CNC Lathe Operating & Programming

CNC – Lathe OperatingCNC – Lathe Operating
& Programming& Programming
Prepared by
Virender Singh Bhati
Akash Shukla
Guidance by Mr. Dharmendra Rajput
HOD – Tool Room Department
NSIC Rajkot
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Introduction CNC Technology
CNC-Computer Numerical Control
CNC is a method of automatically operating a machine
by using letter, numbers and special characters.
Use of CNC Machine
For high accuracy
For lot production
For high production rate
For manufacturing critical shape which not possible on
conventional
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CNC Machine
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Shukla

Parts of CNC Lathe
Head Stock
Tailstock
Control Panel
Coolant Tank
Chuck
Turret
Chuck Pedal

JAW
It is use
for Hold
work
piece
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The turret
holds and
moves the
tools.
Tools are
bolted to
the turret
using a
variety of
specialized
holders,
depending
on the type
of tool.
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For Hold
Long Work
piece
During
Machining
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It is use for
Clamp(Loading) &
Decamp (Unloading) of
Work piece
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Principal of CNC Lathe
In cnc lathe machine tool in movement against
rotating work piece.
Tool in movement linear
Work piece is rotating
Work Piece – Cylinder
Tool – Single Point Cutting Tool

Work Piece Zero Position
The work piece zero point (W)
is specified by the
programmer and should
always be chosen according
to the dimensioning of the
drawing. For turning work it
lies mostly on the turning axis
and the right hand face.

Home Position / Ref. Position
The reference point (R) is
also called Home position.
At Home Position Machine
position is always Zero.
We can change our tool
automatically at Home
Position.

Machine Zero & Program Zero

Points and distances with the work space
 The machine zero point (M) is determined by the machine
manufacturer and cannot be changed. On turning machines
point is usually set on the spindle flange.
 The work piece zero point (W) is specified by the programmer
and should always be chosen according to the dimensioning
of the drawing. For turning work it lies mostly on the turning
axis and the right hand planar face.
 The reference point (R) is approached for initializing the path
measuring system, which means that at this point all axes are
set to zero. This is necessary since generally speaking the
machine zero point cannot be approached.

AXIS NOMENCLATURE
From work piece zero point
 Moving left (towards spindle) Z-ve
 Moving right (away from spindle)Z+ve
 Moving above spindle center line X+ve
 Moving below spindle center line X–ve

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Z axis - Length of Work Piece
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Raw Material Size:-Dia.32X70mm
Tools
1.Rough Turning Tool
2.Finish Turning Tool
CNC Lathe ToolsCNC Lathe Tools
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Boring bar SleeveBoring bar Sleeve
It is use for hold
boring bar sleeve
size is defend on
Boring bar Size
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Boring ToolBoring Tool
Tools
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Grooving ToolGrooving Tool
Tools
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Threading ToolThreading Tool
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I.D. Threading ToolI.D. Threading Tool
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Operation of CNC Lathe
Facing
Turning
Taper Turning
Drilling
Boring
Grooving
External Threading
Internal Threading

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Measuring Instrument
Steel Rule
The steel rule is a basic measuring tool. Steel rule is an accurate
measuring device. Steel rules come in many sizes and formats.
Basic 15cm,30cm,60cm & 100cm
Least Count 0.05mm
1mm – 1000 micron
1cm – 10 mm
1 Meter – 100 cm
1 inch – 25.4 mm
1 inch – 2.54 cm

Micrometer
A micrometer sometimes known as a micrometer screw
gauge A micrometer is a measuring instrument, used to
very fine measurements and available in metric and
imperial versions. It is used for thickness of plates,
Diameter of job. It is available in 0-25mm, 25-50mm, 50-
75mm, 75-100mm.
Least count - 0.01mm

Venire Caliper
A venire caliper is a measuring tool. It can be used for
measurements, outside distance (such as the length of
an object), inside distance such as the width of a groove
or the diameter of a large hole, and depth, such as the
depth of a hole or the height of a step.
Least count - 0.02mm

Digital Venire Caliper
Modern venire calipers are digital – in the sense it has an
LCD display on which the reading appears – there is no
possibility of human error in reading the scale

Bore gauge
 A bore gauge is a convenient term for the
measuring or transfer tools that are used in
the process of accurately measuring holes. A
dial bore gauge is a special tool, calibrated
in .001 inch (.0025 centimeter) or .0001 inch
(.00025 centimeter), which is used to
accurately measure the inside diameter of a
hole, cylinder or pipe. In conjunction with a
micrometer, a bore gauge will give you the
exact reading of a bore size. A typical bore
gauge is comprised of a shaft with a dial
indicator at the top and a measuring sled at
the base. The measuring sled consists of
three guides and an actuating plunger. Dial
bore gauges give you quick and accurate
readings on the size, less than perfect
roundness or wear. 60Prepared by V.S.Bhati & Akash Shukla

