How do you spot pierce a pilot hole for precise drill locations?

[TomWS]

Minimum hole size in 1/8" aluminum?

I think @Agent86 reference above is a good one and might give you what you need. For my part, I don’t try to cut accurate holes below 5/8", mainly because I don’t have to. In your case, where you’re in production, maybe it’s necessary. In my case, however, what I want is accurately positioned holes and, to do that, I simply burn a mark in the plate using the same CNC system as the rest of the piece. To burn a mark I do all ‘holes’ first and I do these with a 20A nozzle, run the cutter at 15 …