VPI SDS exact speed in .... 40 minutes?

I suppose that is a possibility, but a motor is a pretty simple mechanical devise, and of the many many of them i have had come through here I have never had any issues with the motors. Did you buy a new Dual Drive Station ? How are you checking the speed ? Are you using a SDS ?

If you table ran at speed before you added the dual drive station then the main platter bearing is not the issue.

The only issues I have had is if too much grease is added to the inverted bearings they can bind up causing the speed to vary.

I don't know where you are located but is your close to us here in San Diego your more than welcome to bring it by the shop and I can take a look at it for you.

Good Listening

Peter

Thanks for your offer Peter but Im in the opposite side: Florida.

Yesterday what I have done is run the platter with just one motor and then the other (bypassing the flywheel and one of the motors each time). What is interesting is that the speed is perfect since the beguining. That makes me think that is a flywheel problem, but honestly don't know how that happens: it runs smooth, no noises and have tried using grease and oil with exactly the same results. Any idea?

what Im going to try this evening is run the same test without the SDS and see what happens. What it is interesting is that I need to set the Hz in 58.1 to run the table at 33.33 in the SDS, and should be at 60hz or very close to that right?

Your actual SDS setting is not that relevant it is what ever it is to run at the correct speed, that the setting is not exactly 60Hz is caused by the product the small deviations in all the mechanical interfaces from the motor to the platter. My SDS on one of my tables here in the showroom is set at 59.29.

What belts are you using from the motors to the flywheel ? maybe that is where the culprit is, I use these AS568A-155 Buna N 70 Only use one o ring per motor to the flywheel, then use 4 of the long ones from the flywheel to the platter if that is possible for you. The long ones are not readily available - we make them here from the same type material but thinner and available in 100M spools. If you need some let me know what length and I can make them for you.

Best of luck

Peter

Thanks Peter, just sent you an email to pbnaudio

Agree with pbnaudio - the actual frequency reading on the SDS is irrelevant; it's easy to prove that with different mass centerweights: lighter ones will need lower freq settings, while heavier ones will require higher. The good news is that you can get extremely accurate speeds with the SDS.