Apologies if this has been done already but I read about it and just tried it and it really works! Mine were sadly very dirty with grease etc. You wrap them in tin foil, lay them in the bath or if your sink is big enough, lay one dishwasher tablet in the bath and cover with very hot water. Leave for over an hour, when you unwrap, the dirt should just wipe off, let me know if you try it. The picture was just after I unwrapped them.
Oh dear @davidevans0000 Please let us know if it works, apparently it is something to do with a reaction to the tin foil? 🤗
this says three hours