Siemens Sinumerik 840D sl Programming Manual page 59

Changeover between G41 and G42 in operation with cutter radius compensation
The offset direction (left or right) can be changed over directly without having to leave the
compensation mode.
The new offset direction is approached with the next block, through an axis motion.
Figure 3-13
Deselection of the tool offset
There are two methods of deselecting the tool offset, which can be set through the setting
data 42494 $SC_CUTCOM_ACT_DEACT_CTRL.
1. Method A:
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Changeover of the tool offset direction at block start and end of block
If G40 is programmed in a block without axis motion, the tool radius compensation is
deselected only with the next block through an axis motion.
Motion commands
3.4 Tool offset functions
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