I'm rebuilding some old rolling library ladders. They have 5" diameter metal wheel hubs, about 5/8" thick. They used some sort of glued-on black rubber material for tires, now largely disintegrated. I thought I'd order some 5/8" o-ring cord from McMaster, but they claim that all their various o-ring cords would leave marks on hardwood floors. Kind of like "black heel marks" from some kinds of boot soles, right?
The metal hubs have a couple circumferential grooves on their OD's, but it's just to glue on the original solid rubber they used; it's not like a rim bead on a pneumatic hub. Mechanically, 5/8" diameter Buna- N o-ring would have been a win, but leaving marks all over the floors would be bad.
Any ideas on a substitute material? Or, does anyone know how some boot manufacturers make the sole so it doesn't leave black heel marks on the floor?
Not a huge metal content here, but the hubs are metal, and o-ring's often seal metal.....
Thanks very much for the help!
Dave