In article o.uk,
Dave Liquorice wrote:
I could cut a cross with a Dremel to provide the centre?

If you can do that why not just cut a slot and use a parallel sided
(not wedge shaped) straight screwdriver after the soak with
PlusGas/Diesel? Gentle use of a powered impact driver might be better
than a hand held tool. How much pressure can you apply to stop any
driver turning out without distorting the bit you want to keep?

That's how I broke them off flush in the first place. ;-)

--
*If you try to fail and succeed, which have you done? *

Dave Plowman London SW
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