Siemens SINUMERIK 828D Function Manual page 1383

Note
The extension for programming the plane of the retraction movement can be used
independently of thread cutting.
Retraction speed
Retraction is performed at maximum axis velocity.
This can be configured in machine data:
MD32000 MAX_AX_VELO.
Retraction acceleration, jerk
Acceleration is performed at maximum possible values.
This can be configured in machine data:
MD32300 MAX_AX_ACCEL.
Example
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
N90 MSG ("")
...
N70 M30
N55 M3 S500 G90 G0 X0 Z0
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
; Set active machining plane
; Reset before beginning of thread
; Enable fast retraction for
thread cutting
; Retraction path = 10 mm
; Retraction plane Z/X
(due to G18)
; Retraction direction -X
(with ALF=3; retraction
direction +X)
; Deactivate thread cutting
; If thread cutting
; was aborted
V1: Feedrates
17.2 Path feedrate F
1383