CNC milling instruction manual

8/9/2019 CNC milling instruction manual

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MTAB

CNC

MILLING

By

MTAB TECHNOLOGY CENTER PVT (LTD)# 133, DEVELOPED PLOTS, ELECTRICAL & ELECTRONICS INDUSTRIAL ESTATE, CHENNAI - 600096.

Ph.: ++91-44-43111114, Fax: ++91-44-2434 4826, email: [email protected]

Website: www.mtabtraining.com

mailto:[email protected]:[email protected]


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Published by:

MTAB TRAINING CENTRE

Chennai – 600 096

4th Edition: 2005

5th Edition: 2007

6th Edition: 2008

7th Edition: 2009

8th Edition: 2011

9th Edition: 2012

Copyright ©

No part of this publication may be reproduced in any form (including photocopying orstoring in any medium by electronic and whether or not to brief or incidentally to some other

use of this publication), without the prior permission of MTAB, MTAB holds the right to

modify or change any part of the document without notification. The authorized user of this

manual shall acquire no rights in respect of trademarks of other intellectual property rights

referred to herein which are shall remain the property of the owner thereof.


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Table of Content

PART PROGRAMMING FUNDAMENTALS Pg. No

1 PART PROGRAMMING GEOMETRY 1

1.1 Coordinate System for a CNC Milling 1

1.2 Zero points and reference points 4

1.3 CNC Related Dimensioning 8

2 CNC MILLING- PROGRAMMING BUILD-UP 11

2.1 CNC Program Build-up 11

2.2 Part Program Format 12

2.3 Miscellaneous and Preparatory function 13

2.4 Structure of a CNC program 46

3 PROGRAMMING EXAMPLES 48

3.1 Example # 01: Programming using linear and circular

interpolation

48

3.2 Example # 02: Programming using Sub-Program 50

3.3 Example # 03: Programming for Mirroring Operation 52

3.4 Example # 04: Programming for Circular Pocket Milling

Operation

54

3.5 Example # 05: Programming for Rectangular Pocket Milling

Operation

56

3.6 Example # 06: Programming for Drilling Operation 58

3.7 Example # 07: Programming for Drilling Operation on PCD 60

3.8 Example # 08: Programming for Datum Shift Operation using

G54

62

3.9 Example # 09: Programming for Drilling Operation using

Rotation Command ( G68 )

64

3.10 Example # 10: Programming using Scaling Command ( G51 ) 66


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3.11 Example # 11: Programming for Profile Milling Operation

using ATC option

68

3.12 Example # 12: Programming for Profile Milling Operation using

G41

70

3.13 Example # 13: Programming for Profile Milling Operation using

G42

72

4 CNC MILLING - MACHINE ROOM EXERCISES 74

4.1 Ex 01: Study of XL MILL CNC Vertical Machining Centre 75

4.2 Ex 02: Study of tool offset procedures for XL MILL CNC

Vertical Machining Centre

77

4.3 Ex 03: Write a manual part program for machining the

component

82


component

83


component

84


component

85

5 DO’S AND DONT’S FOR CNC MACHINES 86


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Part Programming Geometry MTAB

Coordinate system for a CNC Milling Page | 1

1. Part Programming Geometry

1.1 Coordinate System for a CNC Milling

Machining of a workpiece by a CNC program requires a

coordinate system to be

applied to the machine tool. As all machine tools have more than one slide, it is important

that each slide is identified individually. There are three planes in which movement can take

place.

Longitudinal

Vertical

Transverse

Each plane is assigned a letter and is referred to as an axis, i.e.

Axis X

Axis Y

Axis Z

The three axes are identified by upper case X, Y and Z and the direction of movement along

each axis is specified as either PLUS (+) or MINUS (-). The Z axis is always parallel to the

main spindle of the machine. The X axis is always parallel to the work holding surface, and

always at right angles to the Z axis. The Y axis is at right angles to both Z and X axis FIG. 1

shows the Coordinate System for milling work.

FIG. 1 Co-ordinate System for Milling Work


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The coordinate system for designating the axes is the conventional “Right Hand Coordinate

System” as shown in F1G.2. A labeling of the axes is a Right Hand Coordinate system

whenever the fingers of the right hand are aligned with the positive X axis and are then

rotated (through the smaller angle) toward the positive Y axis, then the thumb of the right

hand points in the direction of the positive Z

axis. Otherwise, the orientation is a 'Left Hand

Coordinate System'.

FIG.2 & 3 Right Hand Co-ordinate Systems

The Right hand coordinate system is also known as 'Clockwise Rotating Coordinate System'.

The reason for this is the sequence of the axis definitions: If the X axis is rotating in the

direction of the Y axis, the movement is the name as if a screw is turned in the Z direction as

shown in FIG. 3

FIG. 4 Clockwise Rotating Co-ordinate System

One could use this right hand to get these alternative relative positions of the same right hand

coordinate system as shown in FIG.4.


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FIG. 5 Co-ordinate System

In programming it must be assumed that the workpiece is stationary and the tools move in the

coordinate system. The workpiece is positioned within the coordinate system so that the Z

axis coincides with the work spindle axis or runs parallel to it.

Some machining operations require programming angles of rotation about one or several

coordinate axes. Rotations about the coordinate axes are identified by the angles of rotation

A, B and C as shown in FIG.5.

FIG. 6 Angles of Rotation and Direction of Rotation


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Zero points and Reference points Page | 4

The direction is positive (+) when the direction of rotation is clockwise as seen from the

Coordinate zero point looking in the direction of the positive axis as shown in the FIG.6

FIG. 7 Examples of Angle of Rotation (swivel angles) on

Machine tool

An example of machine tools with swivel movement of either the workpiece or the tools is

shown in the FIG. 7.

1.2 Zero points and Reference points

On CNC machines, tool traverses are controlled by coordinating systems. Their

accurate position within the machine tool is established by “Zero Points”.

Machine Zero point (M)

This is specified by the Manufacturer of the Machine. This is the zero point for the

coordinate systems and reference points in the machine. The Machine zero point can be the

center of the table or a point along the edge of the traverse range as shown in F1G.8.

The position of the Machine zero point generally varies from Manufacturer to Manufacturer.

The precise position of the machine zero point as well as the axis direction must therefore be

taken from the operating instructions provided for each individual machine.


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FIG.8 Position of the Machine Zero Point

Reference point (R)

This point serves for calibrating and for controlling the measuring system of the

slides and tool traverses. The position of the reference point as shown in FIG.9 is accurately

predetermined in every traverse axis by the trip dogs and limit switches.

