Help with drill-Mill conversion

**Ross77** · 14-06-2009

Let me get this right... you're drilling out the quill to allow a draw bar through to pull the ER collet chuck into the quill... so what are you planning to tap? did I miss something?

I decided against drilling all the way through the quill as I could only get a 6mm hole through the splined section and the chuck needs M10, resulting in a long thin drawbar and some sort of thresd adaptor.

Bill suggested drilling from the chuck end up into the quill and then use a bolt through the chuck to secure it (similar to some drill chucks)

So i need to to drill a 7.5mm hole in the quill and then tap it for M8, dose that make sense?

**Robin Hewitt** · 14-06-2009

Can't you just put a fancy nut through the taper knockout slot and save driling anything?

**Ross77** · 15-06-2009

Can't you just put a fancy nut through the taper knockout slot and save driling anything?

with the extra long tap at £7 and probably the same for the correct drill bit. That's looking like a good idea, it's only a 10mm slot tho so M8 tread is pushing it a bit...

Would a M6 be good enough?

Irving
Thanks for the info on inverters. just got one to play with

**Robin Hewitt** · 15-06-2009

M5 even, so long as you use a good quality screw and key. HT would be overkill, just avoid stainless and cheapies.

If you buy a box of screws you could torque one to destruction in a piece of scrap. Then you'd know