To answer Mr. Gellerman's question yesterday about using modern
materials for the frictional circumference on a 'radial wheel and
plate' variable speed transmission: this has been developed, and is
quite possible.

Such transmissions still have applications in modern equipment.  The
people who make precision gears and transmission parts have such a
product.  It is a large 'O-Ring', made of a specially compounded
polymer designed for frictional contact service.  The O-Ring is
stretched over the circumference of a grooved wheel.

This stuff is amazingly durable.  These rings, in narrower widths, are
also used as transmission belts.  22 years ago I put a solid-state vs.
motor in my Ampico drawer, and used 2 such 1/8" belts as the primary
speed reduction mechanism (no noise).  The original O-Rings haven't
quit yet.

The rings come in all different widths and diameters, and they also
supply the grooved wheels, either with hubs drilled any you want, or as
'hubless plates' that could be attached to the existing slider hub in
place of the leather wheel assembly.  Or they also sell just the
O-Rings; that is the important part.

Unfortunately, the exact firm name and address is at work.  I will post
it on Monday.

Richard Vance