes and features in hard materials.

Machining processes can be performed manually, using hand-held tools, or using CNC
machines, which are computer-controlled machines that can perform a wide range of machining
operations with high precision and accuracy. The choice of machining process depends on
factors such as the desired shape and size of the workpiece, the material being machined, and the
required tolerances and surface finish.

Machining processes can be classified based on several criteria, including the type of tool used,
the type of motion involved, the type of energy used, and the type of workpiece being machined.
Here are some common classifications of machining processes:

1. Based on the type of tool used:

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 Cutting processes: involve the use of cutting tools, such as drills, saws, milling cutters,
and grinding wheels, to remove material from the workpiece.

 Non-cutting processes: involve the use of non-cutting tools, such as lasers, EDM, and
water jets, to remove material from the workpiece.

2. Based on the type of motion involved:

 Rotational machining: involve rotating the workpiece and/or tool, such as turning and
milling.

 Reciprocating machining: involve linear motion of the tool or workpiece, such as drilling
and sawing.

 Oscillatory machining: involve back-and-forth motion of the tool or workpiece, such as

honing and lapping.

3. Based on the type of energy used:

 Mechanical machining: involve the use of mechanical energy to remove material, such as
cutting, grinding, and milling.

 Thermal machining: involve the use of heat to remove material, such as laser cutting and
oxy-fuel cutting.

 Electrical machining: involve the use of electrical energy to remove material, such as
EDM and electrochemical machining.

4. Based on the type of workpiece being machined:

 Conventional machining: involve the machining of metals and other conventional

materials.

 Advanced machining: involve the machining of advanced materials, such as composites,

ceramics, and alloys.

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Construction of lathe machine

A lathe machine is a tool that is used to shape materials, such as metal or wood, by rotating them
against a cutting tool. The construction of a lathe machine typically consists of the following
components:

1. Bed: The bed is the base of the machine and provides a stable platform for the other
components. It is typically made of cast iron and is designed to resist deflection and
vibration.

2. Headstock: The headstock is located at one end of the bed and contains the motor,
spindle, and other components that drive the workpiece. It is responsible for rotating the
workpiece at a constant speed.

3. Tailstock: The tailstock is located at the other end of the bed and supports the other end
of the workpiece. It can be moved along the bed to accommodate different lengths of
workpieces and can be locked in place to hold the workpiece securely.

4. Carriage: The carriage is the component that holds the cutting tool and moves along the
bed to make cuts in the workpiece. It consists of a saddle that slides along the bed and a
cross slide that moves perpendicular to the bed.

5. Tool post: The tool post is located on the carriage and holds the cutting tool. It can be
adjusted to change the height and angle of the cutting tool.

6. Chuck: The chuck is a device that is attached to the spindle of the headstock and holds
the workpiece securely in place. It can be opened and closed to grip or release the
workpiece.

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7. Apron: The apron is located on the front of the carriage and contains the controls for
operating the machine, such as the feed and speed controls.

Lathe operations refer to the processes performed using a lathe machine to shape, cut, drill or
turn a workpiece. Lathe machines are commonly used in metalworking and woodworking
industries for producing cylindrical parts or components with high precision.

Here are some of the common lathe operations:

1. Facing: This is the process of cutting the end of the workpiece to create a flat surface.
The cutting tool is positioned perpendicular to the workpiece axis and moved across the
end surface to remove material

2. Turning: This involves rotating the workpiece against a cutting tool to remove excess
material and create a cylindrical shape. The cutting tool is mounted on a tool post, which
can be adjusted to achieve different cutting depths and angles.

3. Taper turning: This involves cutting a tapered shape on the workpiece. The cutting tool is
gradually moved inwards or outwards from the end of the workpiece to create the taper.

4. Boring: This is the process of enlarging an existing hole in the workpiece. A boring tool
is inserted into the hole and rotated to remove material and enlarge the hole.

5. Drilling: In this operation, a drill bit is used to create a hole in the workpiece. The drill bit
is held in a chuck and rotated against the workpiece to create the hole.

6. Threading: This involves cutting a screw thread on the workpiece. A special cutting tool
called a threading tool is used to create the thread.

7. Knurling: This is the process of creating a pattern of small ridges on the surface of the
workpiece. A knurling tool is pressed against the rotating workpiece to create the pattern.

Construction of Shaping Machine

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A shaping machine, also known as a shaper, is a machine tool used for shaping and cutting
metals. The construction of a shaping machine typically consists of the following components:

1. Base: The base is the foundation of the machine and provides a sturdy support for the
other components.

2. Column: The column is a vertical pillar that supports the other components and provides
a guide for the tool head.

3. Tool head: The tool head is mounted on the column and moves vertically to adjust the
depth of cut. It contains the cutting tool, which can be adjusted to control the depth and
angle of the cut.

