Thread cutting (cycle g86, not tnc 410), G86 thread cutting (not tnc 410) – HEIDENHAIN TNC 410 ISO Programming User Manual
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HEIDENHAIN TNC 410, TNC 426, TNC 430
205
8.3 Cy
cles f
o
r Dr
illing
, T
a
p
p
ing
and
Th
read Millin
g
THREAD CUTTING (Cycle G86, not TNC 410)
Cycle G86 THREAD CUTTING is performed by means of spindle
control. The tool moves with the active spindle speed from its current
position to the entered depth. As soon as it reaches the end of thread,
spindle rotation is stopped. Tool approach and departure must be
programmed separately. The most convenient way to do this is by
using OEM cycles. The machine tool builder can give you further
information.
U
U
U
U
Total hole depth
1
: Distance between current tool
position and end of thread
The algebraic sign for the total hole depth determines
the working direction (a negative value means a
negative working direction in the tool axis)
U
U
U
U
Pitch
2
:
Pitch of the thread. The algebraic sign differentiates
between right-hand and left-hand threads:
+= right-hand thread (M3 with negative depth)
– = left-hand thread (M4 with negative depth)
Example: NC block
N22 G86 P01 -20 P02 +1 *
X
Z
11
12
Machine and control must be specially prepared by the
machine tool builder for use of this cycle.
Before programming, note the following:
The TNC calculates the feed rate from the spindle speed.
If the spindle speed override is used during thread cutting,
the feed rate is automatically adjusted.
The feed-rate override knob is disabled.
The TNC automatically activates and deactivates spindle
rotation. Do not program M3 or M4 before cycle call.