PCB milling with laser - power off when Z is up

I'd be interested to look at that approach Andy ,

ok using M3/M5 is not ideal, however it does work , and i have used it running a 2Kw laser ,
i had more problems with the THC than anything else .. , in the end i prefixed the head height to run 1mm above the plate , as a temp measure , it's still running that way 5 years later

cncbasher wrote: I'd be interested to look at that approach

Well, as I suggested above, I think it would be:

axis.2.motor-pos-cmd => ddt = > abs
abs.is-positive => flipflop.reset
abs.is-negative => flipflop.set

flipflop.out => laser-death-ray