Here is the address of the company that makes the special O-Rings for
friction-drive disk tires.  They also supply gears, precision shafting,
chain and belt drives, oil-less bearing bushings, and all sorts of
other goodies in small and medium sizes.  These items would be useful
for anyone building their own roll-drive, spoolbox, or keyframe.

  W. M. Berg, Inc.
  499 Ocean Ave,
  East Rockaway, NY 11518
  Phone 516-599-5010; Fax 516-599-3274

Richard Vance