Siemens SINUMERIK 840D sl Programming Manual page 521

Further information
Effectiveness of the modified cutting data
The modified tool nose position and the modified tool nose reference point are immediately
effective when programming, even for a tool that is already active. A tool does not have to be
re-selected for this purpose.
Influence of the active machining plane
To determine modified tool nose position, cutting direction and holder or clearance angle, the
evaluation of the cutting edge in the active plane (G17 - G19) is decisive.
However, if setting data SD42940 $SC_TOOL_LENGTH_CONST (change of the tool length
component when selecting the plane), a valid value not equal to zero (plus or minus 17, 18
or 19), then its contents define the plane in which the relevant quantities are evaluated.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
7.11 Cutting data modification for tools that can be rotated (CUTMOD)
Tool offsets
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