TT
Bernhard and all concerned,
OK,Ok you have me going again.My God you put in a very long post.Have to counter that somehow,it's begging for it.
Let's agree on something here: naysaying is sometimes a necessary thing to for the sake of the project.
Bernhard ,what I was trying to convey to you in a more subtle way is that I can't help the feeling that you're so deeply,emotionally involved in this and the problems you exprerienced at home with your own TT that somehow to the other participants it seemed a trifle self-serving ?
I have no problem with anyone spouting ideas and frankly I'll do the same.
Somehow the evolution of the project is very hard to follow especially if you pick up somewhere in the middle of it.
So far noone has actually oulined what is expected of a turntable
in its interface and intimate relation to the record we are trying to play.The interaction between the stylus and the vinyl is also to be put into the equation.
My idea of a project like this is to serve the person's need who actually started it.
Anyone remember who it was ? What did this person want ?
See we all forgot about that didn't we ?
Shouldn't it be interactive with him?
I scrolled down the entire page and couldn't find his name on it.
We may have scared him off too.
Then again I may have it all wrong.Am I naysaying here ?Probably yes.
I mentioned it before,I feel this project needs coordination and I leave it to you to find out how.
Don't we all agree this is a daunting project well worthy of being served by all that feel can contribute.
I for one feel so.
Ok so much for the proze.
Bernhard and all concerned,
OK,Ok you have me going again.My God you put in a very long post.Have to counter that somehow,it's begging for it.
Let's agree on something here: naysaying is sometimes a necessary thing to for the sake of the project.
Bernhard ,what I was trying to convey to you in a more subtle way is that I can't help the feeling that you're so deeply,emotionally involved in this and the problems you exprerienced at home with your own TT that somehow to the other participants it seemed a trifle self-serving ?
I have no problem with anyone spouting ideas and frankly I'll do the same.
Somehow the evolution of the project is very hard to follow especially if you pick up somewhere in the middle of it.
So far noone has actually oulined what is expected of a turntable
in its interface and intimate relation to the record we are trying to play.The interaction between the stylus and the vinyl is also to be put into the equation.
My idea of a project like this is to serve the person's need who actually started it.
Anyone remember who it was ? What did this person want ?
See we all forgot about that didn't we ?
Shouldn't it be interactive with him?
I scrolled down the entire page and couldn't find his name on it.
We may have scared him off too.
Then again I may have it all wrong.Am I naysaying here ?Probably yes.
I mentioned it before,I feel this project needs coordination and I leave it to you to find out how.
Don't we all agree this is a daunting project well worthy of being served by all that feel can contribute.
I for one feel so.
Ok so much for the proze.
Re: Bring it On!!
Mark,
Frank,
dunno if private club within the forum is technically possible, but i would not support it, nor would the site owner.
For the record, i do not see anyone governing this project, i do not even call it a project, i call it a creative workshop.
I intercede if i feel that workshop situation is endangered and maybe i overdo it now and then, i am human, i can fail too. But as content is concerned, i am a diyAudio member just as you Frank or as anyone else.
And i personally am more and more afraid to say "we" as i sense that each member's design takes a slightly different path.
BTW, my design more and more gets CNC parts and precision-ground parts. I try to outsmart manufacturing effort but nevertheless :
Expensive parts if one has not the special connections i have ... the special sergeant way i cn go once but not 25 times...
Do i want to force anyone of you to follow my path? a firm NO!! and i deeply apologize if i should have appeared that way.
Can anyone force me to follow his path? Again, no!
Structure:
At the start of this project i also wanted more structure, like you. But when i sensed people did not want it, i stepped back and let the members have what they wanted.
One exception, i insisted on having a spec. A spec describing tasks without hinting to solutions. Now it is there anyone can read it, anyone feel free to ignore it, change it or add to it, it is not my baby, it is nothing more than my suggestion.
Apart from that i do believe we will end up with several differnent designs and we all, me included, will learn way more from it than the Teres group did.
Noone bothered to start a new thread up to now. But anyone of us can do this anytime. And i see no problem making the thread sitting on top of the forum board as this one. I see another problem: suddenly we have a structure (desirable as easier to navigate) but one thing i do not see is how to enforce members to have motor&belt ideas while they are in the motor&belt thread. And i do not want to inhibit ideas (undesirable), i want to encourage ideas! (most desirable
)
Structure applied too early is paralyzing.