Bore gauge
 Dial indicator (distance amplifying instrument)
A measuring instrument with a contact point attached to a spindle and gears
that moves a pointer on the dial. Dial indicators have graduations that are
available for reading different measurement values.
 How to use a dial bore gauge:
1. Zero the gauge. This is accomplished by measuring across the gauge with
an outside micrometer set to the precise bore size. When the zero aligns
with the needle you're ready.
2. Insert the gauge into the bore to the depth you need. Rock it back and forth
until it's properly inserted in the pipe.
3. Look at the reading. This is the lowest reading, which is taken when the
gauge is square on the bore, and the indicator needle reverses its direction.
It can be either more or less than the zero mark, and will indicate an oversize
or undersize bore

Bore gauge
 Type Of Dial Gauges :
• Plunger Type Dial Gauges
• Lever Type Dial Gauges
 Plunger Type Dial Gauges:-
This is a type of sturdy dial gauge and
is provided with tolerance pointers.
Moreover, our gauges have smooth
and strong metal bezel. Our gauges
are also fitted with swiss brass bush
bearings. The other features of
these gauges are mentioned below:

List of Address Codes

LIST OF G CODES

List of Canned Cycle

G00 (Rapid Traverse)
 The G00 code executes a non cutting movement, at a rapid movement
 A G00 command is written in the following format:
G00 X _ _ Z _ _ ;
where,
 X - X axis co-ordinate values (Diameter of Work piece)
 Z - Z axis co-ordinate values (Length of Work piece)

G01 (Linear Interpolation)
 The G01 code executes a cutting movement following a straight line, at a set federate
G01 X _ _ Z _ _ F _ _ ;
where,
 X - X axis co-ordinate values (Diameter of Work piece)
 Z - Z axis co-ordinate values (Length of Work piece)
 F – Feed rate
Note:
Programmed in absolute values as X and Z,
or
Incremental values as U and W are the X,
and Z axis co-ordinate values

G02 / G03 (Circular Interpolation)
 The G02 code use for cutting a clockwise circular path, at a set federate in a radius
 The G03 code use for cutting anticlockwise circular path, at a set federate in a radius
G02 X _ _ Z _ _ R _ _ F _ _;
G03 X _ _ Z _ _ R _ _ F _ _;
 Absolute position (X, Z), the value is the dimension of the end point of the arc
Incremental position (U, W), the co-ordinate of the end point is the distance the tool
moves from the start position of the arc

LIST OF M-CODES

M Codes
M00 (Program Stop):
 When the machine controller reads the code M00 within a block, it halts the program
 The [CYCLE START] key must be pressed to allow the program to continue
M01 (Optional Stop):
 The M01 code performs the same function as the M00 code (program stop), except
the machine controller only recognizes the signal to halt the program if the optional
[STOP] input key is activated
M03 (Spindle Rotation in Clock Wise ):
 Clockwise rotation of the spindle
 The spindle Rotation command is input stating the program
M04 (Spindle rotation in counter clock wise ):
 Counter clockwise rotation of the spindle
 The spindle Rotation command is input stating the program

M Codes
M05 (Spindle Stop):
 The M05 code, to stop the spindle rotating, is activated at the end of the block in which
it is programmed, i.e. , after any axis movement
M06 (Automatic Tool Change):
 This code activates the machine turret and is followed by the code T_ _ _ _,
instructing it to move to the stated tool number
 For example, M06 T0303 ;
 This command is read change automatically from the current tool number to tool
number 3
M08 (Coolant On):
 This code switches the coolant pump on
M09 (Coolant Off):
 This code switches the coolant pump off

M Codes
M19 (Spindle Orientation)
 This Code Lock the Machine spindle
 It is use when we change jaw of Machine
M30 (Program Stop and Reset):
 This code stops the running program
 Control is then reset back to the beginning of this program
 The program will be reset back to the stated block number
 The M30 code also acts as an M05 and M09

G20 / G21(Inch/Metric Data Input)
 The machine controller can be programmed in either Imperial (inch) unit input (G20) or
Metric (millimeter) unit input (G21). The standard format for a CNC part program is to
write the G20 or G21 code in the Starting block of the program

For I.D. Finishing
Operation We Use G41

For O.D. Finishing
Operation We Use G42

Tool Compensation Number
1. Back Boring Tool
2. Boring Tool
3. Right Hand Turning Tool
4. Left Hand Turning Tool
5. Back Facing Tool
6. ID Grooving Tool
7. Facing Tool
8. OD Grooving Tool
9. For Centre of Work Piece 78Prepared by V.S.Bhati & Akash Shukla

