VPI Rim Drive vibrations


I have VPI SSM with RIM drive and SDS. The issue I'm having is a vibration being transferred from rim to the desk/platter. As the result tonarm wobbles a little bit in azimuth plane.
I tried to replace the brownish rim belt, change contact force/distance between the drive and the platter, and reinstall the belt - the vibration still there (exactly one wobble per rim's full revolution - 360 degrees).

The speed stability is very good though - have checked it with KAB Speed Strobe.

Any ideas how to resolve the issue?

Thanks a lot!
krell303
Krell303

I went through a similar issue converting my TNT HR5 to a rim drive. My problem was with pitch variations. I ended up replacing the air bladder feet with large brass cones and setting the rim drive pod on a sorbathane/acrylic bed and steel cones. This has made a vast improvement but requires some intermitent tweaking to keep the pitch steady. When it's on - the rim drive totally beats the belt. I'm in Central Jersey if you ever want to compare notes.

Andy
Anyone compare a silk (or any) thread to the rubber belt and then the Rim Drive. Would love to hear some in-depth analysis.
What would be the bigger improvement.....spending for a Rim Drive or taking the cost and putting it into upgrading from an older Phonomena to a more costly (by that amount) phono section?? Thoughts?
Here is something I just did which further improved my VPI Super Scoutmaster Ref. rimdrive's performance. I placed a round Symposium Acoustics coupler made of aircraft aluminum between the rubber feet on the SAMA- 1 front and 1 rear, which sits on a Symposium Acoustics Ultra Shelf. The sound further improved with more solid presentation, better staging, more stable.