Universal Drilling (Cycle 203) - HEIDENHAIN TNC 426 B User Manual

Disengaging direction (0/1/2/3/4) Q214: Determine the
direction in which the TNC retracts the tool at the hole
bottom (after spindle orientation).
0: Do not retract tool
1: Retract tool in the negative main axis direction
2: Retract tool in the negative secondary axis direction
3: Retract tool in the positive main axis direction
4: Retract tool in the positive secondary axis direction
Danger of collision!
Check the position of the tool tip when you program a
spindle orientation to 0° (for example, in the Positioning
with Manual Data Input mode of operation). Align the
tool tip so that it is parallel to a coordinate axis. Select a
disengaging direction in which the tool moves away
from the edge of the hole.

UNIVERSAL DRILLING (Cycle 203)

1 The TNC positions the tool in the tool axis at rapid traverse FMAX
to the programmed set-up clearance above the workpiece
surface.
2 The tool drills to the first plunging depth at the programmed feed
rate F .
3 If you have programmed chip breaking, the tool then retracts by
the setup clearance. If you are working without chip breaking, the
tool retracts at the RETRACTION FEED RATE to setup clearance,
remains there — if programmed — for the entered dwell time,
and advances again in FMAX to the setup clearance above the
first PLUNGING DEPTH.
4 The tool then advances with another infeed at the programmed
feed rate. If programmed, the plunging depth is decreased after
each infeed by the decrement.
5 The TNC repeats this process (2 to 4) until the programmed total
hole depth is reached.
6 The tool remains at the hole bottom — if programmed — for the
entered DWELL TIME to cut free, and then retracts to set-up
clearance at the retraction feed rate. If you have entered a 2nd
set-up clearance, the tool subsequently moves to that position in
FMAX.
HEIDENHAIN TNC 426 B, TNC 430
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