The document contains 16 questions asking to write NC programs for various components. The questions cover topics like interpreting an NC program block by block, writing manual and APT programs for milling and turning operations, writing subroutines, and selecting cutting parameters like spindle speed and feed rates. Programs are to be written for operations like facing, roughing, finishing and drilling on materials like aluminum, steel and copper alloys. Dimensions and figures of the components are provided along with relevant cutting data.

1. Final Year B.Tech. (Mechanical)
CAD/CAM -Assignment No.5 &6
Submission date – 10-4-2012
1-20
1. Interpret the following NC program block by block. Plot the complete tool center
path with the corresponding coordinates. Mark the corresponding NC blocks on
tool path segment.
N01 G90 N11 G03 X180 Y122.5 I-57.5
N02 G71 N12 G01 X107.5
N03 G92 X-12.5 Y-12.5 Z50 N13 Y110
N04 G00 Z2.5 M03 S800 N14 G0-2 X80 Y82.5 I-27.5
N05 G01 Z-7.5 F25 M08 N15 G01 X40
N06 X162.5 F125 N16 G03 X-12.5 Y30 J-52.5
N07 Y0 N17 G01 Y-12.5
N08 G02 X220 Y57.5 I57.5 N18 Z3.8
N09 G01 X232.5 N19 G00 Z50 M09 M05
N10 Y70 N20 M30
2. For the component shown in fig., write manual part program.
(P.N.Rao page 363, Fig.13.41)
Material- C 20 steel
Milling cutter – φ20 mm
3. For the component shown in fig., write APT program.
(P.N.Rao page 495, Fig.16.80)
Material- C 20 steel (12 mm thick)
Milling cutter – φ20 mm
Data for milling
Work material Hardness HSS
BHN Speed Feed
m/min mm/rev
C20 steel 110-160 20 0.13
Data for drilling
Work material Hardness HSS
BHN Speed Feed
m/min mm/rev
C20 steel 110-160 35 0.2-0.5
4. Write APT program for the component shown in fig. with the same data.
(P.N.Rao page 493, Fig.16.77)

2. 21-40
5. Write manual part program for the component shown in fig.1.
Tools used – 1) Rough turning (max. depth of cut = 0.1”)
2) Finish turning ( max. depth of cut = 0.02”)
Data for turning
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
Aluminium 70-105 120 0.28 240 0.25
Fig.1
6. For the component shown in fig.2 (thickness = 0.4 inch), write manual part
program. Dimensions are in inches.
Material- C80 steel
Tool – End mill 20 mm diameter

3. Data for milling
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
C80 steel 170-200 26 0.3 130 0.3
Select the cutter material and calculate spindle speed and feed.
5
”
1
”
2.5
5 ”
”
4 (4,
” 4)
Program
Zero
4
”
Fig.2
7. Write APT program for the same component (Fig.2) with the same data.
8. Write APT program for the component shown in fig.
(P.N.Rao page 364, Fig.13.43)
Material- C35 steel Tool – End mill φ10 mm
Select the cutter material and calculate spindle speed and feed.
Data for milling
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
C35 steel 120-180 25 0.13 80 0.18

4. 41-60
9. Write manual part program for the component shown in fig.3
Raw material – 3” x 3.5” x ½ “ Aluminium
Tools – 1) End mill 1/4” 2) Drill 1/8”
Data for milling
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
Aluminium 70-105 120 0.28 240 0.25
Data for drilling
Work material Hardness HSS
BHN Speed Feed
m/min mm/rev
Aluminium 70-105 275 0.13-0.90
Fig.3

5. 10. Write manual part program for the component shown in Fig.4.
Tools used – 1) Rough turning (max. depth of cut = 1 mm)
2) Finish turning ( max. depth of cut = 0.5 mm)
Data for turning
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
C 20 steel 110-160 40 0.3 150 0.38
Fig.4
11. Write APT program for the component shown in fig. 5 using PATERN,
MATRIX,TRACUT.
Fig.5
12. For the component shown in fig.6 (thickness = 10 mm), write APT program
Material- C35 steel
Tool – End mill φ20 mm

6. Data for milling
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
C35 steel 120-180 25 0.13 80 0.18
Select the cutter material and calculate spindle speed and feed.
45
15
R15 R10
15
50
50
15
R15 15
45
Fig.6

7. 61-80
13. Write a subroutine for drilling any number of holes along a circle (Fig.7) The
inputs are the following:
# 1 = X coordinate of the center of the circle
# 2 = Y coordinate of the center of the circle
# 3 = Diameter of the circle
# 4 = Total depth through which the hole making operation is to be done
# 5 = Total number of points
# 6 = Actual canned cycle to be used (81,82,84,85,86)
# 8 = Height of the rapid plane in Z coordinate
# 9 = The feed rate to be used
Write statements in the main program to drill and Counterbore holes for the
component shown in fig.7.
Fig.7 Fig.8
14. Write manual part program for the component shown in Fig.8.
Raw material – Diameter 40 mm
Tools used – 1) Facing (T01)
2) Rough turning (T02) - max. depth of cut = 2.5 mm
2) Finish turning (T03) - max. depth of cut = 1 mm
Data for turning
Work material Hardness HSS Carbide
BHN Speed Feed Speed Feed
m/min mm/rev m/min mm/rev
Copper Alloy 120-160 200 0.25 300 0.25
15. Write APT program for machining the step of the component shown in fig. 9.
(Dimensions are in inches)
Tool (1’’ end mill)
Speed – 305 rpm
Feed – 1.2 inch/min

8. 2.0
1.0 1.0
0.2
R 0.4
3.0
2.6
0.2
0.2 0.2
4.0
Program Zero
0.2
1.0
Fig.9
16. Write APT program for machining the component shown in fig. 10.