G50 (Max. Spindle Speed)
G50 S_ _ _ _ specifies the maximum spindle speed for constant
surface speed control, measured in R.P.M.
Format to specify the address
G50 S_ _; (specified Maximum Spindle Speed)

G96 (Constant Surface Speed Control)
 If surface speed is set after the address S __ , the spindle speed is calculated so that
the surface speed is always the specified value in relation to the tool positioned
 A G96 command for surface speed control is written in the following format:
G96 S __ ;
where,
S __ is the spindle speed (mm/min or inch/min)

G97 (Constant Surface Speed Control Cancel)
 The G97 command allows a spindle for constant surface speed control cancel speed
written in the units, revs per minute
 A G97 command for spindle speed control is written in the following format:
G97 S __ ;
where,
S __ is the spindle speed, written in the format revs per minute

G98 (Feed per minute)
 The G98 command allows a federate written in the units, millimeters per minute or
inches per minute, to be entered into the machine controller
 G98 commend input in starting the program

G99 (Per Revolution Feed)
 The G99 command allows a federate written in the units, millimeters per revolution or
inches per revolution, to be entered into the machine controller
 G99 command input at starting the program

How to Calculate Spindle Speed
Vc = ╥DN/1000
N = Vc x 1000/ ╥ D
Vc = Cutting Speed
D = Diameter of Work piece
N = Spindle Speed
╥ = 3.14

How to Calculate Spindle Speed
Vc = ╥DN/1000
N = Vc x 1000/ ╥ D
Vc = Cutting Speed
D = Diameter of Work piece
N = Spindle Speed
╥ = 3.14
For M.S. Dia. 30 mm
O65646;
G99 G21;
G28 U0.0 W0.0;
T0101;
G96 S250 M04;
G50 S2500;
G96 :- Minimum Spindle Speed
G50 :- Maximum Spindle Speed
N=250x1000/3.14x30
2500 RPM

Feed Rate
Rough Turning/Boring - (0.18-0.25)
Finish Turning/Boring – (0.12-0.18)
Grooving/Drilling - (0.1)

Example For Coordinate
Raw Material Size:-Dia.32X70

Example For Coordinate

Example

Example
N01 X17.5 Z0.0
N02 X17.5 Z-20.0
N03 X22.5 Z-20.0
N04 X22.5 Z-30.0
N05 X32.0 Z-30.0

Exercise

Exercise
N01 X20.0 Z0.0
N02 X20.0 Z-32.0
N03 X30.0 Z-32.0
N04 X30.0 Z-40.0

Program Format
O1000; Program No.
G21 G99; Program parameter
G28 U0.0 W0.0; Home Position
T0101; Tool No.
M03 S800; Spindle Rotation
M08; Coolant ON
G00 X35.0 Z5.0; Near to Work Piece
G00 X30.0 Z1.0; Touch to Work Piece
;Canned Cycle
;Work Piece Coordinate
G00X50.0; Distance From
G00Z10.0; Work piece
M05; Spindle Stop
M09; Coolant OFF
G28U0.0W0.0; Home Position
M30; Program End

O2001;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G01 X-2.0 F0.2;
G00 W1.0;
G00 X32.0;
G00 Z0.5;
G01 X-2.0 F0.2;
G00 W1.0;
G00 X32.0;
G00 Z0.0;
G01 X-2.0 F0.2;
G00 W1.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
Facing Part Programming
Raw Material Size:-Dia.32
Face stock 1 mm

Facing Part Programming
Raw Material Size:-Dia.32
Face stock 1 mm

Turning
Work piece
Tool

Exercise
O2002;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G00 X31.0;
G01 Z-40.0 F0.2;
G00 U1.0;
G00 Z1.0;
;
G00 X30.0
G01 Z-40.0 F0.2;
G00 U1.0;
G00 Z1.0;
;
G00 X29.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X28.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X27.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X26.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X25.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X24.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
G00 X23.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X22.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X21.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
;
G00 X20.0 ;
G01 Z-32.0 F0.2 ;
G00 U1.0;
G00 Z1.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30 98Prepared by V.S.Bhati & Akash Shukla

G71 (Stock Removal in X Axis)
 The G71 code commands a multiple repetitive cycle, sometimes referred to as a
canned cycle
 This G71 cycles are used within a CNC program to simplify programming, since only
the dimensions describing the required component profile are required. The CNC
control will then generate the roughing cuts needed to make this component profile,
from within its own memory.
Format:
G71 U_ _R_ _
G71 P_ _Q_ _U_ _W_ _F_ _
where,
U is the depth of cut in the X axis (Radius value)
R is the escaping amount (Retract)
P is the start block number finished shape.
Q is the last block number finished shape.
U is the finishing allowance in the X axis (Diameter value).
W is the finishing allowance in the Z axis.
F is the federate for Roughing