4. Ram: The ram is a horizontal component that moves back and forth to control the length
of the cut. It is mounted on the tool head and can be adjusted to change the cutting speed
and direction.

5. Table: The table is a flat surface that supports the workpiece and moves horizontally to
control the width of the cut. It can be adjusted to accommodate different sizes of
workpieces and can be locked in place to hold the workpiece securely.

6. Feed mechanism: The feed mechanism is responsible for moving the workpiece and the
cutting tool during the cutting process. It can be adjusted to control the rate of feed and
the depth of cut.

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7. Drive mechanism: The drive mechanism provides the power to rotate the cutting tool and
move the workpiece. It consists of a motor, belts, and gears that work together to provide
the necessary speed and torque

Shaper Machine Operations

The following are the shaper machine operations:

1. Machining horizontal surface

2. Vertical surfaces
3. Angular surfaces
4. Irregular surfaces
5. Cutting slots, grooves, and keyways
6. Machining splines or cutting gears.

1. Machining Horizontal Surfaces

It is the most common shaper machine operations. In this, the work is fed in a horizontal
direction under the reciprocating tool and the surface produced is horizontal and flat.The
work is either held in a vice or clamped directly on the machine table, depending upon its
size. The tool is held in a proper tool holder. It is set at a proper inclination and at the correct
height above the work, as described later in this article. The depth of cut adjusted and the
machine get starts. Crossfeed to the table is given initially by hand until the cut starts. After
that power feed can be employed. After the cut is finished, the machine is stopped and the
work inspected. If more material is to be removed, the procedure is repeated until the desired
surface is obtained.

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2. Machining Vertical Surfaces

A vertical cut is made while machining the end of a workpiece, squaring up a block or
cutting a shoulder. The work is attached in the vice or directly on the table and the
surface to be machined is carefully aligned with the axis of the ram. A side cutting tool is
set on the tool post and the position and length of stroke are adjusted. The vertical slide is
set accurately at zero position. This is necessary to enable the tool to move upwards and
away from the work during the return stroke. This prevents the side of the tool from
dragging on the planed vertical surface during the return stroke. The down-feed is given
by rotating the down feed screw by hand. The feed is about 0.25mm given at the end of
each return stroke. Both roughing and finishing cuts are done to complete the job.

3. Machining Angular Surface

In this shaper machine operation, an angular cut is done at any angle other than a right
angle to the horizontal or to the vertical plane. The work is set on the table and the
vertical slide of the tooth head is swivelled to the required angle either towards the left or
towards right from the vertical position. The apron is then further swivelled away from
the work so that the tool will clear the work during the return stroke. The down feed is
given by rotating the down feed screw. The angular surface can also be machined in a
universal shaper or by using a universal vice without swivelling the tool head.

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4. Cutting Slots and Keyways

With suitable tools, a shaper can very conveniently machine slots or grooves on work or
cut external keyways on shafts and internal keyways on pulleys or gears. For cutting slots
or keyways on shafts and internal keyways on pulleys or gears. For cutting keyways or
slots a square nose tool similar to a parting tool is used. External keyways are made on a
shaft by first drilling a hole at the blind end of the keyway. The diameter of the hole
should be 0.5 to 0.8mm oversize than the width of the keyway and the depth should be
about 1.5mm larger than the depth of the keyway. This is important to leave clearance on
the tool at the end of the stroke. The length and position of stroke are carefully adjusted
so that the stroke will terminate exactly at the clearance hole. The speed is reduced while
cutting keyways

Construction of milling machine

A milling machine is a machine tool that uses rotating cutters to remove material from a
workpiece to create a desired shape. The construction of a milling machine typically consists of
the following components:

1. Base: The base is the foundation of the machine and provides a sturdy support for the
other components.

2. Column: The column is a vertical pillar that supports the other components and provides
a guide for the spindle.

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3. Knee: The knee is a horizontal component that moves up and down along the column to
adjust the height of the worktable.

4. Worktable: The worktable is a flat surface that supports the workpiece and moves
horizontally to control the movement of the workpiece during the milling process.

5. Spindle: The spindle is the rotating component that holds the cutting tool and moves
vertically and horizontally to create the desired shape. It is mounted on the column and
can be adjusted to control the depth and direction of the cut.

6. Arbor: The arbor is a component that connects the cutting tool to the spindle and provides
a way to change the cutting tool quickly and easily.

