Another good Tool for VPI Table


Today I recieved my el cheapo Dial Indicator, and Vacuum Base-Stand from Harbor Freight for $37 shipped.

I knew my VPI HW-19 Mk-IV Platter's 3-point leveling adjustment was slightly off, and the Platter initially showed a .012" "Hump", or +-.006" error. After 15 minutes of adjusting, I got that error down to a .003" "hump", or +- .-0015" error.

For those who have such an adjustment on thier Platters, this might be a good tool to have in one's arsenal.
Mark
markd51
Hi Mark, this is an interesting tool, I adjust my platter leveling rotation by eye but I am sure it is more accurate with a dial indicator. Is it the 30$ one on Amazon? It seems quite cheap for a precision tool !
So do you put one point on the platter turning and any off deviation is recorded by the magnetic base ?
On the VPI 3 points platter I find the easy way by unscrewing the 3 allen screws completely and platter turns flat (by eye ). Thanks for the info.
hello Jloveys,
I don't consider myself a "turntable expert", but from what I once remember I think reading about Harry's/VPI's description, and theories about the 3-point system of the Platter, was that these 3 adjustable Pins were supposed to contact the Bearing Flange, thus offering some isolation, and draining off of resonances-vibrations.

When I got my VPI MK-IV Platter from a very reputable Agon seller, it did appear that all Pins were retracted to the point that they did not contact-touch the Bearing Flange. The runout wasn't bad, but thought it could be better. When I went to adjust by "eye", I knew I only made matters worse, and that it would be a crapshoot, only by a remote lucky chance that I could ever achieve the best adjustment.

Of course we cannot compensate for incorrectly punched Spindle Holes in an LP, or things like a Lip Warp, unless we can lessen it, with a Periphery Ring Clamp, or LP Flattener, I wasn't too happy seeing my wonderful ZYX Airy 3X bobbing slightly up, and down.

I of course have the vaguest idea, just how many High End Tables-Platters incorporate an adjustment system, similar to VPI, such as Galibier, Avid, Walker, Clearaudio, Sota, etc etc, but I would suspect that VPI are not the only ones. Perhaps this is an adjustment often overlooked?

I cannot comment if the one I bought is the same as on Amazon, I'll have to check. The shipment from Harbor Freight could've been slightly faster (A bad time of year to be buying things online), but all arrived perfectly packed. Mark
I'm very familiar with the collimation of Telescope Optics, owning, and having owned many different optical designs over the past 35 years.

Just like Aligning a Optical Mirror, or Lens-Corrective Lens, I found that as one rotates the Platter, one can easily see via Dial indicator, where the high-low spots on the Platter were, and with those areas facing towards the Dial Indicator, one could make the necessary adjustments, of up, or down.

Just like with Optics, I found just a careful slight nudge of the Adjustment Screw, practically a 1/00th of a turn, to where the Screw just began to turn, was almost too groos of an adjustment.

Almost similar (but not as hard) to using a MintLP Protractor, where one goes back, and forth repeatedly, to get the adjustment perfectly set, I concluded that any imperfections were due to reasons other than errors with the adjustment, just as imprections in the Platter machining itself, errors of the Dial Caliper, or lack of getting a perfect final adjustment.

I'll state further, that I made a Paper Mat from an old LP Paper Inner Sleeve to protect the Acrylic Platter's Surface from possibly being scratched by the Dial Indicator's Metal Tip. How much deviance from being true, the makeshift Paper Mat was, I have no idea!?
Mark
As you can see on my system pic I use the 3 point platter as rim drive platter, main platter is the newer superplatter and does not have that 3 point screws anymore. So I think that with inverted bearing it is not so important. Maybe you
could try unscrewing the 3 screws and have total platter/bearing contact and compare the sound by ear with screws tightened to see if there is a real benefit.
Dear Mark, you excited my curiosity and I ordered one . I will try to tweak it for better turntable platter use, as replacing the metal tip by some kind of roller.
But I will inform you. It is an useful device for any TT to check bearing wear. I keep you informed.
Jean.
Jean, The Metal Tip on my Dial Indicator looks like a small Ball Bearing, but it doesn't roll. As a friend mentioned to me, it would as well be a simple matter of covering the tip with a small piece of Cellophane Tape to prevent any acratching of Platter Surface. This would probably insure better accuracy rather than a makeshift Platter Mat.

I would assume VPI would do this service if you sent Platter-Bearing, but the shipping cost alone would probably equate to the cost of the Tools, and then you have them for future use.

The Vacuum Base Stand that I ordered with the Indicator from Harbor Freight is a quite massive, and heavy piece, and very nicely built. The Dial Indicator is as well, a quality piece. I feel I got more than my money's worth with this tool.

I would assume everytime I remove Platter for Lubrication service of Bearing, that getting the Platter positioned exactly again on the Bearing Flange is virtually impossible. Mark

Holy moley Jean, what a system! Very unusual I must say, I never seen such a configuration on a Turntable.
Just awesome! Mark
Thank you Mark. This is a project started with the rediscovery of rim drive benefits over belt drive, but no upgrade from VPI for single motor, so I tried with spare parts and the result is well superior compared to one platter belt drive. The project is so rewarding that I continue with better damping and a new plinth will replace the acrylic one, a sandwich slate/aluminium/carbon full size plinth with a cool design. As always I have to try and compare before adopting a new step in progress. Also mylar belt drive with modified motor rubber shaft soon coming.
The tool you suggest on this thead is essential for proper platter adjustment.
Thanks for the input !
Jean.
Just a tought... this is a two person thread...we have an incredible way of communication so fast that no other way of click and return come far.I am in Belgium you USA just click and instant com. just incredible. Love that.
Well let's make it a three person thread.
Jloveys,
I love what you've done.Looking forward to more pictures as you make changes.Keep up the exploration!!