Tool Path Example

Turning Exercise 01

Turning Exercise 01
Raw Material Size:-Dia.32x70

Raw Material Size:-Dia.32X70O2000;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q04 U0.0 W0.0 F0.2 ;
N01 G01 X20.0 Z0.0;
N02 G01 X20.0 Z-32.0;
N03 G01 X30.0 Z-32.0;
N04 G01 X30 Z-40.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
%
Turning Exercise 01

Turning Exercise No. 2
Raw Material Dia. 32x70 mm

Raw Material Size:-Dia.32X70mmO2000;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q06 U0.0 W0.0 F0.2 ;
N01 G01 X10.0 Z0.0;
N02 G01 X10.0 Z-10.0;
N03 G01 X20.0 Z-10.0;
N04 G01 X20.0 Z-30.0;
N05 G01 X30.0 Z-30.0;
N06 G01 X30.0 Z-60.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
%
Turning Exercise No. 2

Exercise - 01
Turning Exercise 03

Turning Exercise 03
O2000;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X25.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q05 U0.0 W0.0 F0.2 ;
N01 G01 X17.50 Z0.0;
N02 G01 X17.5 Z-20.0;
N03 G01 X22.5 Z-20.0;
N04 G01 X22.5 Z-30.0;
N05 G01 X25.0 Z-30.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
%

Turning With Angle Exercise 01
O2001;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X60.0 Z10.0;
G00 X52.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q06 U0.0 W0.0 F0.2 ;
N01 G01 X32.88 Z0.0;
N02 G01 X39.0 Z-35.0 (A175);
N03 G01 X39 Z-40.0;
N04 G01 X44.0 Z-40.0;
N05 G01 X44.0 Z-60.0;
N06 G01 X52.0 ;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
%

Turning with Chamfer Exercise 01O2002;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q10 U0.0 W0.0 F0.2 ;
N01 G01 X12.0.0 Z0.0;
N02 G01 X15.0 Z-1.5;
N03 G01X15.0 Z-15.0;
N04 G01 X22.0 Z-15.0;
N05 G01 X25.0 Z-16.5;
N06 G01 X25.0 Z-30.0;
N07 G01 X27.0 Z-30.0;
N08 G01 X30.0 Z-31.5;
N09 G01 X30.0 Z-50.0;
N10 G01 X32.0;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30; 111Prepared by V.S.Bhati & Akash Shukla

Exercise Raw Material Size:-Dia.50X70

Turning with Chamfer Exercise 02
O2003;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X60.0 Z10.0;
G00 X52.0 Z1.0;
G71 U0.5 R1.0;
G71 P01 Q11 U0.0 W0.0 F0.2 ;
N01 G01 X18.0. Z0.0;
N02 G01 X20.0 Z-1.0;
N03 G01 X20.0 Z-12.0;
N04 G01 X28.0 Z-12.0;
N05 G01 X31.0 Z-13.5;
N06 G01 X31.0 Z-27.0;
N07 G01 X37.0 Z-27.0;
N08 G01 X41.0 Z-29.0;
N09 G01 X41.0 Z-37.0;
N10 G01 X49.0 Z-37.0;
N11 G01 X49.0 Z-45.0;
N12 G01 X52.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30; 113Prepared by V.S.Bhati & Akash Shukla

Turning with Radius Exercise 01
28

Exercise
O2003;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q06 U0.0 W0.0 F0.2 ;
N01 G01 X18.0. Z0.0;
N02 G01 X20.0 Z-4.0;
N03 G01 X20.0 Z-16.0;
N04 G03 X28.0 Z-20.0 R4;
N05 G01 X28.0 Z-30.0;
N06 G01 X32.0 Z-38.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30;
%
28

Turning with Radius Exercise 02

Example Raw Material Size:-Dia.30X70
O2003;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q07 U0.0 W0.0 F0.2 ;
N01 G01 X8.0. Z0.0;
N02 G03 X16.0 Z-4.0 R4;
N03 G01 X20.0 Z-12.0;
N04 G02 X20.0 Z-14.0 R2;
N05 G01 X20.0 Z-27.0;
N06 G03 X30.0 Z-32.0 R5;
N07 G01 X32.0 Z-40.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30;
% 117Prepared by V.S.Bhati & Akash Shukla

