I recently picked up a vintage riveted bracelet that needed some serious deep cleaning. My first attempts with an ultrasonic cleaner didn’t so much to loosen the mega-crud build up inside the links. There needed to be another way. A simple google search put me on to a thread some 10 years old on TRF. The advice that shined thru was from @janice&fred : boil the bracelet. Two boilings and rinses and the links are free and clear of gunk. Amazing! Just wanted to use this space to share and say thanks to @janice&fred for the good advice. Although I’ll say...
Yes, it does expand. But boiling it in water will not heat the steel beyond 212 degrees F. The amount of expansion from 70 degrees to 212 degrees isn't a lot for the material plus the vintage bracelet has play. That minimal expansion isn't going to bust anything.
Wish I could say I did but nothing added. Using my crisp, white pot wasn't just for visual effect - the pot is usually stark white. I used it because it's enameled. Thought it would be good to avoid metal-on-metal boiling. Maybe not a big deal.