Siemens SINUMERIK 840D Function Manual page 145

Example
Program code
N55 M3 S500 G90 G18
...
N65 MSG ("thread cutting")
MM_THREAD:
N67 $AC_LIFTFAST=0
N68 G0 Z5
N69 X10
N70 G33 Z30 K5 LFON DILF=10 LFWP
ALF=7
N71 G33 Z55 X15
N72 G1
N69 IF $AC_LIFTFAST GOTOB MM_THREAD ; If thread cutting has been
N90 MSG ("")
...
N70 M30
N55 M3 S500 G90 G0 X0 Z0
...
N87 MSG ("tapping")
N88 LFOF
N89 CYCLE...
N90 MSG ("")
...
N99 M30
Behavior at power on and reset
After power on and reset, the following settings are activated:
● Initial settings for the retraction motion (LFON / LFOF) and retraction direction
(LFTXT / LFWP): MD20150 $MC_GCODE_RESET_VALUES
● Retraction path: MD21200 $MC_LIFTFAST_DIST
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
Comment
; Set active machining plane.
; Reset before starting the thread.
; Enable fast retraction for thread
cutting.
; Retraction path = 10 mm
; Retraction plane Z/X (because of G18).
; Retraction direction -X (with ALF=3;
retraction direction +X).
; Deselect thread cutting.
interrupted.
; Deactivate fast retraction before
tapping.
; Tapping cycle with G33.
V1: Feedrates
5.2 Path feedrate F
145