解:选用T1=ф20铣刀、T2=中心钻、T3=ф6中心钻。
O001
G17 G40 G80
N001 G00 G91 G30 X0 Y0 Z0 T1;
M06;
G00 G90 G54 X0 Y0 Z0;
G43 H01 Z20 M13 S1000;
Z-42.;
G01 G42 D01 X-50. F400;
G02 I50.J0.F150;
G00 Y0.;
G40 Z100.;
G00 G90 G54 X-110. Y-100.;
Z-42.;
G01 G41 X-90. F500;
Y82
X-82. Y90.;
X82.;
X82. Y90.;
X-82.;
X82. Y-90.;
X-82.;
G00 Z100.;
G40;
N002 G00 G91 G30 X0 Y0 Z0 T1;
M06;
G00 G90 G54 X-60. Y-60.;
G43 H02 Z10 M03 S2000;
G99 G81 Z-3. R5. F150;
Y60.;
X60.;
Y-60.;
GOO G80 Z100.;
N003 G91 G30 X0 Y0 Z0 T3;
M6;
G00 G90 G54 X-60. Y-60.;
G43 H02 Z10 M03 S2000;
G99 G81 Z-12 R3. F150;
Y60.;
X60. Z-42.;
Y-60.;
GOO G80 Z100.;
G00 G28 Y0;
M30;