Different threads: If you observe how the discussion developped, you will see that it is a task next to impossible to untangle posts and topics, many posts adress more than one topic.
But anyone, feel free to open new threads if you feel a need for it. (i cannot believe i have to point that out, that this is an issue for discussion
)
Then:
we all are spread all over the world. I have started to organize some motor group purchase; i was surprised how few fellows have already noticed or ordered. But, considered the hassle, shipping costs, VAT, customs buying surplus motors and shipping the worldwide is maybe not as attractive as it looked 1st. (all,I am not complaining, i am learning, ok?)
Structure is needed if stuff is ordered IMO. not before.
Let us not forget this is hobby, this is fun, this is no boring company job! And we will have fun
Mark,
fully agreed!Variac said:
Frank,
dunno if private club within the forum is technically possible, but i would not support it, nor would the site owner.
For the record, i do not see anyone governing this project, i do not even call it a project, i call it a creative workshop.
I intercede if i feel that workshop situation is endangered and maybe i overdo it now and then, i am human, i can fail too. But as content is concerned, i am a diyAudio member just as you Frank or as anyone else.
And i personally am more and more afraid to say "we" as i sense that each member's design takes a slightly different path.
BTW, my design more and more gets CNC parts and precision-ground parts. I try to outsmart manufacturing effort but nevertheless :
Expensive parts if one has not the special connections i have ... the special sergeant way i cn go once but not 25 times...
Do i want to force anyone of you to follow my path? a firm NO!! and i deeply apologize if i should have appeared that way.
Can anyone force me to follow his path? Again, no!
Structure:
At the start of this project i also wanted more structure, like you. But when i sensed people did not want it, i stepped back and let the members have what they wanted.
One exception, i insisted on having a spec. A spec describing tasks without hinting to solutions. Now it is there anyone can read it, anyone feel free to ignore it, change it or add to it, it is not my baby, it is nothing more than my suggestion.
Apart from that i do believe we will end up with several differnent designs and we all, me included, will learn way more from it than the Teres group did.
Noone bothered to start a new thread up to now. But anyone of us can do this anytime. And i see no problem making the thread sitting on top of the forum board as this one. I see another problem: suddenly we have a structure (desirable as easier to navigate) but one thing i do not see is how to enforce members to have motor&belt ideas while they are in the motor&belt thread. And i do not want to inhibit ideas (undesirable), i want to encourage ideas! (most desirable
)Structure applied too early is paralyzing.
Different threads: If you observe how the discussion developped, you will see that it is a task next to impossible to untangle posts and topics, many posts adress more than one topic.
But anyone, feel free to open new threads if you feel a need for it. (i cannot believe i have to point that out, that this is an issue for discussion
)Then:
we all are spread all over the world. I have started to organize some motor group purchase; i was surprised how few fellows have already noticed or ordered. But, considered the hassle, shipping costs, VAT, customs buying surplus motors and shipping the worldwide is maybe not as attractive as it looked 1st. (all,I am not complaining, i am learning, ok?)
Structure is needed if stuff is ordered IMO. not before.
Let us not forget this is hobby, this is fun, this is no boring company job! And we will have fun
Frank
Actually I started the thread, but I sure wasn't the creator of this project.
In other threads (most of witch had nothing to do with DIY TT) the subject was discussed.
I thought after a brief conversation with Bernhard to start a thread with a DIYAUDIO TT project.
I have been watching it carefully but really the project is becoming more than I can ever imagine. I'm not really up to it. It's too complex for me.
Maybe I'll do some mods on my TT and then I can learn something and then contribute with the project (that I would love to help in any way I can).
The only real help I think I can give is in making cad drawings. I think i'm good at it.
So if anybody needs a Autocad guy, here I am.
In the respect of the lack of concrete things, I guess that in a open forum like this is very likely to happen.
the wiki page, Is the wrigth place to post the "good stuff" and the forum is the drawing board.
I believe that bernhard should be the "project manager" of that wiki page, and in the forum, well everione has the rigth to his/her oppinion.
Actually I started the thread, but I sure wasn't the creator of this project.
In other threads (most of witch had nothing to do with DIY TT) the subject was discussed.
I thought after a brief conversation with Bernhard to start a thread with a DIYAUDIO TT project.
I have been watching it carefully but really the project is becoming more than I can ever imagine. I'm not really up to it. It's too complex for me.
Maybe I'll do some mods on my TT and then I can learn something and then contribute with the project (that I would love to help in any way I can).