FIG. 9 Position of Reference Point on a Milling Machine

Therefore, the reference point coordinates always have the same, precisely known numerical

value in relation to the machine zero point. After initiating the control system, the reference

point must always be approached from all axes to calibrate the traverse measuring system. If


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current slide and tool position data should be lost in the control system as, for example,

through an electrical failure, the machine must again be positioned to the reference point to

re-establish the proper positioning values.

Workpiece Zero Point (W)

This point determines the workpiece coordinate system in relation to the machine

zero point. The workpiece zero point is chosen by the programmer and input into the CNC

system when setting up the machine. The position of the workpiece zero point can be freely

chosen by the programmer within the workpiece envelope of the machine. It is, however,

advisable to place the workpiece zero point in such a manner that the dimensions in the

workpiece drawing can be conveniently converted into coordinate values and orientationwhen clamping / chucking, setting up and checking, the traverse measuring system can be

affected easily. For milled parts, it is generally advisable to use an extreme corner point as the

"WorkPiece Zero Point"

as shown in FIG.10. Occasionally, the workpiece zero point is also

called the “Program zero point”.

FIG.10 Position of Workpiece Zero Point for a Milling Part.

Tool Reference Points

When machining a workpiece, it is essential to able to control the tool point or the

tool cutting edges in precise relationship to the workpiece along the machining path. Since

tools have different shapes and dimensions, precise tool dimensions have to be established

beforehand and input into the control system. The tool dimensions are related to a fixed tool


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setting point during pre-setting. The tool setting point E is located at a certain point on the

tool holder as shown in FIG.11. This setting point permits measuring of tools away from the

CNC machine. The data thus measured such as tool length, tool point offset or tool radius are

input into the tool data storage (memory) of the control system. The mate of the tool setting

point is the Socket point N on the tool carrier. When the tool or tool holder is inserted into

the tool carrier (e.g., turret), the setting point and the tool socket point coincide.

When programming a workpiece contour, it is always the traverse of the tool cutting

edge that is of significance. The tool carrier, e.g., the main spindle on a milling machine,

must then move in a way that the tool cutting edge follows precisely in the desired contour.

FIG.11 Tool Reference Point


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CNC Related Dimensioning Page | 8

1.3 CNC Related Dimensioning

Dimensioning information in a workpiece drawing can be stated in two ways.

Absolute Dimensioning System

Incremental Dimensioning System

1. Absolute Dimensioning System

FIG.12 Absolute System and Incremental System

Absolute dimension system always refers to a fixed reference point in the drawing as

shown in FIG.12. This point has the function of a coordinate zero point as shown in FIG.12.


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The dimension lines run parallel to the coordinate axes and always start at the reference

point. Absolute dimensions are also called as “Reference Dimensioning System”.

Advantages of Absolute Dimensioning System

In case of interruptions that force the operator to stop the machine, the cutting toot

automatically returns to previous position, since it always moves to the absolute

coordinate called for, and the machining proceeds from the same block where it was

interrupted.

Possibility of easily changing the dimensional data in the part program whenever

required.

When describing contours and positions, it is always preferable to employ absolute

dimensions, because the first incorrect dimensioning of an individual point has no

effect on the remaining dimensions and the absolute system is easier to check for

errors.

2. Incremental Dimensioning System

When using incremental dimension system, every

measurement refers to a previously

dimensioned position. Incremental dimensions are distance between adjacent points. These

distances are converted into incremental coordinates by accepting the last dimension point as

the coordinate origin for the new point. This may be compared to a small coordinate system,

i.e., shifted consequently form point to point (P1...P2... through P9) as shown in FIG.12.

Incremental dimensions are also called as “Relative Dimensioning System” or “Chain

Dimensioning System”.

Advantages of Incremental Dimensioning System

If manual programming is used, with incremental systems the inspection of the part

program, before punching the tape, is easy. Since the endpoint, when machining a

part, is identical to the starting point, the sum of the position commands (for each axis

separately) must be zero.

The performance of the incremental system can be checked by a closed-loop tape.

The last position command on the tape causes the table to return to the initial position.


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Mirror – image programming is facilitated with incremental systems.

Incremental dimension programming is advantageous for certain individual partial

contours in a workpiece are repeated several times and the associated program section

can be employed several without a coordinate shift.


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CNC Milling Programming MTAB

CNC Program Built up Page | 11

2. CNC Milling Programming

2.1 CNC Program Build up

In a CNC program, the machining steps (operations) for producing a part on the

machine tool are laid down in a form that the control system can understand. A program is

composed of several blocks. A block is a collection of CNC words. A CNC word is a

collection of address letter and a sequence of numbers. Table.1 shows the address letters

according to DIN 66025.

Table.1 Address Characters As Per DIN 66025

Character Meaning

A Rotation about, X- axis

B Rotation about, Y- axis

C Rotation about, Z axis

D&E Rotation about additional axes

F Feed

G Preparatory function, identifying the action to be executed

H Unassigned

I Interpolation Parameter / Thread pitch parallel to X-axis

J Interpolation Parameter / Thread pitch parallel to Y-axis

K Interpolation Parameter / Thread pitch parallel to Z-axis

L Unassigned

M Machine function / Auxiliary function

N Block number

O Program Number

P,Q,R Parameters are used in cycles

S Spindle speed

T Tool Function

U,V,W Second movement parallel to X, Y, Z axes respectively

X Movement in X-axis

Y Movement in Y-axis

Z Movement in Z -axis


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Part Program Formats Page | 12

All the CNC words may not be used on every CNC machine. Using these words, as an

example, the composition of a block is assembled as follows:

N G X Y Z F S T M ;

In the programming language of a CNC control system, the manufacturer specifies

What instructions can be programmed

What supplementary functions are possible in conjunction with the individual

instruction

What letters and number sequences the instructions and supplementary functions are

formed

When a CNC program is input, the control system checks whether the formal rules of the

programming language have been kept to an instruction. However input of wrong coordinate

values by the programmer can only be found during the program run.

2.2 Part Program Formats

The order in which these words appear in a block of instructions is called the format.

Basically there are two types of format:

Fixed Block Format

Fixed Sequential Format (Fixed block)

Tab Sequential Format (Fixed block)

Word Address Format (Variable block)

Fixed Block Format

a.

