2020 update : JC Verdier La Platine

@xdr Greatly appreciate your responses. It’s great to visualize through photos of your system the SOTA / Roadrunner in action. I see a belt drive, but it can be switched to a thread drive, correct?

You have a lovely system / room, with lots of French stuff unknown to me...... except, of course, the French TT. I especially like your spartan listening chair. I have a Garbriele Mucchi’s Genni chair myself.

@lohanimal Yes, speed still drifts. Some days when the gods, temperature and humidity aligns, I get a few sides of records with speed spot on. I am, however,  enjoying music.

Graham Tricker will be on my list of people to query. I somehow remember that he used to carry JC verdier TT’s. And he dropped the brand when he took on TW  Acustic, implying that La Platine was not comparable to the German tables. 

I look forward to your DD table project.

@ledoux : I confirm you can use the motor both with belt and thread. I tried both and linen is far better than Silk or kevlar.

Albert, from your most recent posts, one would think you would have been better off with one of the German tables. 8^0

This post comments addresses ......BBB

Ball, Bearing and Battery
**********************************

The Ball

Lewm
Not having owned a Verdier, I have no idea what the steel ball does; it sounds like it adds to or is integral to the mechanism of the brake.

@lewm  et al

It has nothing to do with braking, it is not integral to anything on a normal La Platine, but is integral..... to knockoff La Platines.

Platine "knockoffs" exist. They use bad magnets which by themselves are not stable. The ball was introduced to make the magnets stable. This is well known to long term La Platine owners. Mr. Verdier had no choice but to try to help these knockoff (pirate) manufacturers, since the questions, inquiries, concerns from people who purchased these knockoff turntables, were being directed to his company.

His website makes this clear and is I believe self explanatory .

I noticed that many of my Platine Verdier's pirates had a problem with the magnetic system.
Generally the repulsion force is not adequate and it is necessary to complete it with a ball spindle or any other samarium cobalt magnets on the top of the axel. That situation is boring because some of the customers turn away ignorant, they are facing copies and believing that the device is defective, bad designed or bad developed
To give a cure, I am going to indicate my pirates how to build magnetic circuits. The problem is that they use an ordinary steel high carbon tenor.
On magnetic point of view that metal is certainly provided with a weak "coercitive field", but too much important, which decreases the field provided by the magnets. The answer consists in using a magnetic alloy of suitable quality, for example TELAR 57 of ARMCO. when the tooling of the part is over, you have to realize a double fire under vacuum to eliminate the last carbon traces.
And then, to finish, you can paint. the magnetic circuits or realize a surface processing as "zincage bichromatage" which gives that lovely gilded colour. of course that is really more expensive and complicated than ordinary scrap-iron, but now you don't have any excuse.
Good luck pirates
J.C. Verdier

*****************************

Bearing

Xdr et al

As this is a resonance, vibration, hobby trying to generate a tiny signal, a large part of a Turntable and Tonearm "DNA" comes from the type of bearing used in both. I have owned / own turntables and tonearms with very different bearing systems.

Nouvelle Platine and La Platine play in different leagues. Different bearings.

**********************

Battery

As far as the battery discussions go, I did speak with Verdier about this and looked into it in depth. My personal experience is this.

If one lives on a city grid, a condo, highrise, high density type of environment, etc... your power is compromised. This is fact.
Go ahead and try the battery if you desire. I will say the biggest improvement to my system kits, all of them, came when I moved to the country with clean, low density power. It was a night and day difference.

I don't own an electric car, yet, but all my cars and boats depend on good batteries for starting and trolling. Make sure the proper battery is chosen if you choose this project. Drain a starting battery just one time, it becomes compromised with a shorter life. Drain it twice and it is toast. The proper batteries "deep cycle" for this project in my neck of the woods start at $250.
  
fwiw
In the early stages of La Platine ownership and while in "Audiophilia Nervosa" phase ...8^0......I actually explored using my Technics SP10MK11 Platter/motor to drive La Platine.

My conclusion...this has possibilities with "dumb" free spinning platters. Most turntables. Not a good idea with a smart platter system, such as La Platine's, that includes braking. 
 
Stay Safe, Social Distance, Stay healthy.

The undisputed aspect with the La Platine is the magnetic bearing, allowing the platter to rotate while being decoupled. The idea was what attracted me. Having acquired it, it is the execution of the idea that truly intrigued. The metallurgy and the assembly involved are its distinguishing qualities. 

The drive system was the second aspect that required study. Through informed opinions by members of this forum and experimentation, I have come to the following conclusion: the drive material with the least surface area is the best. This translate to the least amount of friction produced by the drive material. And this preserves the inherent braking action of the platter to counteract stylus drag. Thread drive therefore is the best.  Of the threads used, pure silk from YLI was the best, the stock linen ( ? ) thread the least preferred. The silk thread produced a more 'continuous' soundstage with more 'air ' around instruments.

The motor is presently the most troubling aspect. And it has to do with speed stability. I performed a test suggested by @ct0517 observing the number of rotations before the platter comes to a complete stop by firstly turning off the motor and secondly by cutting the thread while still running. This test confirms that the platter is not in a state of free, un-restraint rotation. A braking action is designed into the platter shaft assembly to counteract stylus drag. I then performed the same test, but this time with a high torque Jasmine motor. The results are very similar. This tells me that  a change in motor would not disturb the inherent braking action of the platter. I believe if one were to change a motor system for the La Platine, it has to be compatible with the thread drive. The spindle head of the stock Philips, low torque, motor is coming into contact with the same thread as on the platter side. While the low friction on the platter works to preserve the braking action, the same low friction on the spindle head does not work to preserve speed stability. The stock motor has a different setting for thread and belt drive. The original motor design acknowledges that different material drive with require a different electronic control. And I feel it is the electrics of the motor assembly that is at fault for speed instability. I somehow think that a motor with a servo system works best. But in the thread drive ultra-high end Japanese CS Port Lft1 turntable, it specifically uses a high torque non-servo motor. On the motor front, I am still researching. However, this in no way affect my admiration for the TT and my enjoyment of music produced through it.

There is one other aspect that I have read very little about: the plinth. I have the black MDF plinth. I would like to know more about the Granito plinth. Somehow the combination of concrete, raisin, and stone chips doesn't seem to be a good resonance damper. I would like to be enlightened. 

Interesting read. I have a Transrotor Apollon with 80MM platter and Transrotor Magnetic Drive (TMD) drive assembly. The spindle bearing is some viscous oil fluid, and the platter is spun by three servo controlled motors with belts. Speed drift is a constant with be,FS when they start wearing, but otherwise, it is a stable platform and very robust. Prior to the TMD my platter would spin until it lost rotational inertia. Now, with TMD, it slows down after a few rotations before coming to a complete stop. That is due entirely because of the TMD. Is the braking you speak of on the motors happening during music playback, or only when spinning up or down?