Simple External Thread Milling

This code is shared for educational purposes only. Use it at your own risk — you are fully responsible for any results.

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(    SIMPLE EXTERNAL THREAD MILLING     )
(   More CNC programs on my website     )
(         RobertKsiazek.com             )
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(PARAMETERS)
XX = 0 (X BOSS POSITION)
YY = 0 (Y BOSS POSITION)
ZZ = 0 (Z START POSITION)
XSAF = 25 (SAFE X POSITION)
ZSAF = 2 (SAFE Z POSITION)
SFEE = 1000 (LEAD IN FEED)
FEED = 1000 (CUTTING FEED SPEED)
VC1 = 20.75 (START MILLING THREAD AT X POSITION)
VC2 = 3 (THREAD PITCH)
VC3 = 10 (REPEAT PITCH)
VC8 = 0 (COUNTER)
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(MACHINE SETUP)
G15 H3 (WORK ZERO NUMBER 3)
G11 X XX Y YY
G17
G90
T1 M6
G56 HA
Z9999
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(MACHINE START)
S5000 M3
M8 (COOLANT ON)
X XSAF Y0
Z ZSAF
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(THREAD MILLING)
Z ZZ (GO TO START Z POSITION)
VC8 = 0 (RESET COUNTER)
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(MAIN LOOP)
N100 (TOP -> DOWN)
VC8 = VC8 + 1 (COUNTER UPDATE)
G1 X VC1 F SFEE (FEED IN)
VC4 = VRCOZ - VMOFZ - VZOFZ[VACOD] - VTOFH[VATOL] (CURRENT Z POSITION)
VC5 = VC4 - VC3 (CALCULATE TARGET Z POSITION)
G1 X VC1 Y0 Z VC% I -VC1 J0 F FEED (FULL ONE THREAD PASS)
IF [VC8 LT VC6] N100 (LOOP)
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(PROGRAM END)
N9999
G1 X XSAF F FEED (BACK OFF)
G10
M5
G0 Z9999
M2
M30
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