Hi all

Having a bit of a nerve wracking time at the moment, hoping someone out there is equipped to say "you idiot, all you need to do is XYZ"

I have a 3/16" (4.76mm) OD x 0.9mm wall thickness tube of 316 stainless mounted in my 4th axis and need to drill a pattern of holes in it. Ideally Ø0.3mm. FSWizard tells me a feed rate of 30mm/min and 15000 or so RPM is appropriate with my little HSS PCB drills (stubby with 1/8" shanks).

I slowed it down to half that plunge rate and attempted a G01 F15 Z0 move and, can't say I was surprised, watched as the bit bent a little and snapped.

The drill point is centred over the A/X axis in the Y direction (A running along X) but I can't honestly say I can even see a spot where it tried to start the hole on the surface of the tube.

Any words of wisdom on a better way to do this before I roll the dice on my last spare 0.3mm bit?

Thanks in anticipation...