Please Note While Programming - HEIDENHAIN TNC 640 User Manual

Fixed Cycles: Drilling | BACK BORING (Cycle 204, DIN/ISO: G204)

Please note while programming:

Machine and TNC must be specially prepared by the
machine tool builder for use of this cycle.
This cycle is effective only for machines with servo-
controlled spindle.
Special boring bars for upward cutting are required for
this cycle.
Program a positioning block for the starting point (hole
center) in the working plane with radius compensation
R0.
After machining, the TNC positions the tool back at the
starting point of the machining plane. This way, you can
continue positioning incrementally.
The algebraic sign for the cycle parameter depth
determines the working direction. Note: A positive sign
bores in the direction of the positive spindle axis.
Enter the tool length so that the underside of the boring
bar is measured and not the tool tip.
When calculating the starting point for boring, the TNC
considers the tooth length of the boring bar and the
thickness of the material.
If the functions M7 or M8 were active before calling the
cycle, the TNC will reconstruct this previous state at the
end of the cycle.
Danger of collision!
There is a danger of collision if you select the disengaging
direction incorrectly. Any existing mirroring in the work plane is
not taken into account for the disengaging direction. However,
active transformations are considered with disengaging.
Check the position of the tool tip when you program a
spindle orientation to the angle that you enter in Q336 (for
example, in the Positioning with Manual Data Input mode
of operation). No transformations should be active here.
Select the angle so that the tool tip is parallel to the
disengaging direction
Select the disengaging direction Q214 so that the tool moves
away from the edge of the hole
HEIDENHAIN | User's manual for cycle programming | 10/2017
NOTICE
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