The only real help I think I can give is in making cad drawings. I think i'm good at it.
So if anybody needs a Autocad guy, here I am.
In the respect of the lack of concrete things, I guess that in a open forum like this is very likely to happen.
the wiki page, Is the wrigth place to post the "good stuff" and the forum is the drawing board.
I believe that bernhard should be the "project manager" of that wiki page, and in the forum, well everione has the rigth to his/her oppinion.
Pedro,
this is not too complex, i fervently disagree. I was saying, several pathes are developing. One of them will suit your needs and your workshop, i am sure ............ ..😴
this is not too complex, i fervently disagree. I was saying, several pathes are developing. One of them will suit your needs and your workshop, i am sure ............ ..😴
Bernhard,
I really don't doubt your capability of delivering this project to a safe harbor, the only thing I doubt is if I can actually do it.
I see much precision, fine tolerances and materials that I don't know if I'm capable of.
(did you see my SOZ amp? that was the best I could do then, although I believe my next two amps will be far better regarding the mechanical stuff)
I really don't doubt your capability of delivering this project to a safe harbor, the only thing I doubt is if I can actually do it.
I see much precision, fine tolerances and materials that I don't know if I'm capable of.
(did you see my SOZ amp? that was the best I could do then, although I believe my next two amps will be far better regarding the mechanical stuff)
TT
To all,
The following text is meant to be read with a smile on everyone's face,it is knowingly written tongue in cheek style in layman's terms so that all DIY amateurs know exactly what they're up against.
No offense is meant by it,just wanted it to be a relaxing piece to read as an intermezzo and to put some things into perspective.
Allright so you want some explanation on what I claimed before:
-Regarding the vacuum bearing,platter materials and more:
I remember many a full moon ago I was breaking my head over it and the problem is closely related to exactly the same problem the designers of the mecury floater had as well.
The airbearing that is.
*I will not elaborate on the mercury any further here unless someone specifically asks.*
Problem:
- one needs a decent mass for a platter to sink the energy/vibration generated by the stylus/record into and also to provide sufficient gyroscopic momentum to keep it running stably.
A 20 Kg platter is a good start,the more the merrier but we have other design parameters to consider.
This high mass will store this energy till it eventually gets converted to heat.
Still we do not want this energy to travel back to the surface where the record is spinning so it will interfere with the task of our cartridge and getting picked up again .(seriously scrambled and time delayed.)
-We want our platter to be as sonically dead not having,or as little as possible a sonic footprint of its own.
-We want the energy to get dissipated (this takes time) and travel away from where it originated and give it an as easy as possible path to do that.
Moreover we don't want it to circle around and search for a way out.We need to provide it with an easy path away from our platter into a mass were it can be safely stored till it dissipates into heat.
It is at this point that we have to consider the characteristics of our materials carefully.**
Now if we would use a floating system such as the airbearing to rotate our platter on you will already see one problem:
We lost our gateway to the outer world,our energy is stuck in the platter.Not so good.
But.I hear you say, air transmits vibration well,I've been told?
Sure,sure you absolutely right,they didn't say they meant low frequency vibes, did they ?
High frequecies behaves in a very different way and to cross from one materiel into another they're not likely to travel as airwaves.
And there are other "minor" problems : we are going to need a hefty (noisy too) pump to lift our platter steadily ,(we are going to need a smoothing tank as well since our pump is pulsating air into our bearing) probably 10 to 15 meters of aquarium hose to the next room,find a way to tell people not to close that door and keep their feet of that hosing.The kids must be taught not to pull that hose whilst daddy is listening and since you're going to put them in that room where you have these mighty pumps, don't forget to tell 'em they're not allowed to breathe in there either since there's not that much air left anyway.
If they don't obey we end up with a "small " mishap and depending on the system even a twisted cantilever in our xxxx dollar/euro cartridge.
If you're lucky and you have installed the smoothing tank the airpressure is going to get down gradually.Lucky you.
Do I digress?Satirical?Nah.
Moreover that airpressure needs to be kept constant all the time day in day out no matter what wheather and other barometric changes of our environment.
You've been spending a forthnight trying to figure out why that VTA just doesn't seem right only to find out later on there's a small leak somewhere along the feed causing a pressure drop.
OK,you get the picture.
We start out with a 20 Kg platter.What if I'd tempted you with the sexappeal,ultimate, unstoppable 40 to 50 Kg beast?
And,in case you forget ,we have to spin this baby around now don't we?And you want a belt for that too?Very well...
