[dave]

Sometimes pilot holes can be the killer, the drill bits in too hard and gags on the swarf, so you back opff and then it just tries to polish if the cutting edge.

Tinks.
I drill all the holes with an air drill and these things drill at least as fast if not much faster than any electric drill without problems, this is not to say that my staff are as sucessfull with drill bits, they don't have to pay for them.

Try to get hold of Dormer drill bits, these are much better than the plastercine ones that are available from B&Q


A good tip:-
If the drill bit starts to squeak then stop drilling straight away. This is happening because the cutting edge has now gone and two pieces of flat metal are rubbing against each other (Drill bit and work piece), All that will happen if you keep drilling is that you will turn the drill bit into a metal cotton bud that will be so soft it will never drill again even if sharpened.:thumb: