Siemens SINUMERIK 840D sl Programming Manual page 284

Tool radius compensation
10.1 Tool radius compensation (G40, G41, G42, OFFN)
Tool length compensation
The wear parameter assigned to the diameter axis on tool selection can be defined as the
diameter value using an MD. This assignment is not automatically altered when the plane is
subsequently changed. To do this, the tool must be selected again after the plane has been
changed.
Turning:
NORM and KONT can be used to define the tool path on activation and deactivation of
compensation mode (see "Contour approach and retraction (NORM, KONT, KONTC,
KONTT) [Page 287]").
Point of intersection
The intersection point is selected in the setting data:
SD42496 $SC_CUTCOM_CLSD_CONT (response of tool radius compensation with closed
contour)
Value
FALSE
TRUE
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Significance
If two intersections appear on the inside when offsetting an (virtually) closed contour,
which consists of two circle blocks following on from one another, or from one circle
block and one linear block, the intersection positioned closest to the end of block on
the first partial contour is selected, in accordance with standard procedure.
A contour is deemed to be (virtually) closed if the distance between the starting point
of the first block and the end point of the second block is less than 10% of the effective
compensation radius, but not more than 1,000 path increments (corresponds to 1 mm
with 3 decimal places).
In the same situation as described above, the intersection positioned on the first
partial contour closer to the block start is selected.
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
Fundamentals