VPI TNT Bearing question

I did something similar to a TNT with a non-inverted bearing by extending the threaded thrust rod outside the bearing well. A massive brass donut threads onto the rod, with an extensible footer that drains vibration into the platform below. One of many modifications to TNT. I'm not a fan of inverted bearings. The non-inverted bearing stays better lubricated and puts bearing noise down below, where the brass coupler can absorb and drain it into the platform. I also replaced the steel ball bearing with a ceramic ball that floats between dual plastic thrust plates. Two points of contact spreads the load for reduced friction and stress at the thrust plate-- allowing for a heavier platter.

Adding mass and coupling to the platform should help an inverted bearing too.

You could also set the platter bearing into Panzerholz and just replace the entire vpi plinth with it and mounting your tone arm and cartridge would benefit substantially also.

Panzerholz is extremely effective at reducing parasitic vibrations that cause distortions.

Yes, the TNT non-inverted Mk5 bearing is a significant upgrade over the previous generations. The older TNT bearings were made out of aluminum and were attached using 3 small bolts. The Mk5 bearing is made out of stainless steel with MUCH greater mass. The bearing is mechanically coupled to the plinth using a very fine threaded 3 inch stainless steel collar which secures the bearing much better than the previous versions. In addition, the Mk5 bearing has much thicker Rulon (sp?) bearing collar sleeves which are made to a higher tolerance.

Some Mk5 bearings do not come with the 3 inch threaded mounting collar but come with a traditional nut and bolt combination, although not as attractive, performance wise they are the same. I own three examples of the TNT bearing. TNT Mk3.5, TNT Mk5 with nut and bolt, and a Mk5 with the 3 inch collar. The end result with the Mk5 bearing is a quieter bearing with improved micro detail and dynamics

VPI no longer stocks the MK5 bearing, therefore finding a bearing will be your challenge. The Mk5 bearing is a drop in replacement for older TNT bearing. The TNT Mk5 inverted, Mk6 and HRX inverted bearing require a larger bearing hole, therefore, older TNT tables will require modification. I am not sure if the new inverted Classic bearing will fit a TNT. Hope this helps