I have a ceramic knob...

[Grimly Curmudgeon]

... to fit on a crockery plate that's the right size for my slow cooker. Any suggestions for drilling? Lube, etc? Paraffin, oil, water? I have a set of cobalt-tipped drills but don't want to attack it with totally the wrong tool, iyswim. No great loss if I do crack it, as the plates are plentiful and cost a quid each, but I'd prefer to get it right first time. No way can I use my usual technique of drilling tiles, as that involves punching a start point...

[dom]

Have you considered an epoxy specifically designed for ceramic repair such as Hxtal or Araldite 2020?

[Tabby]

A tile drill is the thing to use. Its not really necessary to punch a starting point, just put tape down, fire up the drill and go in. Do support the ceramic /very/ firmly behind.

NT

[Ret.]

Yes - that's how I would do it. Tile drills 'start' very efficiently and, once through the glaze, the job is as good as done.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember " [e-mail]" saying something like:

I thought of Araldite, but then recalled mention of it going soft with heat. Otoh, even if the grade you mention is heatproof, it's probably not worthwhile acquiring some for one tiny job (and finding a specific grade out here in the sticks will take some doing). A hole will do...

[The Medway Handyman]

Bosch Multi material Drill Bit.

[Nightjar]

Only some grades, including the one usually sold in retail outlets. There are grades that need elevated temperatures to set properly.

Almost certainly true.

Colin Bignell

[Dave Plowman (News)]

Are you certain they'll stand steam?

[Dave Plowman (News)]

I use a glass cutter to provide a centre. Or ticky tape.

[Tabby]

I once got some high temp epoxy, naively thinking it meant what it said. I think it was rated to about 120C. It turned to gloop at boiling point, it was completely useless.

NT

[John Rumm]

Probably where I would start. However be aware some porcelain is *very very* hard, and the only realistic way of cutting it is with something abrasive. Copper rod in a drill press with some aggregate will do it slowly.

[Dave Plowman (News)]

There are tile drills for porcelain. A sort of diamond coated tube with a slot across it. Only thing that works on them.

[Ian & Hilda Dedic]

Have you considered one of those plate thingies that are part of a 2 tier cake stand? they usually have a hole through the middle already for the centre post.... Car boot sale anyone?

dedics

[dennis]

I was drilling holes in mugs a few days ago. The Bosch multi-material drills go through the glaze and the ceramic with ease and no need to crack the glaze first. A bit of tape helps to stop the drill wandering. Don't use hammer.

[John Rumm]

Yup, the mini holesaw style are supposed to be ok.

I also tried a solid carbide one once. Needs active water cooling, lots of pressure (250N) and slowish speeds (700 - 900 rpm). Works sort of - can take 10-15 mins per hole, and you only get 20 holes from a bit at probably £20 - £30 for the bit!

[Gib Bogle]

For really hot chicks?

[Dave Plowman (News)]

They are. Slow but certain.

Holesaw type takes a few minutes - and needs water to cool it - but lasts quite well. Certainly rather more than 20 holes.

[Chris Hogg]

Don't know about the drill type, but plates come in broadly two categories: earthenware, fairly soft and porous and easy to cut or drill, like wall tiles, and vitreous ware, such as porcelain, bone china etc. The latter are generally much harder and more difficult to cut or drill, rather like vitreous tiles or even glass. They also tend to be more expensive......

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Chris Hogg saying something like:

This is just a cheapy, so I expect it's glazed earthenware or similar. Happily, on my visit to Aldi this morning I spotted sets of glass drills, so will have a go at it later on.

[The Other Mike]

Araldite 2020 is completely usuitable for anything other than display purposes, it will rapidly fail with sustained temperatures above 40 deg C

Aralidite 2014 would be a better choice..