For (some?) metal platters you can quickly reduce them to a shapeless lump by applying the flame of a standard plumber's gas blowtorch. Haven't tried that with vitreous platters.
My preference - primarily because it's far more fun - is to use an Arc welder. If you're very careful about where you put the ground clamp and where you strike your arc you can have some (very, very brief) fun with the motors too. Occasionally you can get a chip to pop nicely as well, though obviously your main focus should be around the platters :)
Biting the hand that feeds IT