Fixed Sequential Format

Every instruction contains all the words in the same sequence irrespective of the words being

the same as in the previous blocks. Hence, the identifying address letter need not be

provided. For example, if some coordinate values (i.e., x, y and z coordinates) remain

constant from one block to next block these values have to be specified in the next block

also. The data must be input in a specified sequence and characters within each word must be

of the same length.


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Part Program Formats Page | 13

Example: N010 G00 X10 Y5 Z0 F60 S1200 EOB

N020 G01 X10 Y5 Z-0.5 F60 S1200 EOB

b. Tab Sequential Format

The words in each instruction / block are always provided in the same sequence but

each word is preceded by the TAB character. If instructions remain unchanged in succeeding

blocks, the instructions need not be repeated but TAB character must be repeated. Here also,

the identifying letter address need not be employed.

Example: N010 G00 X10 TAB Y5 TAB Z0 TAB F60 TAB S800 EOB

N020 G01 X20 TAB Z-0.5 EOB

2. Word Address Format

Each word is preceded and identified by its letter address. This format enables

instructions which remain unchanged from the preceding block, to be omitted from

succeeding blocks. This system reduces programming length, therefore it occupies less

storage space / file size. This is the format adopted by most CNC machine control units.

Detailed format classification is provided by the control system manufacturer.

Example: N010 G00 X10 Y5 Z0 TAB F60 S800 EOB

N020 G01 X20 Z-0.5 EOB

2.3 Miscellaneous and Preparatory Functions

a. Miscellaneous Function (M Codes)

When a 3-digit figure is specified following address M, a 3-digit BCD code signaland a strobe signal are transmitted. These Signals are used for ON/OFF control of a machine

function such as tool change, spindle rotation change, coolant ON/OFF. One M code can be

specified in one block. Selection of M codes for functions varies with the machine tool

builder.


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Miscellaneous and Preparatory Functions Page | 14

Miscellaneous Functions (M Codes)

M Codes Description

M00 Program Stop

M01 Optional Stop

M02 Program End

M03 Spindle Rotation Clockwise

M04 Spindle Rotation Counter Clockwise

M05 Spindle Stop

M06 Tool Change

M08 Coolant On

M09 Coolant Off

M10 Vice Open

M11 Vice Close

M13 Spindle Rotation Clockwise, Coolant On

M14 Spindle Rotation Counter Clockwise, Coolant On

M19 Spindle Orientation

M20 ATC Arm in

M21 ATC Arm out

M22 ATC Arm down

M23 ATC Arm up

M24 ATC draw bar clamping (Manual)

M25 ATC draw bar releasing (Manual)

M27 ATC Reset

M30 Program Stop and Rewind

M70 X – Mirror ON

M71 Y – Mirror ON

M80 X – Mirror OFF

M81 Y – Mirror OFF

M98 Sub-Program Call

M99 Sub-Program Exit

M00 Program Stop

By inserting M00 in a program, the cutting cycle is stopped after the block

containing M00 code. This facility is useful if an inspection check is necessary during

an operation. The cycle is then continued by a cycle start.Example: M00


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M13 Spindle Rotation Clockwise, Coolant On

M13 turns the coolant on and starts spindle rotate clockwise

Example: M13 S1000

M14 Spindle Rotation Counter Clockwise, Coolant OnM14 turns the coolant on and starts spindle rotate counter clockwise

Example: M14 S1000

M19 Spindle Orientation

Ml9 orientates the spindle.

M20 ATC Arm in

M20 moves the ATC arm in. It moves the arm towards the spindle.

M21 ATC Arm out

M21 moves the ATC arm out. It retracts the arm from the spindle.M22 ATC Arm down

M22 moves the ATC arm down.

M23 ATC Arm up

M23 moves the ATC arm up.

M24 ATC draw bar clamping (Manual)

M24 clamps the ATC draw bar

M25 ATC draw bar releasing (Manual)

M25 releases the draw bar.M27 Reset ATC

M27 command used for ATC reset position.


This command is used to stop the spindle, turns the coolant off, terminates and

reset the CNC program.

M32 ATC Rotates Clockwise

M32 command is used to rotate the ATC clockwise

M33 ATC Rotates Counter Clockwise

M33 command is used to rotate the ATC counter clockwise

M38 Door Open

M38 command is used to open the door automatically.

M38 Door Close

M39 command is used to close the door automatically.

M62 Auxiliary output 1 on

M62 sets auxiliary output 1 on. This command mainly used in Flexible

Manufacturing System (FMS) / Computer Integrated Manufacturing (CIM) System.


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M63 sets auxiliary output 2 on. This command mainly used in Flexible


M64 Auxiliary output 1 offM64 sets auxiliary output 1 off. This command mainly used in Flexible



M65 sets auxiliary output 2 off. This command mainly used in Flexible


M70 X Mirror On

M70 command is used for X axis mirroring about the current X axis positionM71 Y Mirror On

M70 command is used for Y axis mirroring about the current Y axis position

M80 X Mirror Off

M80 command is used for X axis mirroring off.

M81 Y Mirror On

M81 command is used for Y axis mirroring off.

M98 Sub-Program Call

M99 Sub-Program Exit

Format: M98 P1112222

Subprogram

Call

Number of

repetition (3 Digit

shown in red color

Subprogram

Number (Four

Digit shown in

blue color


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b. Preparatory Functions (G Codes)

A number following address G determines the meaning of the command for the

concerned block. G codes are divided into the following two types.

One shot G code: The G code is effective only in the block in which it is specified.Modal G code: The G code is effective until another G code of the same group is specified.

Notes on G codes:

G codes marked with * are initial G codes when turning program on. For G20 and

G21, the G code before turning power off remains.

G codes of group 00 are not modal. They are only effective in the block in which theyare specified.

If any G code of group 01 is specified in a canned cycle mode, the canned cycle is

automatically cancelled and the G80 condition is entered. However a G code of group

01 is not affected by any of the canned cycle G codes.

