HEIDENHAIN TNC 426, User Manual

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HEIDENHAIN TNC 426, TNC 430 339
8.9 Special Cy
cles
TOLERANCE (Cycle 32)
The TNC automatically smoothens the contour between two path
elements (whether compensated or not). The tool has constant
contact with the workpiece surface. If necessary, the TNC
automatically reduces the programmed feed rate so that the program
can be machined at the fastest possible speed without short pauses
for computing time. As a result the surface quality is improved and the
machine is protected.
A contour deviation results from the smoothing out. The size of this
deviation
(tolerance value) is set in a machine parameter by the
machine manufacturer. You can change the pre-set tolerance value
with Cycle 32.
U
Tolerance value : Permissible contour deviation in
mm
Example: NC blocks
95 CYCL DEF 32.0 TOLERANCE
96 CYCL DEF 32.1 T0.05
Machine and control must be specially prepared by the
machine tool builder for use of this cycle.
Before programming, note the following:
Cycle 32 is DEF active which means that it becomes
effective as soon as it is defined in the part program.
You can reset Cycle 32 by defining it again and confirming
the dialog question after the
tolerance value with NO
ENT. Resetting Cycle 32 reactivates the pre-set tolerance: