On Sep 26, 10:23*pm, Ignoramus24898

Spot drill if you need to hold +/- .002 location, stub drill maybe +/-
.005, *regular drill maybe +/- .010 or worse. So how accurate
determines answer.

Karl

I will use a spot drill indeed. Full diameter holes with spot drill,
perhaps 1/8" deep, to provide guidance for the regular drill.

i

If I were doing this on a manual mill, I would spot drill with a drill
whose diameter is about the size of the web of the drill used for the
hole.

Dan