RE: Drilling wide holes in masonary.

["James Hoye" <james.hoye@xxxxxxx>]

> How do those things work James? Do they just attatch to the dril in
the
> normal way? How do they differ from normal masonary bits, other
> than being
> wider?

Although they are wider, the centres are hollow so there is less drill bit
in contact with the masonary.  This results in considerably less drag on
the
drill, meaning that larger holes can be drilled.  Drills usually specify
(on
the side) the maximum diameters for various materials.

You also need an arbour which fits into the centre of the drill bit - this
goes into your drill chuck and the other part attaches to this.  You would
usually drill a 7mm pilot hole first.  Provided you drill a small amount at
a time, you should be able to manage with a normal drill.  Don't do too
much
or you will overheat it and wreck the bearings.

Also, one arbour will usually fit most of the different size bits, meaning
you only need to buy one of these.

I'll take a picture this evening of a monster bit I've borrowed (110mm) and
send it to the files area and yourself.

James H