248
PROGRAMMING EXAMPLES
96-8000
June 1999
M98   P3701
G00   Z.1
G100   X0.   Y0. (Cancel mirror image X and Y axes)
G28   G91   Y0   Z0
M30
O3701 (Contour subprogram)
G01   X-.469   Y1.2497
G03   X-.5501   Y1.2967   R.0625
G01   X-1.0804   Y1.12
G03   X-1.12   Y1.0804   R.0625
G01   X-1.2967   Y.5501
G03   X-1.2497   Y.469   R.0625
G01   X-.3658   Y.2923
G03   X-.2923   Y.3658   R.0625
M99
%
THREAD M ILLING
We will use the following example and go through the thread milling procedures step-by-step to get the desired
result:
DATA:
·
I.D. Thread milling a 1.5 x 8 TPI hole.
· Using .750 diameter x 1.0 thread hob.
· Take the hole diameter 1.500. Subtract cutter diameter .750 = .750 Then divide by 2 = .375.
STEP 1:  Within this space we need to turn on cutter compensation and ramp on to the circle to be machined.
STEP 2:  Perform complete circle while simultaneously moving in the Z-axis the amount of one full pitch of the
thread. This is called helical interpolation.
STEP 3:  Ramp off the circle and turn off the cutter compensation.
Note: Always climb cut the cutter.
I.D. will be G03; O.D. will be G02.  An I.D. right hand thread will move up in the Z-axis by the amount of one
thread pitch. An O.D. right hand thread will move down in the Z-axis by the amount of one thread pitch.
PITCH = 1.0/Threads per inch
Example 1.0 divided by 8 TPI = .125