HEIDENHAIN TNC 640 (34059x-01) Cycle programming - Manual (Page 360)

360 Cycles: Turning
13.24 CONT
OUR-P
A
RALLEL THREAD (Cy
c
le 830)
Please note while programming:
Program a positioning block to the starting position with
radius compensation R0 before the cycle call.
The approach path (Q465) must be long enough for the
feed axes to be accelerated to the required velocity.
The overrun path (Q466) must be long enough to
decelerate the feed axes.
Both the approach and overrun take place outside the
defined contour.
When the TNC runs a thread cut, the feed-rate override
knob is disabled. The spindle speed override knob is active
only within a limited range, which is defined by the
machine tool builder (refer to your machine manual).
Before calling the cycle you must program the cycle 14
CONTOUR GEOMETRY
to define the subprogram number.