HEIDENHAIN TNC 640 (34059x-05) ISO programming - Manual (Page 201)

Tool compensation 5.3
5
TNC 640 | User's ManualDIN/ISO Programming | 1/2015
201
Radius compensation: Machining corners
Outside corners:
If you program radius compensation, the TNC moves the tool
around outside corners on a transitional arc. If necessary, the
TNC reduces the feed rate at outside corners to reduce machine
stress, for example at very great changes of direction.
Inside corners:
The TNC calculates the intersection of the tool center paths at
inside corners under radius compensation. From this point it
then starts the next contour element. This prevents damage
to the workpiece at the inside corners. The permissible tool
radius, therefore, is limited by the geometry of the programmed
contour.
Danger of collision!
To prevent the tool from damaging the contour, be
careful not to program the starting or end position for
machining inside corners at a corner of the contour.