Okay, got a problem with an outer bearing race left in a blind hole. There has been some suggestion of making two cuts in the race with a Dremel. What cutting tool are people using to do this? The bearing has an OD of 16mm but the smallest cutting off disc I can find is 24mm. Bearing races are pretty tough things so I'm guess most bits are not going to touch it.

maybe use on of their grinders instead – they're pretty small dia and you're less likely to cut into the underlying surface as the cylinder ones will hit the race 'square'

Got to an engineering shop and ask them to remove it with a blind bearing puller – or you might be lucky enough to be able to get an expanding bolt to get enough purchase to grip it

What tyres for a dremel?

Blind bearing puller sounds like the best option.
Failing that, if possible, get a bolt welded head first to the bearing. The heat of the weld will loosen it and the shank of the bolt will give you something to grip to pull on.

cheers guys. Thinking about it, I'm not sure dremel bits would touch a bearing race actually. They're bloody hard (except the inner race that fell to pieces and caused the problem!)

You can cut a bearing race with a dremel but expect to burn some discs.

For working in small spaces, just keep some worn down discs rather than running them til they vanish.

Thinking about it, I'm not sure dremel bits would touch a bearing race actually. They're bloody hard

I've got some diamond discs I reckon would – they eat through the hardened steel of my rollerski pole tips which used to take ages to sharpen with a normal grinding wheel.

Can you access the side of the race? no doubt its about 1/2 mill thick
You may be able to chisel through it
But i think trying to lever it out using a thin blade might be your best option.Masking tape round the middle of the bladed thing should prevent it from marking the surface

I might try levering it out before I go spending more money. It's in the freezer right now with the plan being to pour boiling water over the aluminium bits later tonight and give it a go. Failing that, I was thinking of using the dremel type tool to cut three slots in the internal lip of the frame so I can get behind the race and drift it out.

Same problem I had when I did one recently, was expecting it to be a bitch of a job, but clamped it up with soft jaws in the vice as close as possible to the pivot, did the boiling water trick, and it easily tapped out with a drift from the back held at an angle(not saying yours will be just as easy though, I may have just been lucky).

fingers crossed!