Using the VPI threaded clamp and azimuth change


I am using the VPI threaded delrin clamp that came with my classic 1. It is stated that the threaded clamp is to be used in conjunction with the rubber spindle washer. When it is used this way, it seems like it would negatively affect the azimuth setting. When you screw down the clamp and tighten it against the rubber washer, it does force the outer edge of the LP downward to touch the platter. This causes the LP to have a slight downward dish appearance. When I have set my azimuth on a level surface, does this not cause the azimuth to be out of alignment? Do I need to set my azimuth canted a bit to the outside of the platter to compensate for this effect? How are you VPI users adjusting for this?
andyprice44
It seems impossible to keep the record flat with the washer underneath. The washer holds the LP 1/8" above the platter so, the only way that the LP can make contact with the platter on the outer edges is to dish the LP slightly downward. In my situation the playing surface is always dished downward even if you only lightly tighten the clamp. The playing surface always has a slight rise towards the spindle. I have tried using the clamp without the washer underneath. Due to the built in recess in the classic aluminum platter, this causes the record to dish upward. It only makes sense to me that I need to keep the record surface as flat as possible. I suppose I need to re-adjust my azimuth to account for the dish effect of the VPI clamp system.
Andy, The material of the washer is not critical. You can obtain the correct height by purchasing brass shim stock at a hobby store.

The packs come with a variety of thickness and can be cut with stainless steel scissors. For the hole in the center, sandwich the shim stock between 2 pieces of wood (this minimizes the likelihood of a ragged hole)and drill the spindle hole.

The tighter you clamp the record to the platter, the better (energy from the stylus is transferred from the vinyl to the platter rather than reverberating back to the stylus).
Stevecham
When used correctly, the playing surface of the record is flat to the platter and not dished.

Ditto. I've never had an issue with using the clamp with the rubber washer. The washer will compress plus the label area of the platter is recessed so I'm not sure why your records would be dished. The clamping works perfectly with flat records, and helps with warped records significantly. Add the VPI periphery ring and only badly warped records across the surface will be noticeable.
Clamping can be a little tricky, where there will be slight variances in clamp down pressure with any given record. It takes a bit more time to critically, and correctly clamp, but is probably worth it, just for the fact of better coupling the record to Platter Surface.

You maybe might want to try something like the Herbies Grungebuster VPI Spindle Washer.

Right off the bat, the Rubber Washer is a bit harder in Shore Hardness, and more resistant to compression IMO than the Herbies Spindle Washer. The Grungebuster material seems a little more "spongy", and giving. Rubber can also have a tendency to get harder over time.

With the Herbies Washer, you might be able to achieve a better, and flatter coupling of the record. Mark