Facing

G72 (Stock Removal in Facing)
 The G72 code commands a multiple repetitive cycle. The G72 cycle is similar to the
G71 cycle except that the cut is applied in the Z axis
A G72 command is written in the following format
G72 W _ _R _ _
G72 P_ _Q _ _U _ _W _ _F _ _
where,
W is the depth of cut in the Z axis.
R is the Retract amount
P is the start block number finished shape.
Q is the last block number finished shape.
U is the finishing allowance in the X axis (Diameter value).
W is the finishing allowance in the Z axis.
F is the federate for Roughing

Tool Path Example

Raw Material:- Dia. 30X70
Facing Exercise 01

Example
O2002;
G40 G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X31.0 Z0.0;
G72 W0.5 R1.0;
G72 P01 Q03 U0.0 W0.0 F0.2 ;
N01 G01 X30.0 Z-8.0;
N02 G01 X-2.0 Z-8.0;
N03 G01 X-2.0 Z0.0;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30;
%
Raw Material:- Dia. 30X70mm

G73 (Pattern Repeating)
 The function of the G73 canned cycle is to permit the cutting of a programmed profile
repeatedly. It is mainly used for machined parts where the rough shape has already
been formed by either rough machining, forging or casting
G73 U _ _W _ _R _ _;
G73 P _ _Q _ _U _ _W _ _F _ _;
where,
U – X axis distance and direction of relief.
W – Z axis distance and direction of relief.
R – Number of cutting Divisions
P - is the start block number finished shape.
Q - is the last block number finished shape.
U - is the finishing allowance in the X axis (Diameter value).
W - is the finishing allowance in the Z axis.
F - is the federate

Example
O2001;
G40 G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X30.0 Z1.0;
G73 U5.0 W5.0 R5.0;
G73 P01 Q06 U0.0 W0.0 F0.2 ;
N01 G01 X32.88 Z0.0;
N02 G01 X39.0 Z-35.0;
N03 G01 X39 Z-40.0;
N04 G01 X44.0 Z-40.0;
N05 G01 X44.0 Z-60.0;
N06 G01 X50.0 ;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30

G70 (Finishing Cycle)
 After part profile rough cutting has been completed, using the G71, G72 or G73 codes,
the G70 code can be used to perform a finishing cut/pass
A G70 finishing pass command is written in the following format
G70 P _ _Q _ _F _ _
where,
P:- is the start block number of finished shape.
Q:- is the last block number of finished shape.
F:- Feed Rate

Turning with Finishing Exercise 01
N200;
G21 G99;
G28 U0.0 W0.0;
T0202;
M04 S1500;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G42;
G70 P01 Q06 F0.1;
G00 X60.0;
G40;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30
%
Raw Material:- Dia. 32X70
O2003;
N100;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q06 U0.3 W0.2 F0.2 ;
N01 G01 X18.0. Z0.0;
N02 G01 X20.0 Z-4.0;
N03 G01 X20.0 Z-16.0;
N04 G03 X28.0 Z-20.0 R4;
N05 G01 X28.0 Z-30.0;
N06 G01 X32.0 Z-38.0;
G00 X60.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;

G74 (End Face Peck Drilling Cycle)
The G74 code use for a peck drilling cycle
The drill runs centerline of the X axis and parallel to the Z axis, the
drill will make holes in the face end of the Work Piece
G74 command is written in the following format
G74 R _ _ ;
G74 Z _ _Q _ _ F _ _ ;
where,
R is the peck return amount
Z is the total depth of the hole
Q is the pecking depth in the Z axis measured in micron
F is the feed rate

Drilling Exercise 01
Drill Dia. – 10.00 mm
Raw Material Size:- Dia.52X70mm

Drilling Exercise 01 Drill Dia. – 10.00 mm
Raw Material Size:-Dia.52X70mmO2004; (Drill)
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S800;
M08;
G00 X0.0 Z10.0;
G00 Z1.0;
G74 R1.0;
G74 Z-20.0 Q1000 F0.1;
G00 Z15.0;
G00 X50.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%

Raw Material Size:-Dia.52X70 mmO2004; (Centre Drill)
G21 G40 G99;
N100;
G28 U0.0 W0.0;
T0101;
M04 S800;
M08;
G00 X0.0 Z10.0;
G00 Z1.0;
G74 R1.0;
G74 Z-3.0 Q1000 F0.1;
G00 Z15.0;
G00 X50.0;
M05;
M09;
G28 U0.0 W0.0;
N200; (Dia. 10 mm Drill)
G28 U0.0 W0.0;
T0202;
M04 S800;
M08;
G00 X0.0 Z10.0;
G00 Z1.0;
G74 R1.0;
G74 Z-20.0 Q1000 F0.1;
G00 Z15.0;
G00 X50.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%