G CODE Group Function

G00*

01

Positioning (Rapid traverse)

G0l* Linear interpolation (Cutting feed)

G02 Circular interpolation (Clockwise)

G03 Circular interpolation ( Counter Clockwise)

G04 00 Dwell, Exact stop

G17*

02

XY plane selection

G18 ZX plane selection

G19 YZ plane selection

G20 06 Input in inch

G21 Input in mm

G28 00 Return to reference point

G40*

07

Cutter radius compensation cancel

G41 Cutter radius compensation leftG42 Cutter radius compensation right

G43 Tool length compensation + direction


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G44 08 Tool length compensation - direction

G49* Tool length compensation cancel

G50 11 Scaling Off

G51 Scaling On

G54 14 Datum Shift

G68 16 Rotation On

G69 Rotation Off

G73

09

High speed peck drilling cycle

G74 L.H. Tapping cycle

G76 Fine boring

G80* Canned cycle cancel

G81 Continuous drilling cycle, spot drilling

G82 Continuous drilling cycle, drilling with

dwell

G83 Peck drilling cycle

G84 R.H.Tapping cycle

G85 Boring cycle with feed retraction

G86 Boring cycle with rapid retraction

G87 Back Boring cycle

G88 Boring cycle

G89 Boring cycle with dwell and feed retraction

G90* 03 Absolute coordinate system

G91 Incremental coordinate system

G94 05 Feed per minute

G95 Feed per revolution

G98* 10 Return to initial point in a canned cycle

G99 Return to R point in a canned cycle


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G00: Fast Traverse

A G00 moves the tool to a certain position in the work coordinate system with an absolute

command or to a position specified distance from the current position with an incremental

command at a rapid traverse rate.

Format: G00 X_ _ Y _ _ Z _ _

Example: G00 X20 Y30 Z10

Here the tool is moved to X30mm, Y30mm and Z10mm

Notes on G00:

The rapid traverse rate in the G00 command is set for each axis independently by the

machine tool builder. Accordingly, the rapid traverse rate cannot be specified in the

address F.

In the positioning mode actuated by G00, the tool is accelerated to a predetermined

speed at the start of a block and is decelerated at the end of block. Execution proceeds

to the next block after confirming the in-position.


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Sl.No: Data to be

given

Command Command Meaning

01. Plane Selection

G17 Arc specification

on XY Plane


on ZX Plane


on YZ Plane

02. Direction of

Rotation

G02 Clockwise (CW)

G03

Counter

Clockwise(CCW)

03. End Point G90 Mode Two of the X, Y and

Z axes

End point position

in the WorkCoordinate system

Position G91 Mode Two of the X, Y and

Z axes

Distance from start

point to end point

04. Distance from start point to

centre

Two of the I, J and K

axes

The signed

distance from start

point to centre

ARC Radius R Arc radius

05. Feed Rate F Velocity along arc

The view is from the positive direction of the Z axis (Y axis or X axis) to the negative

direction on XY plane (ZX plane or YZ plane) in the right hand cartesian coordinate system.

Fig. shows the CW and CCW directions in different plane. The end of an arc is specified by

address X, Y or Z and is expressed as an absolute or incremental value according to G90 or

G91. For the incremental value, the coordinate of the end point which is viewed from the

start point of the arc is specified.

The arc centre are specified by addresses I, J and K for the X, Y and Z axes

respectively. The numerical value following I, J and K however is a vector component in

which the arc centre is seen from the start point, and is always specified as an incremental

value irrespective of G90 and G91, as shown in fig. I, J and K must be signed according to

the direction. The radius can be specified with address R instead of specifying the centre by I,

J and K. when an arc is exceeding 180º is commanded, the radius must be negative value.


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G04 Dwell

The command G04 causes the program to wait for a specified amount of time. The

time can be specified in seconds with the “X” prefixes or in milliseconds with the “P” prefix.

One of the uses of this code is to get a sharp corner on the profile of the workpiece in cutting

feed. It is also used at the end of drilling cycle. During cutter motion, a deceleration at the

end of the motion specified by one statement and acceleration at the start of the motion

specified by the next statement are usually applied automatically by the controller.

Example: G04 X1.5

G04 P1500

G20 Inch mode input

All input parameters will be taken as imperial values. That is, they will specify

inches.

G21 metric mode input

All input parameters will be taken as metric values. That is, they will specify

millimeters.

G28 Go to Reference point

This command specifies automatic return to the reference point for the specified axes.

The coordinates defined in this command is an intermediate coordinate and is commanded by

absolute or incremental value. The G28 block is used to position the tool at the intermediate

point of all specified axes at the rapid traverse speed, and then move to the reference point at

the rapid traverse rate. In general this command is used for automatic tool changing. For


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safety reasons the cutter radius compensation, and tool length compensation should be

canceled before executing this command.

Example: G91 G28 X0 Y0 Z0 – Makes the cutting tool to move to Reference point directly.

G40 Cutter radius Compensation Cancel

The commands G40 deactivate the cutter radius compensation.

G41 Cutter radius Compensation Left

The command G41 activate tool radius compensation left, tool operates in machining

operation to the left side of the profile or contour (Fig.a)

G42 Cutter radius Compensation Right

The command G42 activate tool radius compensation right, tool operates inmachining operation to the right side of the profile or contour (Fig.b)

G50 Scaling Off: This command enables cancel the scaling command.

G51 Scaling On: This command enables the size of the profile size to be increased or

decreased.

G54 Datum Shift: T his command is used to shift the profile along X axis or Y axis.

G68 Rotation On: This command can rotate a programmed shape at a specified angle.

G69 Rotation Off: This command enables cancel the coordinate system rotation.


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Canned Cycles

To simplify programming, the canned cycle command can execute the specific

operation using one G code, instead of several separated G code commands in the program.

Operation Description

1. Positioning of X & Y axes (Initial point)

2. Rapid traverse to R point

3. Hole machining

4. Operation at the bottom of hole

5. Retraction to R point

6. Retraction to the initial point

The G codes from G73 to G89 are reserved for various canned cycles. It may be

drilling, boring, tapping etc.

In general, canned cycle consists of six operations as shown below.


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Return to initial point / R point in a canned cycle (G98 / G99)

Programming Format for canned cycle:

G98 G _ X _ Y _ Z _ R _ Q _ P _ F _ K _

G99

Explanation of the parameters

G98 - Return to initial point in a canned cycle

G99 - Return to R point in a canned cycle

The other parameters would be explained in the specific canned cycle.

Function:


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G73 High speed peck Drilling cycle

Programming Format:

G98 G73 _ X _ Y _ Z _ R _ Q _ P _ F _ K _

G99


X Y Drilling position of the X & Y axes

Z Depth of the drilling

R Z coordinates of the R point

Q Depth of cut for each peck (always incremental value)

P Dwell time at the bottom of the drilling

F Feed rate

K Number of drill positions


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Function

When drilling a deep hole, the drill should be retracted occasionally to avoid

congestion of chips between the hole and the drill. Since the Z axis direction intermittent feed

simplifies chip disposal and permits a very small retraction value to be set in deep wholedrilling, efficient machining is performed. Here the retraction is performed at the rapid rate.

