By: Dhyey Shukla

1. Subject:Computer Aided Manufacturing(2171903)
Topic:-NC/CNC Part Programming
Name of Subject Teacher
Mr. Samir Jariwala & Mr.Ankit
Solanki
Department of Mechanical Engineering

2. 1. Introduction
The part programming is
set of machining instruction,
written in standard format,
for the NC/CNC machine.
Type of part programming
1. Manual part programming
2. Computer aided part
programming

3. METHODS OF NC PART
PROGRAMMING
1. Manual part programming
2. Computer assisted part programming
3. Manual data input
4. NC programming using CAD/CAM
5. Computer automated part programming

4. Manual part programming:
The processing instructions are documented on a
form called a part program manuscript.
The manuscript is a listing of the positions of the
tool relative to the workpiece that the machine must
follow in order to perform the processing.
The listing may also include other commands such as
speeds, feeds, tooling, and so on.
A punched tape is then prepared directly from the
manuscript.

5. Computer-assisted part programming,
The programmer prepares the set of processing
instructions in a high-level computer language.
For complex jobs, this computer language is much
easier to use than the lower-level coding required in
manual part programming.
The high-level language commands are interpreted
by the computer, and the required calculations and
data processing are accomplished to prepare the NC
program for the tape reader (or other input device).

6. Manual data input (MDI) :
The NC program is entered directly into the
MCU at the site of the processing machine.
The use of the punched tape is avoided.
The programming procedure is simplified to
permit machine operators rather than part
programmers to do the programming.

8. NC part programming using CAD/CAM
An advanced form of computer-assisted part
programming in which an interactive graphics system
equipped with NC programming software is used to
facilitate the part programming task.
The term CAD/CAM means computer-aided design
and computer-aided manufacturing.
In this method the programmer works on a
CAD/CAM workstation to enter the machining
commands.

9. The actions indicated by the
commands are displayed on the
graphics monitor, which provides
visual feedback to the programmer.
Also, certain portions of the programming cycle are
automated by the NC programming software to
reduce the total programming time required.

10. 5. Computer automated part
programming
It automates the complete part programming task
using software that is capable of making logical
and even quasi intelligent decisions about how
the part should be machined.

11. PUNCHED TAPE IN THE REEL FORM

12. DETAILS OF PUNCHED TAPE

13. Tape Programming Format
Word Address Format
This format is used by most of the NC machines, also
called variable block format. A typical instruction
block will be as below :
N20 G00 X1.200 Y.100 F325 S1000 T03 M09

14. Tab Sequential
Format
Here the alphabets are replaced by a Tab code, which
is inserted between two words.
The MCU reads the first Tab and stores the data in the
first location then the second word is recognized by
reading the record Tab
>20 >00 >1.200 >.100 >325 >1000 >03 >09

15. Fixed Block Format
In fixed block format no letter address of Tab code are
used and none of words can be omitted.
The main advantage of this format is that the whole
instruction block can be read at the same instant,
instead of reading character by character.
This format can only be used for positioning work
only.
20 00 1.200 .100 325 1000 03 09

16. G-Codes (Preparatory Functions)
Code
G00
G01
G02
G03
G20
G21
G24
G28
G29
G32
Function
Rapid positioning
Linear interpolation
Circular interpolation clockwise (CW)
Circular interpolation counterclockwise (CCW)
Inch input (in.)
Metric input (mm)
Radius programming
Return to reference point
Return from reference point
Thread cutting

17. G40
G41
G42
G43
G44
G49
G 53
G54
G84
G90
G91
Cutter compensation cancel
Cutter compensation left
Cutter compensation right
Tool length compensation positive (+) direction
Tool length compensation minus (-) direction
Tool length compensation cancels
Zero offset or M/c reference
Settable zero offset
canned turn cycle
Absolute programming
Incremental programming

18. G-CODE LIST :

20. M-Codes (Miscellaneous
Functions)
Code
M00
M02
M03
M04
M05
M06
M08
M09
Function
Program stop
End of program
Spindle start (forward CW)
Spindle start (reverse CCW)
Spindle stop
Tool change
Coolant on
Coolant off

21. M10
M11
M12
M13
M17
M18
M30
M98
M99
Chuck - clamping
Chuck - unclamping
Tailstock spindle out
Tailstock spindle in
Tool post rotation normal
Tool post rotation reverse
End of tape and rewind or main program end
Transfer to subprogram
End of subprogram

22. CNC PART PROGRAMMING
CNC programmers write instructions for CNC
machines, where a computer is connected
to the mill, along with electrical drives and
sensors for a complete system. This
computer controls the movement of the
machine axis.

23. Input data manual part
programming
1. Sequence Number(N code)
2. Preparatory function (G code)
3. Coordinate function (X,Y,Z,U,V,W AND
I,J,K)
4. Feed function (F)
5. Spindle speed function (S)
6. Tool Function (T)
7. Miscellaneous function (M code)

24. Formats of manual part
programming
• Any part program contains number of laws. The
format is the method of writing the word each
block.
Type of format manual part programming
1. Fixed Sequential Format
2. Block Address Format
3. Tab Sequential Format
4. Word Address Format
Example of word address format:
N001 G90 G01 X40.2 Y50.3 F100 S1000 M07

25. Example of part programme
for turning part
Example part program for component.

26. solution
• N01 M03 S2000
N02 G00 X22 Z2
N03 G01 X21
N04 Z-20 F80
N05 G00 X22 Z0
N06 G01 X20
N07 Z-10 F80
N08 G00 X22 Z2
N09 M30

30. Questions And Suggestion
Are Accepted