Raw Material – Dia. 32X70mm

Drilling Exercise 02
O2003; (Centre Drill)
G21 G40 G99;
N100;
G28 U0.0 W0.0;
T0101;
M04 S800;
M08;
G00 X0.0 Z10.0;
G00 Z1.0;
G74 R1.0;
G74 Z-3.0 Q1000 F0.1;
G00 Z15.0;
G00 X50.0;
M05;
M09;
G28 U0.0 W0.0;
Drill Dia. – 12.00 mm
Raw Material – Dia. 32X70mm
N200; (Dia. 12 mm Drill)
G28 U0.0 W0.0;
T0202;
M04 S800;
M08;
G00 X0.0 Z10.0;
G00 Z1.0;
G74 R1.0;
G74 Z-24.0 Q1000 F0.1;
G00 Z15.0;
G00 X50.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%

G90 (Outer / Internal Dia. Cutting
Cycle)
 The command G90 performs a one pass cutting cycle, where the cut is applied in the
X axis. Also, by using the command R __ within the G90 block, tapers can be
generated
 If the one pass move needs to be repeated, only the values that change need to be
entered in the next block
A G90 command for written in the following format
G90 X __ Z __ F __
where,
X __ Work piece Diameter
Z __ Work Piece Length
F __ is the feed rate

Example - (Outer Cutting) 01
O2001;
G40 G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X32.0 Z1.0;
G90 X31.0 Z-40.0 F0.2;
X30.0;
G90 X29.0 Z-32.0 F0.2;
X28.0;
X27.0;
X26.0;
X25.0;
X24.0;
X23.0;
X22.0;
X21.0;
X20.0;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W.0;
M30;
%
RAW MATERIAL – Dia.32x70mm

Taper
 The sign of R depends on the cutting direction of path "P1" - in the above program, R
is entered as a minus value
 The G90 taper cut command can be used for both internal and external cutting
operations

Example 01 - ID Cutting (Boring)
RAW MATERIAL – OD Dia. 60x70mm
ID Dia. 35mm

Example - (Boring)
O2001;
G40 G21 G99;
G28 U0.0 W0.0;
T0101;
M03 S1200;
M08;
G00 X30.0 Z10.0;
G00 X33.0 Z1.0;
G90 X35.0 Z-35.0F0.2;
X36.0;
X37.0;
X38.0;
X39.0;
X40.0;
G00 Z10.0;
G00 X80.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%
RAW MATERIAL – OD Dia. 60x70mm
ID Dia. 35mm

Exercise - 01

G94 (End/Taper Face Turning Cycle)
 The G94 command performs a one pass face cutting cycle, where the cut is applied in
the Z axis
 If a repartition of the move is required, only the values that change need to be entered
into the next block
A G90 command for written in the following format
G94 X __ Z __ F __
where,
X __ Work piece Diameter
Z __ Work Piece Length
F __ is the feed rate

Facing by G94 Exercise 01
O2002;
G40 G21 G98;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X31.0 Z0.0;
G94 X-2.0 Z-1.0 F0.2;
Z-2.0;
Z-3.0;
Z-4.0;
Z-5.0;
Z-6.0;
Z-7.0;
Z-8.0;
G00 X40.0;
G00 X10.0;
M05;
M09;
G28 U0.0 W.0;
M30;
%

G75 (GROOVING CYCLE)
 The G75 command use for grooving in the X axis
A G75 command is written in the following format
G75 R _ _;
G75 X (U) _ _Z (W) _ _ P _ _Q _ _R _ _F _ _;
where,
the definitions of R, X (U) , Z (W) , P, Q, R and Fare the same as G74
where,
R is the peck return amount
X (U) is the diameter of the bore if step over is used (i.e., stepping along the X
axis to repeat the peck cycle)
Z (W) is the depth of the bore
P is the step over in the X axis measured in micron's (without sign)
Q is the pecking depth in the Z axis measured in micron's (without sign)
R (2) is the retract move at the base of the groove
F is the federate

Parting / Grooving

Insert Thickness - 3mm
Grooving Exercise 01
Raw Material – Dia. 32x70 mm

Raw Material – Dia. 32x70 mm
O0251;
G21 G99;
G28 U0.0 W0.0;
T0101;
M03 S500;
M08;
G00 X40.0 Z10.0;
G00 X35.0 Z1.0;
G00 Z-18.0;
G01 X28.0 F0.1;
G00 X35.0;
G00 Z-20.0;
G01 X28.0 F0.1;
G00 X35.0;
G00 X50.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30;