Example: M03 S1200

G90 G00 X10 Y10 Z10

G99 G73 X10 Y10 Z-2 R1 P500 Q1 F80 K1

G80

G74 L.H. Tapping cycle

Programming Format:

G98

G74 _ X _ Y _ Z _ R _ P _ F _ K _

G99






F Thread lead

K Number of tapping positions


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Operation Sequence

1) Rapid position to X, Y and Z (the Initial level).

2) Rapid traverse to R point level.

3) Feed to Z depth.

4) Dwell P (time for spindle stop and start CW direction).

5) Feed to R point level.

6) Dwell P (time for spindle stop and start CCW direction).

Note: During G74, the feed rate override is ignored and the cycle does not stop until the end

of the return operation, even if a feed hold is applied.

Example: M04 S200

G90 G00 X10 Y10 Z10

G99 G74 X10 Y10 Z-12 R1 P500 F80

G80


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G76 Fine boring

Programming Format:

G98

G76 _ X _ Y _ Z _ R _ F _ P _ I _ J _ K _

G99






I Shift amount along X axis at the bottom of a hole

J Shift amount along Y axis at the bottom of a hole

F Thread lead

K Number of boring positions


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Function:

This cycle is commanded in single block. Since a spindle oriented stop is performed

at the bottom of the hole and the spindle retracts after shifting in the direction opposite to the

cutter-direction, high precision and efficient boring is performed without scratching the work

piece.

Note: the shift value is specified by Q. the Q value is always a positive value. If a negative

value is specified, the sign is ignored. The Q value is modal in the canned cycle.

Example: M03 S200

G90 G00 X0 Y20 Z10

G99 G76 X20 Y20 Z-16 Q0.5 R-10 F60

G80 canned cycle cancel

G80 is canned cycle cancelled. Meanwhile, the point R and the point Z are all

cancelled.

G81 Continuous drilling cycle, Spot drilling cycle

Programming Format:

G98

G81 _ X _ Y _ Z _ R _ F _ K _

G99





F Feed rate



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CNC Milling



Function

G81 command can be used to drill a hole. The tool is moved with feed rate when it is

drilling a hole. Then, the tool is moved at the rapid rate when it is retracting from the bottom

of the hole.

Example: M03 S1200

G90 G00 X0 Y20 Z10

G99 G81 X20 Y20 Z-8 R1 F60 K1

G82 Continuous drilling cycle with dwell

Programming Format:

G98

G82 _ X _ Y _ Z _ R _ P _ F _ K _

G99






F Feed rate


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Function

G82 command can be used to drill a counter bore.

Example: M03 S1200

G90 G00 X0 Y20 Z10

G99 G82 X20 Y20 Z-8 P500 R1 F60 K1

G83 Peck drilling cycle

Programming Format:

G98

G83 _ X _ Y _ Z _ R _ Q _ P _ F _ K _

G99





Q Depth of cut for each peck (always incremental value)



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CNC Milling



F Feed rate


Function

G83 command can perform a peck drilling. The intermittent feed allows the operator

to remove the chips from the drill.

Example: M03 S1200

G90 G00 X10 Y10 Z10

G99 G83 X10 Y10 Z-2 R1 P500 Q1 F80 K1

G80

G84 R.H.Tapping cycle

Programming Format:

G98

G84 _ X _ Y _ Z _ R _ P _ F _ K _

G99






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CNC Milling




F Thread lead

K Number of tapping positions

Function

R.H Tapping is performed by spindle rotation clockwise. Then the spindle turns

counter clockwise for retraction when the tool reaches the bottom of the hole.

Note: During G84, the feed rate override is ignored and the cycle does not stop until the end

of the return operation, even if a feed hold is applied.

Example: M03 S200

G90 G00 X10 Y10 Z10

G99 G84 X10 Y10 Z-12 R1 P500 F80

G80


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G85 Boring cycle with feed retraction

Programming Format:

G98 G85 _ X _ Y _ Z _ R _ F _ K _

G99





F Feed Rate


Function

G85 command is used to increase diameter of the previous drilling.


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CNC Milling



G86 Boring cycle with rapid retraction

Programming Format:

G98 G86 _ X _ Y _ Z _ R _ F _ K _

G99





F Feed Rate


Function

G86 command is used to increase diameter of the previous drilling.


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CNC Milling



G87 Back Boring cycle

Programming Format:

G98 G87 _ X _ Y _ Z _ R _ F _ K _

G99





F Feed Rate


Function

G87 command is used to bore a pervious drill hole.


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G88 Manual Back Boring cycle

Programming Format:

G98 G87 _ X _ Y _ Z _ R _ P _ F _ K _

G99





P Dwell time at the bottom of the hole

F Feed Rate


Function:

G88 command can be used to bore a hole precisely. The main difference is that the

tool is returned to the initial point or the point R in the manual mode key (On the machine

control panel).


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CNC Milling



G89 Boring cycle with dwell and feed retraction

Programming Format:

G98 G89 _ X _ Y _ Z _ R _ P _ F _ K _

G99





P Dwell time at the bottom of the hole

F Feed Rate


Function

G89 command is used to bore a pervious drill hole.


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CNC Milling



G90 Absolute coordinate system

The coordinate values of the point with reference to the origin of the drawing.

G91 Incremental coordinate system

The coordinate values of the point with reference to the previous position of thedrawing.

G94 Feed per minute

This G code defines Feed per Minute. The unit is mm / min.

G95 Feed per revolution

This G code defines Feed per Revolution. The unit is mm / rev.

