Hot tap indicator missing?

[Longshanks]

Hi

See further photos. The screw looks a tad bigger than the 3mm but, rather than t’other way around?

Thanks

 

[Longshanks]

Definitely 3mm tho.

 

[charlie275]

That's a masonry bit so the shank will be smaller.

M3 screw fits a 3mm hole. M4 fits a 4mm hole, etc.

Conversely, 3mm bit won't fit inside a M3 thread, etc.

It's like rocket science only simpler.

 

[Longshanks]

Sorry, didn’t legislate for the differential masonry bit sizes. Just been to B&Q. Looks more like an M4 (my eyes again). Only thing is they’re all 16mm now. Guess I have to search for M4 15mm length?

Gracias

 

[charlie275]

1mm is unlikely to make a difference.

Bolts can be cut down though. Wind up a couple of nuts on the screw, cut or file to desired length, unwind the nuts to remake the thread.

Edit: Btw, the links I posted earlier were for stainless steel, the B&Q ones are not. Just saying.

 

[Longshanks]

Thanks. Seems a bit of a palaver for a screw for a sink no more than 6 years old?