Example
O2002;
G40 G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X30.0 Z1.0;
G75 R2000
G75 X30. Z-20. P1.0 Q2.0 F0.2;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30;
%

Raw Material – Dia. 52x70mm

G76 (Multiple Thread Cutting Cycle)
 The G76 command contains, within two blocks, all the information required to
generate a standard thread form and pitch
A G76 uses one edge cutting to reduce the load on the tool tip
G76 P (A) / (B) / (C) _ _ _ _ _ _Q _ _R _ _;
G76 X _ _Z _ _P _ _Q _ _F _ _;
In First Block:-
G76 P (A) / (B) / (C) _ _ _ _ _ _Q _ _R _ _;
where,
 P (A) is the number of thread finishing passes (1 to 99)
 P (B) is the chamfer amount. This is the angle at which the tool leaves at the end of
the thread cutting cycle
 P (C) is the angle of the tool tip (80°, 60°, 55°, 30°, 29° and 0°)
 Note - (A), (B) and (C) are all specified at the same time by the address P,
 Ex, P030060 = number of cuts is 03, chamfer amount of 60 and tool angle of 60°
 Q is the minimum cutting depth (in microns)
 R is the finishing allowance 150Prepared by V.S.Bhati & Akash Shukla

G76 (Multiple Thread Cutting Cycle)
In Second Block:-
G76 X _ _Z _ _P _ _Q _ _F _ _;
where,
 X is the end position of the thread in the X axis (the minor diameter)
 Z is the end position of the thread in the Z axis
 P is the depth of the thread as a radius value (in microns)
 Q is the depth of the first pass as a radius value (in microns)
 F is the size of the thread Pitch
Minor Diameter
Calculation
d= Minor Diameter
D= Major Diameter
P=Thread Depth
d= D-2(P)
Thread Depth(P) = 0.6 x Pitch of Thread
Some Times
For Fine Thread 0.65
For Taper Thread:-
R=D-d/2
R – Taper
D – Major Dia.
d – Minor Dia.

Threading Exercise 01
O0033; (Threadding M32x1)
G28 U0.0 W0.0;
T0101;
G97 M04 S400;
M08;
G00X50.0Z10.0;
G00X34.0Z3.0;
G76 P010060 Q100 R0.05;
G76 X30.8 Z-14.0 P600 Q200 F1;
G00X50.0;
Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%
= 0.6 x 1
= 0.6
Minor Diameter Calculation
d= Minor Diameter
D= Major Diameter
P=Thread Depth
d= D-2(P)
= 32-2(0.6)
= 32-1.2
= 30.8 152Prepared by V.S.Bhati & Akash Shukla

Threading Exercise 02
O0033; Threadding M20x1.5
G28 U0.0 W0.0;
T0101;
G97 M04 S400;
M08;
G00 X30.0 Z10.0;
G00 X25.0 Z3.0;
G76 P010060 Q100 R0.05;
G76 X18.2 Z-40.0 P900 Q300 F1.5;
G00 X30.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W0.0;
M30;
%
M20 x 1.5
Length 40mm
= 0.6 x 1.5
= 0.9 mm
Minor Diameter Calculation
d= Minor Diameter
D= Major Diameter
P=Thread Depth
d = D - 2 (P)
= 20 – 2 (0.9)
= 20 - 1.8
= 18.2 mm

G92 (Thread Cutting Cycle)
 The G92 command performs a one pass threading cycle. Only the X (U) axis moves
need to be entered in subsequent blocks, after the original read-in of the G92
command
A G92 command for straight thread cutting is written in the following format
G92 X _ _Z _ _ F (Pitch) _ _R _ _;
where,
F Pitch of thread (federate)
Minor Diameter
Calculation
d= Minor Diameter
D= Major Diameter
P=Thread Depth
d= D-2(P)
Thread Depth(P) = 0.6 x Pitch of
Thread
Some Times
:- For Fine Thread = 0.65 x Pitch of
Thread
For Taper
Thread:-
R=D-d/2
R – Taper
D – Major Dia.
d – Minor Dia.

