This document discusses CNC milling and provides information on: 1. CNC milling uses a prepared program to control the functions and motions of a machine tool. 2. The benefits of CNC milling include high accuracy, short production time, and reduced human error. The drawbacks include high costs and maintenance. 3. It describes various milling operations like profile, drilling, pocket milling, and mirroring operations. It also discusses G-codes and M-codes used in CNC programming.

1. CNC MILLING
(FANUC)

2. COMPUTER NUMERICAL CONTROL(CNC)
INTRODUCTION
Computer numerical control CNC) is one in which
the functions and motions of a machine tool are
controlled by means of a prepared program
containing coded alphanumeric data.
CNC can control the motion of the work piece or
tool, the input parameters such as feed, depth of
cut, speed, and the function such as turning spindle
on / off, coolant on/off.

3. ADVANTAGE AND LIMITATIONS
The benefits of CNC are
a) High accuracy in manufacturing.
b) Short production time.
c) Reduced human error.
d) Simpler fixturing.
The drawback include
a) High Cost.
b) High Maintenance Cost.

4. MILLING OPERTION
 PROFILE MILLING OPERTION.
 DRILLING OPERTION.
 CIRCULAR POCKET MILLING OPERTION.
 RECTANGLE POCKET MILLING OPERTION. .
 MIRRORING OPERATION

5. Part Programming Geometry
Co-ordinate System for a CNC MILLING

6. Machine Zero point (M)

7. Reference Point (R)

8. Character -- ---- Meaning

9. CNC MILLING (MTAB)
Program build-up for CNC MILLING using FANUC
System.
CNC Program can be divided into three parts.
1. Start-up Program
2. Profile Program
3. End of the Program

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

13. CNC LATHE AND MILLING- M-Codes
M-codes are miscellaneous functions that
include actions necessary for machining but
not those that are actual tool movements (for
example, auxiliary functions). They include
actions such as spindle on and off, tool
changes, coolant on and off, program stops,
and similar related functions.

16. M03 SPINDLE ON
CLOCKWISE
M04 SPINDLE ON
COUNTERCLOCKWISE

17. M06 TOOL CHANGE

18. M08 Coolant On or M09 Coolant Off

19. M10 CLAMPS ON
The M10 command turns on the automatic clamps to
secure the workpiece.

20. M11 CLAMPS OFF

21. CNC LATHE AND MILLING- G-Codes
G-codes are
preparatory
fuctios that
iole actual tool
moes (for example,
cotrol of the
machie). These
iclude rapid moes,
feed moes, radial
feed moes, dwells,
ad roughig ad

25. G00: Fast Traverse G01: Linear Traverse

27. Linear and circular interpolation
O1001
G21 G94
G90 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 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
G00 Z5
G91 G28 Z0
G28 X0 Y0
M05
M30

28. Programming using Sub-Program
O1002
G21 G94
G90 G28 Z0
G28 X0 Y0
M06 T1
M03 S1500
G90 G00 X-30 Y-20 Z5
G01 Z0 F100
M98 P52233
G00 Z5
G91 G28 Z0
G28 X0 Y0
M05
M30
O2233
G90 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

29. Drilling operationG73 High speed peck Drilling cycle

31. Drilling Operation on PCD
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 Y35
X-24.748 Y24.748
X-35 Y0
X-24.748 Y-24.748
X0 Y-35
X24.748 Y-24.748
G00 Z5
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

32. Circular Pocket Milling Cycle - Format

34. Rectangular Pocket Milling operation

36. Programming for mirroring operation
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
O1003
G21 G94
G91 G28 Z0
G28 X0 Y0
M06 T1
M03 S1500
M98 P2244
M71
M98 P2244
M81
M70
M98 P2244
M80
M70
M71
M98 P2244
M80
M81
G00 Z5
G91 G28 Z0
G28 X0 Y0
M05