Drilling a 13mm hole in ceramic tile with a 10mm drill bit?

[p.thorn]

I need to drill a 13mm hole in a ceramic tile to fix a bathroom basin to the wall. The largest size of tile drill bit sold by the High St sheds is 10mm. What's the best way to proceed? Keep using the 10mm bit to make the hole large enough or start with a clean 10mm hole and then use a larger masonry/steel drill bit to finish off? Tests on a spare piece of tile show the first approach giving a hole not quite round while the second approach gives a round hole with ragged edges.

[Sean Delere]

13mm Tile bits are available.

Try

[Grunff]

Buy a 13mm masonry drill bit.

No.

Drill a small pilot hole, 4-5mm will do, to a depth of only a few mm. Now use a 13mm drill bit to drill your hole.

[Dave]

I bought an adjustable hole cutter for tiles from Tiles'r'Us - can't remember what they're called. A centre drill with an adjustable arm - hole size can be set from about 12mm (guess) to about 40mm (another guess).

Dave

[bill]

Use 13mm masonry in slow drill if you have. Take it slow.Perfect hole will result.

[Guy King]

The message from bill contains these words:

Add water. It retains the dust and makes a sort of grinding paste that helps the bit go through better.

[PM]

And switch off the hammer action :-0

[p.thorn]

as this is a one-off job (hopefully a once-in-a-lifetime job) I did try with just a 13mm masonry drill and I got good results.