9 bore milling (cycle 208, din/iso: g208), Cycle run – HEIDENHAIN TNC 320 (340 55x-05) Cycle programming User Manual
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HEIDENHAIN TNC 320
83
3.9 BORE MILLING (Cy
c
le 208, DIN/ISO: G208)
3.9 BORE MILLING (Cycle 208,
DIN/ISO: G208)
Cycle run
1
The TNC positions the tool in the spindle axis at rapid traverse
FMAX to the programmed set-up clearance above the workpiece
surface and then moves the tool to the bore hole circumference on
a rounded arc (if enough space is available).
2
The tool mills in a helix from the current position to the first
plunging depth at the programmed feed rate F.
3
When the drilling depth is reached, the TNC once again traverses
a full circle to remove the material remaining after the initial
plunge.
4
The TNC then positions the tool at the center of the hole again.
5
Finally the TNC returns to the set-up clearance at FMAX. If
programmed, the tool moves to the 2nd set-up clearance at
FMAX.