linkuk wrote:

"linkuk" wrote in message
...
Any advice for what sort of drills to use for drilling old very tough
concrete. No holes will be less that 6 mm diameter.

I bought some from B&Q that were supposed to be for concrete but they were
a miserable failurs so were probably cheap and nasty ones.

I meant no hole will be GREATER than 10mm.

What sort of power drill are you using?
Do you need one hole, or ten thousand?