Bench roller for flameworking / lampworking

Bench rollers are invaluable tools for solid or hollow flameworking -- for quickly checking and centering your handles and work in progress. But as a newbie, I got frustrated at the $250+ price tag, so I designed these and immediately started seeing the benefits in my work. Check this video for a good example (using a different roller): https://youtu.be/T7W_gnHKcBc?si=BZYw2y3XtAAHbuph&t=386 You will need standard 8mm x 22mm x 7mm skateboard bearings, M8 / 5/16" bolts/nuts/washers, and a small length of half-inch PVC irrigation pipe to build. The pipe should be a snug fit, so gluing is optional. I'd more recommend that you screw the whole thing to your workbench or to a heavy piece of wood, so that you can use the rollers quickly without having to worry about knocking them over.Due to being made out of plastic, these are not for use right next to your torch or other burner. I print them with polycarbonate for the most heat resistance, which is self-extinguishing and supposedly d