Exercise 01
O2002;
G21 G99;
G28 U0.0 W0.0;
T0101;
M04 S1200;
M08;
G00 X40.0 Z10.0;
G00 X30.0 Z1.0;
G71 U0.3 R1.0;
G71 P01 Q03 U0.0 W0.0 F0.2 ;
N01 G01 X 20.0 Z0.0;
N02 G01 X20.0 Z-25.0;
N03 G01 X30.0 Z-25..0;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28U0.0W0.0;
M30;
%

Threading G92 Exercise 01
O2021;
G40 G21 G98;
G28 U0.0 W0.0;
T0101;
G97 M04 S500;
M08;
G00 X30.0 Z10.0;
G00 X25.0 Z5.0;
G92 X20.0 Z-30.0 F1.5;
X19.80;
X19.60;
X19.40;
X19.20;
X19.00;
X18.80;
X18.60;
X18.40;
X18.20;
G00 X40.0;
G00 Z10.0;
M05;
M09;
G28 U0.0 W.0;
M30;
%
 M20 x 1.5
 Thread Length 30 mm

Exercise - 01

PROGRAMO0041
N 100(Rough Turning)
G21 G99 G40
G28 U0.0 W0.0
T0101
G96 S220 M04
G50 S2200
M08
G00 X60.0 Z10.0
G00 X50.0 Z0.0
G71 U0.3 R1.0
G71 P01 Q10U0.0W0.0F0.2
N01 G01 X17.0 Z0.0
N02 G01 X20.0 Z-1.5
N03 G01 X20.0 Z-20.0
N04 G01 X27.0 Z-20.0
N05 G01 X30.0 Z-21.5
N06 G01 X30.0 Z-43.0
N07 G02 X34.0 Z-45.0 R2
N08 G03 X44.0 Z-50.0 R5
N09 G01 X44.0 Z-70.0
N10 G01 X50.0 Z-70.0
G00 X60.0
G00 Z10.0
M05
M09
G28 U0.0 W0.0
N200 (Finish
Turning)
G21 G99
G28 U0.0 W0.0
T0202
G96 S250 M04
G50 S2500
M08
G00 X50.0 Z10.0
G00 Z1.0 F0.2
G01 Z0.0
G42
G70 P01 Q10 F0.15
G00 X60.0
G00 Z10.0
M05
M09
G40
G28 U0.0 W0.0
N300(Grooving)
G28 U0.0 W0.0
T0303
G21 G99 G40
G96 S150 M03
G50 S1600
M08
G00 X60.0 Z10.0
G00 X52.0
Z-18.0
G00 X22.0
G01 X16.0 F0.12
G00 X22.0
G00 X52.0
Z-38.0
G00 X32.0
G01 X26.0 F0.12
G00 X38.0
G00 X52.0
G00 X60.0
Z10.0
M05
M09
G28 U0.0 W0.0
N400(Threading)
G28 U0.0 W0.0
T0404
G21 G40
G97 M04 S800
M08
G00 X60.0 Z10.0
G01 X23.0 Z5.0 F0.2
G76 P010060 Q100
R0.05
G76 X17.0 Z-15.0 P1500
Q200 F2.5
G00 X50.0
Z10.0
M05
M09
G28 U0.0 W0.0
M30
%
We use
P=0.6xThread Pitch

Exercise - 02
1. Centre Drilling
2. Drilling
3. Boring
4. Internal Grooving
5. Internal Threading

Exercise - 03
Tools
3.Grooving
4.O.D. Threading Tool
2

Exercise - 04
Operation
1.Centre Drilling
2.Drilling
3.Boring
4.Grooving
5.I.D. Threading

Exercise - 05
Tools

Tooling and Insert

Safety Symbol
No Smoking. Wear hand protection.
Caution, risk of electric shock. First aid point.

Workshop Safety Rules
Before you can use equipment and machines or attempt practical work in a workshop you
must understand basic safety rules. These rules will help keep you and others safe in the
workshop.
1. Always listen carefully to the teacher and follow instructions.
2. Do not run in the workshop, you could cause an accident.
3. Know where the emergency stop buttons are positioned in the workshop. If you see an
accident at the other side of the workshop you can use the emergency stop button to turn off
all electrical power to machines.
4. Always wear an apron as it will protect your clothes and hold loose clothing such as ties in
place.
5. Wear good strong shoes. training shoes are not suitable.
6. When attempting practical work all stools should be put away.
7. When learning how to use a machine, listen very carefully to all the instructions given by
the teacher. Ask questions if you do not fully understand.
8. Do not use a machine if you have not been shown how to operate it safely by the teacher.
9. Keep hands away from moving/rotating machinery.
10. Use hand tools carefully, keeping both hands behind the cutting edge.
11. Report any damage to machines/equipment as this could cause an accident.

166
Shukla

L-N Key Set
LN key is used for open LN shape
bolt.
LN bolts are more rigid and low
cost.

General Turning Insert

1. Insert Shape
2. Insert Clearance Angle
3. Tolerances
4. Insert Type (Cutting Edge & Clamp)
5. Insert Size
6. Insert Thickness
7. Nose Radius
8. Cutting Edge Condition
9. Hand of Tool
12. Manufacture Option

Turning Tool Holder

Boring Bar Holder

CNC Lathe Operating & Programming

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