For those of us who do not use the ball, the clearance between the two magnets is about 10-11mm.
I have tried Colton thread to terrible effects. The ones I used were almost wool threads. Both the viscose and silk threads are good. @dover mentioned the Eclipse motor system from SOTA. I wrote to Donna @ SOTA, and she confirmed that the motor works with thread drive. A previous poster from France with a Nouvelle La Platine used the SOTA motor. As SOTAs are suspension type TT, the Eclipse may be a good alternate.
On the other hand, Thom from Galibier has developed a motor for his own design as well as for Verdier. Though he is adamant that his motor only works for non-suspended TT. He recommends defeating the suspension on the La Platine, and use Kapton flat belts. His motors have been used on La Platine. As opposed to the SOTA motor which employs a feedback loop, The Roadrunner, the Galibier runs ‘nude’, so to speak.
Your enthusiasm for the La Platine is quite infectious. I have taken more relaxed attitude towards the La Platine, preferring to just enjoy the music it produces. But you have force me to maybe take up a few projects on the La Platine to further enhance its abilities.
BTW, I have had problems with signing onto Audiogon, so I changed my user name.