HEIDENHAIN SW 68894x-02 - Manual (Page 271)

HEIDENHAIN CNC PILOT 640 271
4.6
Thr
ead
and
under
cut
cy
cles
Recut (longitudinal) thread—expanded
Call the thread-cutting menu
Select thread cycle
Press the Expanded soft key
Press the Recut soft key
 On: Internal thread
 Off: External thread
This optional cycle recuts a single or multi-start external or internal
thread. Since you have already unclamped the workpiece, the CNC
PILOT needs to know the exact position of the thread. Place the
cutting tip of the tap drill in the center of a groove and transfer the
positions to the parameters measured angles and measured position
by pressing the Take over position soft key. From these values the
cycle then calculates the angle of the spindle at the starting point.
This function is available only in manual operation.
Cycle parameters
X1
Starting point of thread
Z2 End point of thread
F1 Thread pitch (= feed rate)
D No. of gears (threads per unit)
U Thread depth – No input:
 External thread: U=0.6134*F1
 Internal thread: U=–0.5413*F1
I Maximum infeed
 I
Reduction of cutting depth
 I=U: One cut
 No input: Calculation from U and F1
GK Run-out length
C Measured angle
ZC Measured position
A Approach (infeed) angle (range: –60° < A < 60°;
default 30°)
 A<0: Infeed on left thread flank
 A>0: Infeed on right thread flank