I have made a few rings. The two that fit I had made in brass. They perfectly fit. However, the Versatile plastic seems to have shrunk 8 mm going from a 6.25 to a 5.5 ring size! I've checked it about 50 times and trying to figure out why the band came out so shrunk. the inside diameter of the band is definitely 16.700mm =-.02mm. That's a ring size 6.25ish to a 6. So is the Versatile Plastic shrinking that much?