7. Motor: The motor provides the power to rotate the spindle and move the worktable and
cutting tool. It can be adjusted to control the speed and torque of the machine.

8. Control panel: The control panel contains the controls for operating the machine, such as
the speed and feed rate controls.

Milling Machine Operations

1. Plain Milling

 The plain milling is the most common types of milling machine operations.
• Plain milling is performed to produce a plain, flat, horizontal surface parallel to
the axis of rotation of a plain milling cutter.
• The operation is also known as slab milling.

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• To perform the operation, the work and the cutter are secured properly on the
machine.
• The depth of cut is set by rotating the vertical feed screw of the table.
 And the machine is started after selecting the right speed and feed

2. Face milling
 The face milling is the simplest milling machine operations.
 This operation is performed by a face milling cutter rotated about an axis perpendicular to
the work surface.
 The operation is carried in plain milling, and the cutter is mounted on a stub arbor to
design a flat surface.
 The depth of cut is adjusted by rotating the crossfeed screw of the table

3. Slot milling:
The process of producing keyways grooves and slots of varying shapes and sizes is
known as slotting. The side milling cutter is mounted on to the arbor of a horizontal
milling machine when slotting had to be done on Horizontal milling machine. T–Slots
and dovetail slots are carried out on a veridical milling machine

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4. Saw Milling

 Saw-milling is the operation of producing narrow slots or grooves on a workpiece by

using a saw-milling cutter.
 The saw-milling also performed for complete parting-off operation.
 The cutter and the workpiece are set in a manner so that the cutter is directly
placed over one of the T-slots of the table.

5. Form Milling

 The form milling is the operation of producing the irregular contour by using form cutters.

 The irregular shape may be convex, concave, or of any other shape. After machining, the

formed surface is inspected by a template gauge.

 Cutting rate for form milling is 20% to 30% less than that of the plain milling.

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6. Gear Cutting
 The gear cutting operation is performed in a milling machine by using a form-
relieved cutter. The cutter may be a cylindrical type or end mill type.
 The cutter profile fits exactly with the tooth space of the gear.
 Equally spaced gear teeth are cut on a gear blank by holding the work on a
universal diving head and then indexing it.

Construction of grinding machine

A grinding machine is a machine tool that uses abrasive wheels to remove material from a
workpiece to create a desired surface finish. The construction of a grinding machine typically
consists of the following components:

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1. Base: The base is the foundation of the machine and provides a sturdy support for the
other components.

2. Column: The column is a vertical pillar that supports the other components and provides
a guide for the wheel head.

3. Wheel head: The wheel head is mounted on the column and moves vertically and
horizontally to adjust the position of the grinding wheel. It contains the grinding wheel,
which rotates at a high speed to remove material from the workpiece.

4. Worktable: The worktable is a flat surface that supports the workpiece and can be
adjusted to control the movement of the workpiece during the grinding process.

5. Grinding wheel: The grinding wheel is the abrasive wheel that removes material from the
workpiece. It can be made of various materials, including aluminum oxide, silicon
carbide, and diamond.

6. Wheel dresser: The wheel dresser is a tool that is used to shape the grinding wheel to the
desired profile. It is mounted on the machine and can be adjusted to control the shape and
angle of the wheel.

7. Motor: The motor provides the power to rotate the grinding wheel and move the
worktable and wheel head. It can be adjusted to control the speed and torque of the
machine.

8. Coolant system: The coolant system is used to cool the grinding wheel and workpiece
during the grinding process. It can be adjusted to control the flow and temperature of the
coolant.

Construction of drilling machine

A drilling machine is a machine tool used to create holes in materials. The construction of a
drilling machine typically consists of the following components:

1. Base: The base is the foundation of the machine and provides a sturdy support for the
other components.

2. Column: The column is a vertical pillar that supports the other components and provides
a guide for the drill head.

3. Drill head: The drill head is mounted on the column and contains the drilling tool, which
rotates to create the hole in the workpiece. It can be adjusted to control the depth and
angle of the hole.

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4. Spindle: The spindle is the rotating component that holds the drilling tool and moves
vertically to create the hole in the workpiece. It is mounted on the drill head and can be
adjusted to control the speed and torque of the machine.

5. Worktable: The worktable is a flat surface that supports the workpiece and can be
adjusted to control the movement of the workpiece during the drilling process.

6. Feed mechanism: The feed mechanism is responsible for moving the drilling tool and the
workpiece during the drilling process. It can be adjusted to control the rate of feed and
the depth of the hole.

7. Motor: The motor provides the power to rotate the drilling tool and move the worktable
and drill head. It can be adjusted to control the speed and torque of the machine.

