You spin me right round

[Æ]

First, to the OP: this is an amazing project.

Second, just saw this solution to the bearing noise problem: http://www.avsforum.com/mag-lev-turntable/

Totally awesome, but unfortunately a couple of decades too late.

[mattk]

First, to the OP: this is an amazing project.

Second, just saw this solution to the bearing noise problem: http://www.avsforum.com/mag-lev-turntable/

[TN Allen]

Already have, done several turntables, quite pleased with the ball bearings compared to the sleeve and single ball. No real difference in noise comparing ball bearings supporting an ebay AR platter & post to the noise from an original AR. The motors produce the audible noise, in my experience. Sent from my LG-V495 using Tapatalk

[Æ]

On the other hand, when possible, and provided resources are available, one should experiment, improved technology doesn't develop itself.

Have at it.

[TN Allen]

On the other hand, when possible, and provided resources are available, one should experiment, improved technology doesn't develop itself.

[Æ]

Sleeve bearings require lubrication, unless they are Oilite, which is noisy against ground steel. I'm not surprised needle bearings were noisy, were they sealed? Did you consider good sealed ball bearings?

The sleeve bearing and single ball is quiet; also less expensive to manufacture to support a platter, which could be one reason this system is used. I'm still curious about actual experience with ball bearings, especially with heavy platters. "Cogging rumble" sounds like a good description of the sound of bearings that are worn and damaged, but not for good sealed ball bearings, if they were to rumble they wouldn't last long in service.

I think I recall reading about recent research regarding manufacturing quiet ball bearings for computer fans, the idea being these are quieter than sleeve bearings. In the long run, given the low platter speed, a sleeve and single ball may be the equivalent of good ball bearings, or visa versa. It would be interesting though to see some valid comparison data.

When something works, stick with it. A brass sleeve and hardened steel spindle with a single thrust ball in the bottom is the way to go, because it works. What however has not been mentioned yet is the lubricant (oil) that should be used. By experience I have found heavier, thicker oils to work best. Something like engine honey.

[TN Allen]

Sleeve bearings require lubrication, unless they are Oilite, which is noisy against ground steel. I'm not surprised needle bearings were noisy, were they sealed? Did you consider good sealed ball bearings?

The sleeve bearing and single ball is quiet; also less expensive to manufacture to support a platter, which could be one reason this system is used. I'm still curious about actual experience with ball bearings, especially with heavy platters. "Cogging rumble" sounds like a good description of the sound of bearings that are worn and damaged, but not for good sealed ball bearings, if they were to rumble they wouldn't last long in service.

I think I recall reading about recent research regarding manufacturing quiet ball bearings for computer fans, the idea being these are quieter than sleeve bearings. In the long run, given the low platter speed, a sleeve and single ball may be the equivalent of good ball bearings, or visa versa. It would be interesting though to see some valid comparison data.

[jjgoertz]

Sounds plausible, but I don't have a clue for a source.
A turntable only needs to do 3 things. Turn silently at a constant speed with no speed variation (wow/flutter). The arm and cartridge do the rest of the work.
I lifted this quote from Alec over at the Vinyl Engine.

I didn't try anything except magnets for the thrust bearing, but for the lateral bearings, the sleeve bearings were audibly much quieter than the needle bearings. It didn't require anything special to tell the difference, I could here the needle bearing from a few feet away, to hear the teflon bushings I need to be within a few inches.

[Whitneyville1]

Sounds plausible, but I don't have a clue for a source.
A turntable only needs to do 3 things. Turn silently at a constant speed with no speed variation (wow/flutter). The arm and cartridge do the rest of the work.
I lifted this quote from Alec over at the Vinyl Engine.

[Æ]

Ball bearings often make a sub-sonic "cogging rumble" noise according to lots of TT builders over on Vinyl Engine. Rumble is a real b*$#@h with TT bearings. An extremely hardened needle point spindle on a single large diameter ball bearing has proven over the years to be the quietest bearing, BUT you must consider the ball bearing to be "sacrificial" with wear. The inside of the spindle shaft should be sacrificial bronze or red brass as steel on both is "self-lubricating". Think engine valve guides.
There's a lot of sophisticated engineering that goes into a top-notch TT.

I plan on using a thrust ball bearing that is made from something other than metal. Delrin, Nylon, Teflon.

[Whitneyville1]

Ball bearings often make a sub-sonic "cogging rumble" noise according to lots of TT builders over on Vinyl Engine. Rumble is a real b*$#@h with TT bearings. An extremely hardened needle point spindle on a single large diameter ball bearing has proven over the years to be the quietest bearing, BUT you must consider the ball bearing to be "sacrificial" with wear. The inside of the spindle shaft should be sacrificial bronze or red brass as steel on both is "self-lubricating". Think engine valve guides.
There's a lot of sophisticated engineering that goes into a top-notch TT.

[jjgoertz]

Made a convex pulley for the motor. Made it a press fit to the motor shaft and turned it in place with the motor running.



My new belt came in and that fixed the small speed variations I was getting. Belt tracking is right where I want it now.



The turntable is pretty much done now, and I'm pleased with the sound and the overall look. Has kind of a sci-fi aesthetic from below.



All it needs now is a power switch, and maybe a switch for 33 and 45 rpm.



Also made a walnut table that turned out pretty well.

[TN Allen]

I was asking about experience with ball bearings, providing support for the weight of the platter as well as rotation. There may be no advantage over a sleeve and single ball, but I'm just curious about others experience and thoughts.

[Æ]

You do nice work, very interesting choices.

I'm wondering if you considered using ball bearings?

There is usually a single thrust bearing (ball) down in the bottom of the bearing sleeve supporting the spindle. Really smooth if oiled up correctly.

[Woofie]

I've ordered a new drive belt, but unfortunately it's back-ordered. I'm hoping it's stiffer than the rubber band because I can hear it slow down in some passages, and I'm thinking it's belt stretch that allows that.

That's awesome, great job.