Turntable "floating platter" attempts

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Hi,
Your platter is floating on the trapped air cushion, not oil - BAD.
You should allow the air to find its way out. Wipe the axle and housing from oil (very carefully), apply small amount of oil on the bottom with a siringe (don't touch the walls) and carefully insert the axle - don't force it. Leave it to seat to its final position by gravity - may take several hours, even a day.
Regards,
Michael
 
Anyway, the rigid coupling platter to plinth through the ball shall be provided, IMO. Think about low frequiency vibrations, need to be sunken into the base and further, to the rake/floor, having the wave lenght of several meters. To be effectively dissipated, the total path within the damping material, should have an order of the wave quater lenght.
 
Well, it's been quite a long time since my original post!

My attempts to create a floating platter were all met with failure, but it was an interesting learning experience. I tried all sorts of oils and different materials for the platters but the oil/liquid bath idea (a platter completely floating on a "tub" of oil) never worked.

I tried a rudimentary air bearing using a small air compressor, but even if I could have gotten that to work, the racket from the air compressor would have drowned out even AC/DC. An air bearing might be the most viable solution for someone who has access to precision milling equipment and a lot more knowledge than I do!

The other thing I never tried was to think small. Like making a floating bearing using the same thinking someone mentioned with the observatory...microns instead of inches.

Just wanted to let everyone know that "the dream" is still alive! But for now, my Music Hall MMF-5 is still going strong and sounding great!
 
Hi Frank,

A couple of years ago I made my DIY turntable . Actually is not all DIY, The arm is a Rega 250 upgraded in the stub and counter weight only so far, Platter from Scheu in Acrylic , almost 5 Kg.

The rest was ..........about my idea and i used a floating sub platter frame , it floats with magnetic levitation. I think this sistem is good , simple and works well. A not too soft or not to stiff suspension.
I attach a picture of it ( not so recent pic, some other tweaks were done on the TT ) .

The magnetic suspension is easy , enable the level adjustment of the platter, the only trouble i had is that i have to replace the centering OR once per year in summer since the OR rubber deteriorate, till they break. In any case they have a low replacement cost , just few Eur. For the motor i used a 5" Floppy disk and a PC 650 Watt feeder, all separate from the Turntable, but inside the round silver Steel case ( quite heavy case with good rubber feet) . The motor is silent and has torque as well. Since i play only LP a fixed bronze pulley does the job.
The plinth is made with 5 layers of marine plywood , inside there are 7 Kg of glued leads. Decoupled spikes by OR and so on...

However my next Turntable project shall be a bit different . Platter made of aluminum and not less than 12 Kg, Bearing with magnetic levitation to reduce the spindle noise, spindle oil lubricated .Arm frame separated from the platter frame, DIY arm 10 " or 12" Unipivot or Shroeder alike , 2 Floppy disk motors with Fly wheel for better speed stability .

I do not have much time , so before to start this new project i need to finish the Washing Record machine under completion.

Regards

Adelmo
 

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Hi,

My bearing has a very tight allowance so the only way to fill the bearing with oilit is to open the bottom part ( that can be removed ) insert the spindle for just 1 mm fiil the bearing with oil , push up the spindle almost to the end, close the bottom part not completely tight allowing the exceeding oil to leak out while you push all the way down the spindle, tight the bottom part to avoid oil leakage. In this way you are sure the oil is there as it is supposed to be even with the tightest spindle/ bearing allowance like mine .

Regards
Adelmo
 
air bearing TT & TA

I was going through some old posts and amazed at how much time i had to experiment back then.
Sent from my TARDIS at the restaurant at the end of the universe while eating Phil.

FYI.
... meanwhile, this is my (DIY) home made concept : air bearing 16" TT & TA
More info:
AIR BEARING 16" TT & TA - Vinyl Engine

It's music .... I like it.
Allez, salukes.

(sent from my leasy chair .... vinyl listening BWV36)
 

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Hi folks!

I' have been playing around with this idea for a few days now and I want to start trying out prototypes this weekend.

If anyone has already attempted this, I would be grateful for any feedback.

I want to attempt a "floating platter". My first ideas were to literally float it in a high viscosity fluid and spin it via magnets in a sub-platter. But I quickly realized it would be slammed into the bottom of the container by the magnets.

Repelling magnetic bearings are too much hassle, and I saw the very complicated setup of the French TT that uses mag-lev.

I may have to settle for a simple elimination of the belt and go with a magnetic sub-platter the couples to the main platter. At least that way I will be able to eliminate any transfer of motor noise.

If anyone has an idea on how to float the platter in liquid, I would be intrested in trying it out.


Hi ,
i have built a turntable with conventional bearing and the platter support is floating by magnetic lievitation. For teh motor i used an old 5" floppy disc that has a great tonque and runs pretty steady as well. The power control is a good quality PC feeder, use a round belt.

Ifi had to built another platter i would use a magnetic lievitation bearing and the motor would be two 5" floppy disc motor and a fly wheel, two belt to delivery all teh torque . It is simple project and i think very perfoming with a torque close to the Lenco or similar ones.
Best regards
Adelmo
 
I did start looking and stumbled onto that one, but (perhaps based solely on 2015 diyaudio thread standards, where some have thousands, even tens of thousands of posts) I didn't think of it as a "mega-thread" - it hasn't even quite got 500 posts!

But it might have been a mega-thread for the time. I was hoping some oldtimer here would point me in the right direction.
 
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