HEIDENHAIN iTNC 530 (340 422) ISO programming User Manual
Page 257

HEIDENHAIN iTNC 530
257
8.3 Cy
cles f
o
r Dr
illing
, T
a
p
p
ing
and
Th
read Millin
g
U
U
U
U
Set-up clearance
Q200 (incremental value): Distance
between tool tip (at starting position) and workpiece 
surface.
U
U
U
U
Thread depth
Q201 (incremental value): Distance
between workpiece surface and end of thread.
U
U
U
U
Pitch
Q239
Pitch of the thread. The algebraic sign differentiates 
between right-hand and left-hand threads:
+ = right-hand thread
– = left-hand thread
U
U
U
U
Workpiece surface coordinate
Q203 (absolute
value): Coordinate of the workpiece surface.
U
U
U
U
2nd set-up clearance
Q204 (incremental value):
Coordinate in the tool axis at which no collision 
between tool and workpiece (clamping devices) can 
occur.
U
U
U
U
Infeed depth for chip breaking
Q257 (incremental
value): Depth at which TNC carries out chip breaking
U
U
U
U
Retraction rate for chip breaking
Q256: The TNC
multiplies the pitch Q239 by the programmed value 
and retracts the tool by the calculated value during 
chip breaking. If you enter Q256 = 0, the TNC retracts 
the tool completely from the hole (to the set-up 
clearance) for chip release.
U
U
U
U
Angle for spindle orientation
Q336 (absolute
value): Angle at which the TNC positions the tool 
before machining the thread. This allows you to 
regroove the thread, if required.
Retracting after a program interruption
If you interrupt program run during thread cutting with the machine 
stop button, the TNC will display the MANUAL OPERATION soft key. 
If you press the MANUAL OPERATION key, you can retract the tool 
under program control. Simply press the positive axis direction button 
of the active tool axis.
Example: NC blocks
N260 G207 RIGID TAPPING NEW
Q200=2
;SET-UP CLEARANCE
Q201=-20
;DEPTH
Q239=+1
;PITCH
Q203=+25
;SURFACE COORDINATE
Q204=50
;2ND SET-UP CLEARANCE
