On 18 May 2004 04:53:25 -0700, (MBQ) wrote:

T i m wrote in message . ..
Hi folks,

I'm trying to make a special drill for drilling out the stump of a 9"
sq wooden gate post but want to leave the surrounding concrete intact.

The idea is to drill enough 'joined' holes across it to be able to
pull the two chunks out using screw eyes (chain and coachbolt) on some
scaffold pipe, car jack etc (Ideas from this list and thanks g)

So, I bought a cheap (1 pound. market) SDS 14mm drill that I can use
for the SDS part, drill / mig that into some tube (or bar counter
bored on the lathe) and then connected to a large (25mm) wood / steel
drill bit? (cheap from a boot sale?).

But, because it would be difficult to hold the business end of a drill
in the lathe to turn the shank down (or counter bore) for my extension
tube / rod system I think I need to find something big but with a
small shank ready to go ..?

I nearly bought a cheap (39 quid?) set of such drills recently, going
from about 12mm up to 30mm or so but all with 12mm plain shanks but I
wouldn't want to risk ruining such a bit (and the set) on this job?

So, any ideas please? (links prices etc?)


Another thought. How about a "scary sharp" SDS chisel bit?

Hmmm ,, where's the angle grinder .. ;-)

I was 'hoping' for something less energetic. ;-)

The 'problem' with this job is that for a large part of it I'll be
working in a 9" square concrete hole and hence the need to try to get
away from the ground a bit (excuse the pun).

Off to B&Q to check out some electric drill speed augers ..

T i m