Harry Bloomfield wrote:
Cash explained :
GMM wrote:
I need to send a (network, not power!) cable through a door frame.
The plan is to go through the plaster beside the frame (a couple of
inches before an adjoining door), at a bit of an angle to come out
on the edge of the architrave on the other side. The total depth
of this hole will be 200 - 250mm (well, 8 - 10 inches anyway) and
most of it will be through timber.
Soooooo....I was trying to find a drill long enough to get through
that lot. Plenty of masonry jobbies to be had, SDS or not, but
they're not very good on timber. The only things I can find are
extended flat bits (which might be tricky to get going at the angle
I need) and augur bits, which might be fine but really should be in
a brace and a) I haven't got one and b) I couldn't turn a brace in
that position.

Why doesn't anyone sell a standard HSS/spur/multipurpose bit this
kind of length? More importantly, what's the right way to do this?

Cheers

GMM,

You can get 'long series' suitable twist drills from reputable tool
suppliers long enough to do what you want, or you could just grind
the thread off the auger bit and stick it in an electric drill [1]
keeping a fairly heavy pressure on it as you drill the hole. (A
bit brutish, but this trick has often got me out of a bit of bother,
and I now keep a few of the common sizes (that have been adapted
that way) in the toolbox). [1] Just make sure that you get one without
the tapered square on
the end - or if that is not possible, just cut the taper off.

Cash

Not actually tried it, but could an ordinary blunt ended SDS masonry
be used, but with the blunt spear end ground so it would cut into
wood?

Harry,

I've never tried that but I would suspect that it would tear rather than cut
due to the shape of the end. I might grind an old masonry bit over the next
few days and give it a go to see what happens.

As a matter of interest, the Tungsten tip on a new masonry is relatively
'sharp' and may just work given a bit of pushing and a good electric drill.

Cash