In article ,
JohnM wrote:
When drilling thin stock, it's hard to beat a step drill. Makes a
rounder hole (more round?) and is far less likely to snatch the
material.

Better still to use a Q-Max type punch. Although IIRC 3 mm steel might be
a bit much.

--
He who laughs last, thinks slowest.

Dave Plowman London SW 12
RIP Acorn