G98 Return to initial level & G99 Return to R point level in Canned Cycle


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CNC Milling



Canned Cycles

G code Drilling

(-Z direction)

Operation at the

bottom of a hole

Retraction

(+Z direction)

Application

G73 Intermittent

feed

_ Rapid traverse High speed peck

drilling cycle

G74 Feed Dwell Spindle

CW

Feed Left hand

tapping

G76 Feed Oriented spindle

stop

Rapid traverse Fine boring cycle

G80 - _ _ Cancel

G81 Feed _ Rapid traverse Drilling cycle,

spot drilling

cycle

G82 Feed Dwell Rapid traverse Drilling cycle,

counter drilling

cycle

G83 Intermittent

feed

_ Rapid traverse Peck drilling

cycle


CW

Feed Tapping cycle

G85 Feed _ Feed Boring cycle

G86 Feed Spindle stop Rapid traverse Boring cycle

G87 Feed Spindle CW Rapid traverse Back boring

cycle


Stop

Manual Boring cycle

G89 Feed Dwell Feed Boring cycle


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Machining Cycles

Circular Pocket Milling Cycle - Format

G170 P Q R X Y Z I J K

G171 P S R F B J

P0 - ROUGHING OPERATION

P1 - FINISHING OPERATION

Q - DEPTH OF CUT FOR EACH PASS

R - REFERENCE POINT

X - POSITION OF TOOL IN X AXIS

Y - POSITION OF TOOL IN Y AXIS

Z - TOTAL DEPTH

I - SIDE FINISHING ALLOWENCE

J - BASE FINISHING ALLOWENCE

K - RADIUS OF THE POCKET

P - CUTTER MOVEMENT IN %, i.e., 50% OF THE CUTTER Dia.

S - ROUHING OPERATION SPINDLE SPEED

R - ROUGHING OPERATION FEED IN Z AXIS

F - ROUGHING OPERATION FEED IN X & Y AXES

B - FINISHING OPERATION SPINDLE SPEED

J - FINISHING OPERATION FEED IN X, Y & Z AXES


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Rectangular Pocket Milling Operation - Format

G172 P Q R X Y Z I J K

G173 I K P S T R F B J Z

P0 - ROUGHING OPERATION

P1- FINISHING OPERATION

Q - DEPTH OF CUT FOR EACH PASS

R - REFERENCE POINT

X - RECTANGULAR POCKET X AXIS LEFT CORNER

Y - RECTANGULAR POCKET Y AXIS LEFT CORNER

Z - TOTAL DEPTH

I - TOTAL LENGTH IN X AXIS

J - TOTAL LENGTH IN Y AXIS

K - CORNER RADIUS OF THE POCKET

I - SIDE FINISHING ALLOWENCE

K - BASE FINISHING ALLOWENCE

P - CUTTER MOVEMENT IN %, i.e., 50% OF THE CUTTER Dia.

S - ROUGHING OPERATION SPINDLE SPEED

T - TOOL NUMBER

R - ROUGHING OPERATION FEED IN Z AXIS

F - ROUGHING OPERATION FEED IN X & Y AXES

B - FINISHING OPERATION SPINDLE SPEED

J - FINISHING OPERATION FEED IN X, Y & Z AXES

Z - SAFETY POSITION


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Structure of a CNC Program Page | 46

2.4 Structure of a CNC program

CNC Program can be divided into three parts.

1. Start-up Program

2. Profile Program

3. End of the Program

1. Start-up Program

O1000

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G00 X0 Y0 Z5

Explanation:

O1000 While writing a program on FANUC controller first line has to be started with letter “O” followed by four digit number which

specifies the program number.

G21 G94 G21 - specifies that program is done in metric units

G94 gives the unit of feed in mm / min

G91 G28 Z0 Makes the tool to go to home position in incrementally

G28 X0 Y0 Makes the tool to go to home position. U & W are secondary

movements about x and z axes.

M06 T1 Tool Change with tool position No: 1

M03 S1500 Makes the spindle rotation in clockwise with spindle rotates at

1500 RPM

G00 X0 Y0

Z5

G00 gives rapid position of the tool to a point X0 Y0 Z5. This is

just above the billet. This point is called as the Tool entry Point.


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Structure of a CNC Program Page | 47

2. Profile Program: Profile program is based on the given part drawing.

3. End of the Program

G91 G28 Z0

G28 X0 Y0

M05

M30

G91 G28 Z0 Makes the tool to go to home position in incrementally

G28 X0 Y0 Makes the tool to go to home position in incrementally along X

and Y axes

M05 Stop the Spindle



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Programming Examples MTAB

Example Program Page | 48

3. Programming Examples

3.1 Example # 01: Programming using linear and circular interpolation

Write a manual part program for Profile Milling Operation for the component shown

in DWG.NO: 01.

DWG.NO: 01

PLANNING AND OPERATIONS SHEET

BILLET SIZE: 90 x 90 x 10 MATERIAL: Aluminium

PROGRAM NO: O1001 DWG. NO: 01

Sl.No: Operation Tool Type Tool

Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1001

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X-30 Y-20 Z5

G01 Z-1 F100

G01 X-30 Y20

G02 X-20 Y30 R10G01 X20 Y30

G03 X30 Y20 R10

G01 X30 Y-20

G01 X20 Y-30

G01 X-20 Y-30

G03 X-30 Y-20 R10

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30


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CNC Milling



3.2 Example # 02: Programming using Sub-Program

Write a manual part program for Profile Milling Operation using Sub-Program for the

component shown in DWG.NO: 02.

DWG.NO: 02


BILLET SIZE: 90 x 90 x 10 MATERIAL: Aluminum



Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling using

Sub-Program

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1002

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X-30 Y-20 Z5

G01 Z0 F100

M98 P52233

G00 Z5G91 G28 Z0

G28 X0 Y0

M05

M30

O2233

G91 G01 Z-1 F100

G90 G01 X-30 Y20

G02 X-20 Y30 R10

G01 X20 Y30

G03 X30 Y20 R10

G01 X30 Y-20

G01 X20 Y-30

G01 X-20 Y-30

G03 X-30 Y-20 R10

M99


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CNC Milling



O1003

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1M03 S1500

M98 P2244

M70

M98 P2244

M80

M71

M98 P2244

M81M70

M71

M98 P2244

M80

M81

G00 Z5

G91 G28 Z0

G28 X0 Y0M05

M30

O2244

G90 G00 X15 Y15 Z5

G01 Z-1 F100

G01 X15 Y25

G01 X25 Y25

G01 X25 Y15

G01 X15 Y15

G00 Z5

G00 X0 Y0

M99


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3.4 Example # 04: Programming for Circular Pocket Milling operation

Write a manual part program for Circular Pocket Milling Operation for the


DWG.NO: 04





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Circular

Pocket

MillingOperation

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1004

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X0 Y0 Z5

G170 P0 Q1 R0.5 X0 Y0 Z-4 I0.1 J0.1 K25

G171 P50 S1200 R60 F100 B1500 J60

G170 P1 Q1 R0.5 X0 Y0 Z-4 I0 J0 K25G171 P50 S1200 R60 F100 B1500 J60

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30


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CNC Milling



3.5 Example # 05: Programming for Rectangular Pocket Milling operation

Write a manual part program for Rectangular Pocket Milling Operation for the


DWG.NO: 05


BILLET SIZE: 90 x 90 x 10 MATERIAL: AluminiumPROGRAM NO: O1005 DWG. NO: 05


Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Rectangular

Pocket

Milling

Operation

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1005

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X0 Y0 Z5

G172 P0 Q1 R0.5 X-25 Y-17.5 Z-4 I50 J35 K0

G173 P50 S1200 T1 R60 F100 B1500 J60 Z5 I0.1 K0.1

G172 P1 Q1 R0.5 X-25 Y-17.5 Z-4 I50 J35 K0G173 P50 S1200 T1 R60 F100 B1500 J60 Z5 I0 K0

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30


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3.6 Example # 06: Programming for Drilling operation

Write a manual part program for Drilling Operation for the component shown in

DWG.NO: 06.

