[brinchen]

Wonder how to do a repeat in G81?

Ex:
G81Z-20.R2.F500M51
G91Y-5. ?5
G80

?5= repeat 5 times, but what letter is-?
I dont know if its possible, but i think so.

[Superman]

Wonder how to do a repeat in G81?

Ex:
G81Z-20.R2.F500M51
G91Y-5. ?5
G80

?5= repeat 5 times, but what letter is-?
I dont know if its possible, but i think so.

Yes,
G81 Z-20. R2. F500 M51
G91Y-5.
G91Y-5.
G91Y-5.
G91Y-5.
G91Y-5.

or make a sub-routine ( G71 set an initial plane, M53=return to G71, M54=return to R plane)
Your sub must not have any interpolating g-codes ( G0,G1,G2, or G3)

G0 X0. Y0.
S1000 M3
G43 H1 Z50.
G71 Z10.
M51 ( or M8 )
G81 X0. Y0. Z-20. R2. F500 M53
CALL OHOLE Q5 ( Q=# of repeats )
G80 ( or G00 )( G80 forces spindle stop as well as cycle cancel )
M9
M5
...
M30
()
OHOLE ( PITCH )
G91 Y5. ( move incremental Y 5mm )
G90 ( back to absolute - just to keep it safe )
RTS
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