Prime motor construction

Re: Prime motor construction

Postby Lewisranchmike » Sat Sep 29, 2018 10:26 pm

Mr_Putty wrote:Mike,
Is your motor already in it’s case? Either way is your impression of smoothness given time to break-in? I suggest you hold the motor while running it and move it around. You will likely feel some positions are smoother than others. Keep it moving it and try to encourage it to find smoothness. My Prime motor was pretty rough when I got it. I think it had some dirt in it as there was some dark grease like oil around the shaft that worked its way out. If you see any clean it off. Mine took way more than the typical 20 hours of running to get smooth. However, there was a noticeable improvement at the 20 hour point. I also tried to discourage its vibration patterns by using/altering various types of support pads and adding mass to the top of the housing via a stainless block that I could move around. All this helped smooth out what I think are “average” bearings. I can barely feel my motor vibrate now. The wait was a pain and uncertain. So, I too would like a better motor, someday. The Number9 motor controller claims to greatly improve motor cogging. But it’s not cheap. And any bearings that are not clean and broken in will still be a problem. I can confirm audio improvement as my motor got better. I guess that was part of the risk I took in buying a B-stock table. FWIW, I was told the only difference in new and b-stock was appearance. I can only say to me budget was the deciding factor. No regrets, still tweeking...and liking the results.

Hello MrPutty:

Very good info, I was also thinking it needs a breakin period and will give it a few hours. I use a Eagle motor controller. Love it:0). I have some Herbies Audio material I have bee trying, I put gringbuster disc’s under the feet and a cylinder under the cord where it touches my platform. All seems to help:0).

Best,

Mike
VPI PRIME, VAS Nova Gold, TerraStone Footers, Symposium Seque Iso, Stillpoints LPI, VPI Periphery Ring, Eagle PSU, Roadrunner Tach, Audio Sensibility Statement, ARC Ref Phono 2SE, ARC Ref 5SE, McIntosh MC252, KimberKable 8TC, Vandersteen 3A Sig
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Re: Prime motor construction

Postby Lewisranchmike » Sat Sep 29, 2018 10:30 pm

Packgrog wrote:I would recommend trying out some Herbie's Tenderfeet in place of the standard rubber feet. I have something similar under my motor: stacks of Herbie's extra-thick grungebuster dots on top of Herbie's square big fat dots. These are much better at mitigating vibration transmission than rubber and mouse pads, and more stable as well.

Another thing that I did with my Scout Jr. motor that may not be possible with the newer cylindrical motor housings is that I placed some thin grungebuster material between the top and bottom housing plates to prevent them from ringing like crazy and thereby amplifying the motor vibration. This also worked quite well. Another thing that I tried that worked very POORLY was to try adding mass to the motor pod using either brass weights or a baggie filled with sand. Both dampened vibrations but had an audibly negative impact on the sound. Steel or lead ball bearings might be more effective and synergistic, but I have not tried them, as just the grungebuster damping seemed to work best for me, and I didn't want to risk causing a short by adding conductive material to the inside of the motor housing.

One good way to see if you can benefit from some simple damping would be to gently place your hand on top of the motor housing while listening to music. Can you hear the difference? If so, investigate damping options. If not, there may be something else going on.

Hope that helps a little.


It does help, thanks:0) I also am using Herbies products under motor and under Cord. The real place I feel the vibration is on the cord and I now place a Herbies disc under that so it does not touch the TT platform. Also had a Major improvement going to silk thread from 3 rubber belts..

Best,

Mike
VPI PRIME, VAS Nova Gold, TerraStone Footers, Symposium Seque Iso, Stillpoints LPI, VPI Periphery Ring, Eagle PSU, Roadrunner Tach, Audio Sensibility Statement, ARC Ref Phono 2SE, ARC Ref 5SE, McIntosh MC252, KimberKable 8TC, Vandersteen 3A Sig
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Re: Prime motor construction

Postby Cat5plus » Wed Oct 03, 2018 10:49 am

I guess my question would be for Brf. You mentioned the BLDC motor for the Prime. Is there an alternate A/C motor manufactured that will fit the "Classic" without any modification to the plinth ? I must be lucky either the classic chassis absorbs any small vibrations extremely well (I can not detect "Any vibration at all ) or I just got a "Good One" Never had a problem, but would like a future alternative if it becomes necessary.
VPI Classic Signature 3D, Lyra Titan i, Ortofon MC A90, Eagle, Roadrunner, Pass Labs X-1 pre, Pass Labs X ono Phono, Pass Labs X 250.5, dcs/Berkeley digital, B&W 805D, JL Audio Fathom sub, Cables: Nordost, Siltech.
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Re: Prime motor construction

Postby Brf » Wed Oct 03, 2018 11:06 am

Cat5plus wrote:I guess my question would be for Brf. You mentioned the BLDC motor for the Prime. Is there an alternate A/C motor manufactured that will fit the "Classic" without any modification to the plinth ? I must be lucky either the classic chassis absorbs any small vibrations extremely well (I can not detect "Any vibration at all ) or I just got a "Good One" Never had a problem, but would like a future alternative if it becomes necessary.


Sorry, I have never replaced a Hurst motor with BLDC motor on a VPI table.
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