Drilling Machine Operations

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Following are the different types of operations performed on the drilling machine:

1. Drillingoperation
2. Reamingoperation
3. Boringoperation
4. Counterboringoperation
5. Countersinkingoperation
6. Spot facingoperation
7. Tappingoperation
8. Lappingoperation
9. Grindingoperation
10. Trepanningoperation
1. Drilling

Drilling is the operation of producing a cylindrical hole by removing metal from the rotating
edge of a cutting tool called the drill.

The drilling is one of the simplest methods of producing a hole. Before drilling the centre of
the hole is located on the workpiece by drawing two lines at right angles to each other and
then a centre punch is used to produce an indentation at the centre.

The drill point is pressed at this centre point to produce the required hole. Drilling does not
produce an accurate hole in a workpiece and the hole location is not perfect.

The internal surface of the hole so generated by drilling becomes rough and the hole is always
slightly oversize than the drill used due to the vibration of the spindle and the drill. A 12mm
drill may produce a hole as much as 0-125mm oversize and a 22mm drill may produce one as
much as 0-5mm oversize.

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2. Reaming
Reaming is an accurate way of sizing and finishing a hole which has been previously drilled.
In order to finish a hole and to bring it to the accurate size, the hole is drilled slightly
undersize.

The speed of the spindle is made half that of drilling and automatic feed may be employed. The

tool used for reaming is known as reamer which has multiple cutting edges.

Reamer cannot originate a hole. It simply follows the path which has been previously drilled
and removes a very small amount of metal. For this reason, a reamer cannot correct a hole
location. The material removed by this process is around 0-375mm and for accurate work, this
should not exceed 0-125mm.

3. Boring

Boring is performed in a drilling machine for reasons stated below:

 To enlarge a hole by means of an adjustable cutting tool with only one cutting edge. This is
necessary where the suitable sized drill is not available or where the hole diameter is so large
that it cannot be ordinarilydrilled.
 Used to finish a hole accurately and to bring it to the requiredsize.

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 To machine the internal surface of a hole already produced incasting.

 Used to correct out of roundness of thehole.
 To correct the location of the hole as the boring tool follows an independent path with
respect to thehole.

The cutter is held in a boring bar which has a tapered shank to fit into the spindle socket. For
perfect finishing a hole, the job is drilled slightly undersize. In precision machines, the
accuracy is as high as
+0.00125mm. It is a slow process than reaming and requires several passes of the toll.

4. Counterboring
Counterboring is the operation of enlarging the end of a hole cylindrically. The enlarged hole
forms a square shoulder with the original hole. This is necessary in some cases to
accommodate the heads of bolts, studs and pins.

Atoolusedforcounterboringiscalledacounterbore.Thecounterboresaremadewithastraightor
tapered shank to fit in the drill spindle. The cutting edges may have straight or spiralteeth.

The tool is guided by a pilot which extends beyond the end of the cutting edges. The pilot
fits into the small-diameter hole running clearance and maintains the alignment of the tool.

These pilots may be interchanged for enlarging different sizes of holes. Counterboring can
give an accuracy of about +0.005mm. The cutting speed for counterboring is 25% less than
that of drilling operations.
5. Countersinking
Countersinking is the operation of making a cone-shaped enlargement of the end of a
hole to provide a recess for a flat head screw or countersunk rivet fitted into the hole.

The tool used for countersinking is called a countersink. Standard countersinks have 60, 82 or
90 inclined angle and the cutting edges of the tool are formed at the conical surface. The

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cutting speed in countersinking is 25% less than that of drilling.

6. Spotfacing
Spot facing is the operation of smoothing and squaring the surface around a hole for the seat
for a nut or the head of a screw. A counterbore or a special spot facing tool may be
employed for this purpose.

7. Tapping
It is the operation of cutting internal threads by means of a cutting tool called a tap.
Tapping in a drilling machine may be performed by hand or by machine.

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A tap may be considered as a bolt with accurate threads cut on it. The threads act as cutting
edges which are hardened and ground. When the tap is screwed into the hole it removes metal
and cuts internal threads which will fit into external threads of the same size.

8. Lapping

Lapping is the operation of sizing and finishing a small diameter hole already hardened by
removing a very small amount of material by using a lap. There are many kinds of lapping
tools.

The copper head laps are commonly used. The lap fits in the hole and is moved up and down
while it revolves.

9. Grinding

Grinding operation may be performed in a drilling machine to finish a hardened hole. The
grinding wheel is made to revolve with the spindle and is fed up and down.

A suitable grinding wheel may be selected for surface grinding operation. Grinding can also be
done correctly out of roundness of the hole. The accuracy in grinding operation is quite high
about+0.0025mm.

