Hi guys! Been lurking here for years and finally feel like I might have a tip to offer.
I had a bead stuck on a mandrel. I could rotate the bead but it just wouldn't slide off the mandrel, even after trying the freezer trick. So I got out my dremel, and used the sanding disc I use for smoothing my dogs' nails, and ran it around the tip of the mandrel.
TaDah! that reduced the mandrel thickness enough that the bead slid right off.
I hope that is helpful to someone, someday.