DWG.NO: 06



PROGRAM NO: O1006 DWG. NO: 06Sl.No: Operation Tool Type Tool

Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Drilling

Operation

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1006

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X25 Y25 Z5

G01 Z2 F100

G73 G99 X25 Y25 Z-5 Q1 R0.5 F80 K1

X-25 Y25X-25 Y-25

X25 Y-25

G00 Z5

G80

G91 G28 Z0

G28 X0 Y0

M05

M30


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3.7 example # 07: Programming for Drilling Operation on PCD

Write a manual part program for Drilling Operation on PCD Operation for the


DWG.NO: 07




Sl.No: Operation Tool

Type

Tool

Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Drilling on

PCD

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1007

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X35 Y0 Z5

G73 G99 X35 Y0 Z-5 Q1 R0.5 F80 K1

X24.748 Y24.748

X0 Y35X-24.748 Y24.748

X-35 Y0

X-24.748 Y-24.748

X0 Y-35

X24.748 Y-24.748

G00 Z5

G80

G91 G28 Z0

G28 X0 Y0

M05

M30

X = PCD / 2 SIN45°= 70 / 2 SIN45°

= 24.748

Y = PCD / 2 COS45°

= 70 / 2 COS45°

= 24.748


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3.8 Example # 08: Programming for Datum Shift Operation using G54

Write a manual part program for Datum Shift Operation for the component shown in

DWG.NO: 08.

DWG.NO: 08





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Program

using

Datum Shift

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1008

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X10 Y10 Z5

G54 X10 Y10

M98 P5566

G00 Z5G90 G00 X-30 Y10

G54 X-30 Y10

M98 P5566

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30

O5566

G90 G00 Z-1 F100

G01 X0 Y10

G01 X10 Y10

G01 X10 Y0

G01 X0 Y0

G00 Z5

G54 X0 Y0

M99


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CNC Milling



3.9 Example # 09: Programming for Drilling operation using Rotation Command (G68)

Write a manual part program for Drilling Operation using Rotation command for the


DWG.NO: 09





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Drilling

using G68Command

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1009

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1M03 S1500

G90 G00 X35 Y0 Z5

G68 R0

M98 P6677

G68 R45

M98 P6677

G68 R90

M98 P6677G68 R135

M98 P6677

G68 R180

M98 P6677

G68 R225

M98 P6677

G68 R270

M98 P6677G68 R315

M98 P6677

G00 Z5

G69

G91 G28 Z0

G28 X0 Y0

M05

M30

O6677

G73 G99 X35 Y0 Z-5 Q1 R0.5 F80 K1

G00 Z5

G80

M99


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CNC Milling



3.10 Example # 10: Programming using Scaling Command

Write a manual part program for Scaling Command for the component shown in

DWG.NO: 10.

DWG.NO: 10





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Scaling

Operation

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1010

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1M03 S1500

M98 P7777

G90 G00 Z5

M98 P8888

G90 G00 Z5

G91 G28 Z0

G28 X0 Y0

M05M30

O7777

G90 G00 X-30 Y-20 Z5

G01 Z-1 F100

G01 X-30 Y20

G02 X-20 Y30 R10

G01 X20 Y30

G03 X30 Y20 R10G01 X30 Y-20

G01 X20 Y-30

G01 X-20 Y-30

G03 X-30 Y-20 R10

M99

O8888

G51 P0.5

M98 P7777

G00 Z5

G50

M99


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3.11 example # 11: Programming for Profile Milling using ATC option

Write a manual part program for Scaling Command for the component shown in

DWG.NO: 11.

DWG.NO: 11




Sl.No: Operation Tool Type ToolDia.,

mm

ToolStation

No.1

ToolLength

Offset

No.1

SpindleSpeed,

RPM

Feed,mm/min

1 Profile

Milling

Operation

Slot Drill

Cutter

6 1 1 1500 100

2 Profile

Milling

Operation

Slot Drill

Cutter

10 2 2 1200 80


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CNC Milling



O1011

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 X-30 Y-20 Z5

G01 Z-1 F100

G01 X-30 Y20

G02 X-20 Y30 R10G01 X20 Y30

G03 X30 Y20 R10

G01 X30 Y-20

G01 X20 Y-30

G01 X-20 Y-30

G03 X-30 Y-20 R10

G00 Z5

G91 G28 Z0

G28 X0 Y0

M06 T2

M03 S1200

G90 G00 X-20 Y0 Z5

G01 Z-1 F100

G02 X20 Y0 R10

G02 X-20 Y0 R10

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05M30


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CNC Milling



3.12 Example # 12 Programming for Profile Milling Operation using G41

Write a manual part program for Profile Milling Operation with cutter radius

compensation left (G41) for the component shown in DWG.NO: 12

DWG.NO: 12




Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling

Operation

Using G41

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1012

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 G41 X0 Y0 Z10

G01 X-30 Y-20 F100

G01 Z5 F100

G01 Z-1 F100G01 X-30 Y20

G02 X-20 Y30 R10

G01 X20 Y30

G03 X30 Y20 R10

G01 X30 Y-20

G01 X20 Y-30

G01 X-20 Y-30

G03 X-30 Y-20 R10

G01 X-30 Y0

G40

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30


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CNC Milling



3.13 example # 13: Programming for Profile Milling Operation using G42

Write a manual part program for Profile Milling Operation with cutter radius

compensation right (G42) for the component shown in DWG.NO: 13.