10.Trepanning

Trepanning is the operation of producing a hole by removing metal along the

circumference of a hollow cutting tool.
This operation is performed for producing large holes. Fewer chips are removed and much
of the material is saved while the hole is produced.

The tool may be operated at higher speeds as the vibration in diameter of the tool is limited
by the narrow cutting edge. The tool resembles a hollow tube having cutting edges at one
end and a solid shank at the other to fit into the drill spindle. This is one of the efficient
methods of producing a hole.

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Introduction to CNC machines

CNC stands for Computer Numerical Control, which is a technology used to automate the
control of machine tools, such as lathes, mills, routers, and grinders. CNC machines use a
computer program to control the movements of the machine tools, allowing for precise and
complex cuts and shapes to be created with ease.

CNC technology has revolutionized the manufacturing industry, as it allows for higher levels of
precision, accuracy, and repeatability than manual machining. CNC machines can produce parts
with consistent quality, reduce waste and errors, and increase efficiency and productivity.

The CNC technology works by using a computer program that contains a set of instructions,
called G-code, that directs the machine tool's movements. The program is loaded into the CNC
machine's computer, which controls the movements of the machine based on the G-code
instructions. The machine's cutting tool moves along the X, Y, and Z axes, following the
programmed path to create the desired shape or cut.

CNC technology has been widely adopted in industries such as aerospace, automotive, medical,
and manufacturing. CNC machines are used to produce a wide range of products, from simple
components to complex parts used in advanced machinery. With the continuous development of
computer technology and automation, the applications of CNC technology are constantly
expanding, and it is becoming increasingly prevalent in various fields.

CNC lathe machine

A CNC lathe machine is a computer-controlled machine tool that is used to produce precision
parts through a variety of cutting operations. CNC lathes are used in a wide range of
manufacturing industries, from aerospace to automotive to medical, due to their ability to
produce high-quality and consistent parts with a high level of accuracy.

The construction of a CNC lathe machine is similar to a conventional lathe, with the addition of a
computer-controlled system that allows for more precise and complex cuts. The key components
of a CNC lathe machine include:

1. Bed: The bed is the base of the machine and provides support for the other components.
It is typically made of cast iron and provides a rigid structure for the machine.

2. Headstock: The headstock is mounted on the bed and contains the spindle that rotates the
workpiece. The spindle can be controlled by the CNC system to vary the speed and
direction of rotation.

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3. Tailstock: The tailstock supports the opposite end of the workpiece and can be adjusted to
hold the workpiece in place during machining operations.

4. Tool turret: The tool turret holds the cutting tools and can be rotated to select the
appropriate tool for the job. The tool turret is controlled by the CNC system, which
determines the appropriate tool for each cutting operation.

5. CNC controller: The CNC controller is the computer that controls the machine's
movements and cutting operations. It receives instructions from a computer program and
sends signals to the machine's motors to move the cutting tools and workpiece in the
desired direction.

6. Motors: The machine's motors provide the power to move the cutting tools and
workpiece. They are controlled by the CNC system to ensure precise and accurate
movement.

7. Coolant system: The coolant system is used to cool the cutting tools and workpiece
during machining operations to prevent overheating and damage to the parts.

CNC lathe machines offer a number of advantages over conventional lathes, including increased
precision, accuracy, and consistency, as well as the ability to produce complex shapes and
designs. CNC lathes are widely used in industries that require high-quality, precise parts, and
they have become an essential tool in modern manufacturing processes

CNC machines are used extensively in manufacturing industries for their ability to produce
highly precise and complex parts with a high level of accuracy. Some of the most common types
of CNC machines include:

1. CNC Lathe: A CNC lathe machine is used to produce cylindrical parts through a variety
of cutting operations. CNC lathes are widely used in industries such as automotive,
aerospace, and medical for their ability to produce high-quality and consistent parts.

2. CNC Milling Machine: A CNC milling machine is used to cut and shape solid materials
such as metal, plastic, and wood. CNC milling machines are widely used in industries
such as aerospace, automotive, and medical for their ability to produce highly precise and
complex parts.

3. CNC Drilling Machine: A CNC drilling machine is used to drill holes in materials such
as metal and plastic. CNC drilling machines are widely used in industries such as
aerospace, automotive, and construction for their ability to produce precise and accurate
holes.

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4. CNC Machine Center: A CNC machine center is a versatile machine tool that can
perform a variety of cutting operations such as milling, drilling, and tapping. CNC
machine centers are widely used in industries such as aerospace, automotive, and medical
for their ability to produce highly precise and complex parts

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