Thanks man. House was extensively rennovated last year so it's a brand new new L-shaped concrete lintel supporting the (yes, Victorian) brick chimney. Am just hoping there's no steel in it. The base of the lintel is 70mm thick and i'm drilling a 12mm hole centered 36mm up from the bottom edge.
Give your drill a chance and start with a 6mm bit, then 8, 10, 12.
Much less chance of the drill bit wandering,
and,
you have much more chance of the hole being level & square.
Thanks man. House was extensively rennovated last year so it's a brand new new L-shaped concrete lintel supporting the (yes, Victorian) brick chimney. Am just hoping there's no steel in it. The base of the lintel is 70mm thick and i'm drilling a 12mm hole centered 36mm up from the bottom edge.