DWG.NO: 13




Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling

Operation

Using G42

Slot Drill

Cutter

6 1 1 1500 100


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CNC Milling



O1013

G21 G94

G91 G28 Z0

G28 X0 Y0

M06 T1

M03 S1500

G90 G00 G42 X0 Y0 Z10

G01 X30 Y-20 F100

G01 Z-1 F100

G01 X30 Y20G02 X20 Y30 R10

G01 X-20 Y30

G03 X-30 Y20 R10

G01 X-30 Y-20

G02 X-20 Y-30 R10

G01 X20 Y-30

G01 X30 Y-20

G01 X30 Y0

G40

G00 Z5

G91 G28 Z0

G28 X0 Y0

M05

M30


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CNC Milling

Machine Room Exercises MTAB

Page | 74

CNC Milling

Machine Room Exercises


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CNC Milling


Page | 75

Ex # 01: Study of XL MILL CNC Vertical Machining Centre

Write down the Specifications of the XLMILL

Specifications Units XLMILL

Travels

X Axis Travel mm 225

Y Axis Travel mm 150

Z Axis Travel mm 115

Distance Between Table Top

and Spindle Nose

70 - 185

Table

Table Size mm 360 x 132

Spindle

Spindle Motor Capacity HP 0.5

Programmable Spindle

Speed

rpm 150 - 4000

Spindle Nose Taper - BT 30

Accuracy

Positional Accuracy mm 0.01

Repeatability mm ± 0.005

Feed Rate

Rapid Traverse X x Y x Z

axes

m / min 1.2

Programmable Feed Rate on

X x Y x Z axes

mm / min 0 - 1200

ATC

Tool Storage Capacity Pcs 6

Maximum Tool Diameter mm 16

Maximum Tool Length mm 40


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CNC Milling


Page | 76

ATC Direction - Bi-Directional

Slides

Slides Hardened Ground Guide waysBall Screws X, Y and Z axes Dia. & Pitch 16mm x 5mm

CNC

Control System - PC Based 3 Axes Continuous

Path

Lubrication

Lubrication System Centralized Lubrication System

Power Source

Main Supply 230v, Single Phase, 50Hz

Machine Dimensions

Height x Length x Depth mm 1000 x 575 x 650Machine Weight kg 170

Optional Accessories

CAM Software, Offline Programming Software, Auto Door, Hydro Pneumatic

Vise, Work Bench, 3 axis Loading / Unloading Arm, 6 station ATC, Stabilizer,

Air Compressor

Features

Compatible / Upgradable - FMS / CIM System


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CNC Milling


Page | 77

Ex # 02: Study of Tool Offset Procedures for XL MILL CNC Vertical Machining

Centre

Tool offset procedures:Select Tool Offsets from Job/Tooling Main Menu.

After Selecting Tool offsets the following window appears. Choose required tool

position and Double Click on it. The following window appears on the screen.

Manually enter TOOL RAD and ACTUAL DIAM.

Then Add Tool To Library. The following window appears and Click OK on CNC

TRAINER SETTINGS.

The Selected Tool should be brought either rapidly or manually Nearer to the left

edge of the billet using all the three axes.


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CNC Milling


Page | 78

Then Click on the SPDL CW with S 1500 RPM

Move the Tool in JOG Mode with Appropriate Displacement until tool touches the

edge of the billet as shown below.

Now Select DATUM and then Click X axis on the CNC DISPLAY which will turn

into ZERO indicating the point has been made Zero in X axis.


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CNC Milling


Page | 79

Lift the Tool away from the billet by using Manual mode equal to the radius of the cutter in

X + direction and Select Datum and Click on X axis on the CNC DISPLAY which will turn

into ZERO indicating the point has been made Zero in X axis.

Repeat the Procedure for taking the Offset in Y axis also.

For taking Z axis offset, bring the cutter to the surface of the billet by using JOG Mode. As

the cutter touches the billet Select Datum and Click on Z axis on the CNC DISPLAY which

will show Zero.

Offset for all the subsequent tools in Z axis are to be taken based on the Length of first tool.

Procedures:

Select Tool Offsets from Job/Tooling Main Menu.


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Select Tool Type as per the Program and Select Tooling form CNC TRAINER

SETTINGS; choose required tool and Double Click on it. The following window

appears on the screen.

For taking Z axis offset, bring the cutter to the surface of the billet by using JOG Mode. As

the cutter touches the billet lick on Z LENGTH on the CNC TRAINER SETTING which will

show offset value with respect to first tool.


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NOTE:

X and Y offsets remains same for all the tool


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Ex # 03: Write a manual part program for machining the component shown in

DWG.NO: 03.

Profile Depth: 5 mm Depth of cut for each pass: 1 mm

DWG.NO: 03



PROGRAM NO: 03 DWG. NO: 03


Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling

Operation

Slot Cutter 6 1 1 1500 100


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DWG.NO: 04.


DWG.NO: 04





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Profile

Milling

Operation

Slot Cutter 6 1 1 1500 100


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DWG.NO: 05.


DWG.NO: 05





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Drilling

Operation

Slot Cutter 6 1 1 1500 100

2 Drilling

Operation

Slot Cutter 10 2 2 1200 80


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DWG.NO: 06.

DWG.NO: 06





Dia.,

mm

Tool

Station

No.1

Tool

Length

Offset

No.1

Spindle

Speed,

RPM

Feed,

mm/min

1 Circular

Pocket

Milling

Operation

Slot Cutter 12 1 1 1500 100


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MTAB

Page | 86

DO’S AND DONT’S FOR CNC MACHINES

“DONT’S”

Never Open Guard Doors While Machine is in Running

Never Attempt to Bypass Guard Interlock, Safety Devices etc.

Never Leave Machine Unattended While in Running

Never Adjust Tooling or Coolant While Machine is Running

Never Use Broken or Worn Tooling

Never Remove any Warning or Instruction Tags from Machine

Never Operate any Equipment if unusual or Excessive Noise Vibration Occurs

Never Remove Chips with the Hands

Never Remove or load Work pieces While Machine is in Motion

Never Allow the Operation or Repair of Equipment by Untrained Personnel

Never Leave Tools or other items on the Machine

Never Touch Electrical Equipment When Hands are Wet


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MTAB

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“DO’S”

Always make sure all Tools are Securely Clamped in Position

Always Consult your Authority when in Doubt

Always make sure all Tool Mounting Surfaces are clean before Mounting Tools

Always Replace Blown Fuses with Fuses of the Same Capacity

Switch off Power during Maintenance / Repair work

Negligence on the above points can cause Personal Injury and Machine Damage


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