HEIDENHAIN TNC 640 (34059x-02) ISO programming - Manual (Page 191)

Fundamentals of Path Functions 6.2
6
TNC 640 | User's Manual for DIN/ISO Programming | 5/2013
191
Radius compensation
The radius compensation must be in the block in which you
move to the first contour element. You cannot activate radius
compensation in a circle block. Activate it beforehand in a
straight-line block (See "Path contours - Cartesian coordinates",
page 196).
Pre-position
Danger of collision!
Before running a part program, always pre-position
the tool to prevent the possibility of damaging it or
the workpiece.