Siemens SINUMERIK 840D sl Programming Manual page 251

Examples
Example 1: Double cylinder thread with 180° starting point offset
Program code
N10 G1 G54 X99 Z10 S500 F100 M3
N20 G33 Z-100 K4
N30 G0 X102
N40 G0 Z10
N50 G1 X99
N60 G33 Z-100 K4 SF=180
N70 G0 X110
N80 G0 Z10
N90 M30
Fundamentals
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
9.10 Thread cutting with constant lead (G33)
Comment
; Work offset, approach starting point,
activate spindle.
; Cylinder thread: end point in Z
; Retraction to starting position.
; 2. 2nd cut: Starting point offset 180°
; Retract tool.
; End of program.
Motion commands
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