Helen- Well done on your weight loss. It’s no easy task to try and
defeat evolutionary hard wired biological desires.
I have used any number if different ring stretchers/ shrinkers. They
all work fine but only on rings with no stones.
When ever you increase or decrease the size of a ring set with
stones, especially something like an eternity band where the stones
are set into the band itself, the stones will either pop out or break
depending on whether or not you are going up or down. Often with
channel set rings we have to leave them oval after sizing because we
don’t want to shift the stone seats.
You’ll just have to size them with a torch.
A note on band shrinking with a stretching/reducing tool. If the
band has a decorative finish like say millgrain, florentine finish,
or engraving, I take a small plastic zip lock bag, one of the
millions that seem to reproduce over night in our shop, and line the
receiving die with it. Then I put the band in. The plastic baggie
gets trashed, but not the ring finish.
Have fun and make lot of jewelry.