Hi Keith, I've just had exactly the same problem. I already have one of these and was going to use it to fit the Screwfix "Fluidmaster" siphon valve and button part no 51173 the button with this unit has a spacer which allows you to surface rather than flush mount the button down to a 19mm hole so it's a no damage risk solution. But if you want to go down the drilling route, when I used this bit to fit some taps to a ceramic kitchen sink, it worked but took an age to break thru the glaze and the "rub" it's way thru the ceramic. Diamond bits are better but very expensive.
Answered by: Screerun
Date published: 2020-07-16