Ray,
Please enlighten me a little more about this...
The G83 (deep hole peck cycle) and G73 (high speed peck cycle) seem to work similarly in milling where Q is concerned. That's why I don't understand. I have always used very shallow pecks when the hole must be very accurate. The last peck is shortened to accommodate the total depth as in: N8 G73 G99 R-0.4315 Z-0.7463 F3.0 Q0.0150 X0.0000 Y0.3937 - the last peck (Q) is .0148". The difference as I see it for the use of G83 over G73 is the retract amount and that is also determined by the chip formed by the material being drilled - such as steel and a long curl chip can use G73 since the chip will extract itself so the retract does not need to totally exit the hole as with G83.
Or have I missed your question totally...?
Thanks,
Bill C.
AFAIK, the *only* difference between G73 and G83 is how far it retracts between pecks - G73 retracts fully to the R plane, while G83 only retracts a small amount from the previous depth. Neither does any of the optimization required for drilling deep holes - reducing RPM, feedrate, and peck depth as the hole goes beyond about 3 diameters deep. That is what I'm after, and seem to have achieved. G73 and G83 also require manually programming the proper peck depth, or programming multiple cycles, to get a clean bottom-side on thru-holes by having the next-to-last peck break partway through the bottom surface, then doing a final peck, with dwell, to finish the hole without a burr on the exit side. Mine now does that automatically, by adjusting the final, and next-to-final peck depths as required.
Regards,
Ray L.