Looking at diamond drill sizes they are 38mm and 52mm, so logically you
use a 52mm core drill for 40mm waste.

Just double checking as it seems like a lot of over size.

Presumably it makes it easier if the hole is slightly off centre.

This question related to the Ikea thread because the current fitting
slopes slightly up hill through the wall yet there is scope to drill a
hole several bricks lower.

All my drill bits and core drills are hundreds of miles away. No room in
the car and I had no idea I would be tackling anything this complex.

Sigh.


Dave R


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