On my DIY turtable I designed a classic bearing using a tugsten carbide ball on the needle, but surprise when i tried to insert the spindle in the bearing, pheraps for the very low clearance, the platter floated on the oil without leakage.
😱
😱
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
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
NO, I'm sure that platter is floating on oil, I made a tapered hole beside the thrust plate, inserting oil by this hole the platter raised, it's like an hydrostatic suspension, now I'm trying to understand if I will lose oil from the top of the needle.
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.
Platter is coupled by the side contact between needle and the bronze bearing, lubificating oil is present either in the side interface ( needle / bearing ) and frontal ( ball / thrust plate ) interfaces.
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!
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
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
Attachments
turntable a mercury bath : 
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
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
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.
Sent from my TARDIS at the restaurant at the end of the universe while eating Phil.
air bearing TT & TA
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)
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)
Attachments
That looks so cool. Like it came right out of the TARDIS.
Sent from my TARDIS at the restaurant at the end of the universe while eating Phil.
Sent from my TARDIS at the restaurant at the end of the universe while eating Phil.
the problem with decoupled components like air bearing platters and arms is that there is no where to sink resonant energy it becomes captive within the component. that being the case one would want to build in a lot of loss.
This is an interesting thread, though it's 11 1/2 years old. There's mention of a turntable mega-thread, but I wouldn't know how to look for it. Can someone direct me to it?
There's this potentially helpful 'stickie' thread for Analog Source, but not much is listed there:
http://www.diyaudio.com/forums/analogue-source/104832-favorite-threads-posts-analog-sources.html
There's this potentially helpful 'stickie' thread for Analog Source, but not much is listed there:
http://www.diyaudio.com/forums/analogue-source/104832-favorite-threads-posts-analog-sources.html
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
Who came up with the myth of 'sinking' noise. What you need between platter and earth is mechanical filter that blocks the incoming sources of noise. Isolate the motor and forget about it.
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.
- Status
- Not open for further replies.