a Steel Box Section Build with SBR20 & Ballscrews Plus a few questions

[grain_r]

Hey all

Well I though I would pop a couple more pics on here as I'm doing bits to keep me motivated too. I'm having a tapping Issue for some reason at the moment. I have used a 4.2mm Cobalt drill bit and I have used a centre punch and then I have used the cobalt but it wanders I have then even turned the pillar drill by hand a few times and I was surprised but it did cut which I guess is because its a new drill bit and then started it and unfortunately it still wandered so I stopped it and put a little pressure on the work piece and then started the drill and that works better but still not good. I think My holes have then gone oval even when the wandering stops when in a decent start for the bit.

I'm thinking I might even get a better job done with a hand dewalt battery drill. Yes I know its a cheap drill but Would have thought it should drill holes but maybe its me.
I have even tried to use a stepped drill of 4mm and better rigidity but they are the worst with one side ok and the other only 1 thread

The Culprit



The Holes (Although it does screw in and hold when tightened but not right somewhere)



I have ordered a new tapered tap but wondering if the 3mm just isn't thick enough. Luckily On this bit I can put nuts on them but won't be able to weld them on.

Oh Well I will carry on.