Paul,

  I found a good paper on traction drives (34MB) complete with
  illustration. It is interesting to note the researchers references to
  the bearing like attributes of the device and the need for similar
  alloys, hardness and tolerances.

  http://www.grc.nasa.gov/WWW/StructuresMaterials/TribMech/research/A_gear_high_speed.html


  Regards


 BTW I notice they mentioned 15,000 feet per minute pitch line velocity
 which is a lot faster than I could find previously. Encouraging for
 a simple turbo charger based turbo compound engine.


 Paul Lamar


Try this link : http://gltrs.grc.nasa.gov/reports/1985/RP-1154.pdf

Randolph

Yes that goes right to the heart of the matter.

Here is a screen capture of a chart of traction fluids.
Very helpful for our purposes.

Randolph,  here is some hardware we had built a awhile back
before you were on the list.

Also Doug Fir in Japan has a Rotrex traction drive super charger
he is experimenting with.

Paul Lamar