Brian Gaff wrote
Martin Brown wrote
robgraham wrote

I know it's not strictly DIY, but I'm tasked with getting them apart !

Two bowls on the same diameter and are well wedged together slightly at an angle. I wonder if they been taken out
of the dishwasher hot by one of the members of the family and have effectively 'shrunk' together, but they certainly
won't come apart.

Any ideas - I've tried hot water and then the deep freeze without
success - maybe significant oven heat ?

You want to apply the thermal shock in the opposite direction. Get them as cold as possible and then submerge the
outer one into near boiling water and pray that as it warms up it will free itself.

The bad news is that Pyrex hardly expands at all which is why it is preferred for telescope mirrors etc. I suspect
the things were
mechanically jammed together and may be less keen about coming apart.

Do you have access to a decompression chamber, maybe you could make the air trapped between them push them apart by
reducing the pressure on the outside?

I doubt there is air trapped between them myself.

They would have to be too perfectly round for that to happen.

I'd try another trip thru the dishwasher first myself.