But hey, our air bearing is floating right?So if we have this belt around this floating mass it is going to stand on its feet when our motor start pulling it from the side right ?
I don't think so.We're actually kicking our mass which is in mid air while we are still standing solidly on the ground.Houston we have a probl...
And the good news is that somehow I know of a way to solve this,again at the expense of simplicity. (And I won't quote Einstein on this one.)
-Now the motor, in case you're still with me :
Anyone ever thought of why all these fancy dc motors all of sudden work "better" when they are controlled by PLL locked fully
feedbacked (which works per defintion after the error has occured) super servo looped devices are going to work better all of a sudden ?All that from a measly low current psu?
No,me I want a good juicy ac motor,my motor is going to be fed from the most powerful source I find at home.The local powergrid.
It will start up my 50 kilo platter on it's solid ball bearing no sweat in 15 secs tops.
My silicone loaded belt will smooth over any start up glitch present
and once we have our platter spinning at precisely 33.3333 rpm it can go to sleep.That simple.
Provided I get the bearing right,put it where it should be and no, I don't mind I have to stop it from spinning by hand.
Of course I can design a set of Porsche breaks for you as well.
Anyone care to calculate the momentum of a 50 kg platter spinning at 33.33 ? Go ahead and grab that calc.
We're talking tons here.
😎
And maybe you would like to have a 45 Rpm speed on it as well ?
Not to worry,that part is a piece of cake really.I admit though that stopping the platter by hand at this speed...well let's just say it will warm you're hands up on those cold winter nights just enough to comfortably change records.No kidding.
So this was it for tonight really.Promise I continue as soon as I can.
**So what materials am I talking about ? How will I calculate belt lenght,motor pulley and throat ?
Well we'll get to that in due time won't we ?
Do I dismiss all other ideas beforehand?'Course not.This is just my way of sharing my ideas and naturally you can have a field day picking my brain.Up to a point fellows.
Good night you all,
To all,
The following text is meant to be read with a smile on everyone's face,it is knowingly written tongue in cheek style in layman's terms so that all DIY amateurs know exactly what they're up against.
No offense is meant by it,just wanted it to be a relaxing piece to read as an intermezzo and to put some things into perspective.
Allright so you want some explanation on what I claimed before:
-Regarding the vacuum bearing,platter materials and more:
I remember many a full moon ago I was breaking my head over it and the problem is closely related to exactly the same problem the designers of the mecury floater had as well.
The airbearing that is.
*I will not elaborate on the mercury any further here unless someone specifically asks.*
Problem:
- one needs a decent mass for a platter to sink the energy/vibration generated by the stylus/record into and also to provide sufficient gyroscopic momentum to keep it running stably.
A 20 Kg platter is a good start,the more the merrier but we have other design parameters to consider.
This high mass will store this energy till it eventually gets converted to heat.
Still we do not want this energy to travel back to the surface where the record is spinning so it will interfere with the task of our cartridge and getting picked up again .(seriously scrambled and time delayed.)
-We want our platter to be as sonically dead not having,or as little as possible a sonic footprint of its own.
-We want the energy to get dissipated (this takes time) and travel away from where it originated and give it an as easy as possible path to do that.
Moreover we don't want it to circle around and search for a way out.We need to provide it with an easy path away from our platter into a mass were it can be safely stored till it dissipates into heat.
It is at this point that we have to consider the characteristics of our materials carefully.**
Now if we would use a floating system such as the airbearing to rotate our platter on you will already see one problem:
We lost our gateway to the outer world,our energy is stuck in the platter.Not so good.
But.I hear you say, air transmits vibration well,I've been told?
Sure,sure you absolutely right,they didn't say they meant low frequency vibes, did they ?
High frequecies behaves in a very different way and to cross from one materiel into another they're not likely to travel as airwaves.
And there are other "minor" problems : we are going to need a hefty (noisy too) pump to lift our platter steadily ,(we are going to need a smoothing tank as well since our pump is pulsating air into our bearing) probably 10 to 15 meters of aquarium hose to the next room,find a way to tell people not to close that door and keep their feet of that hosing.The kids must be taught not to pull that hose whilst daddy is listening and since you're going to put them in that room where you have these mighty pumps, don't forget to tell 'em they're not allowed to breathe in there either since there's not that much air left anyway.
If they don't obey we end up with a "small " mishap and depending on the system even a twisted cantilever in our xxxx dollar/euro cartridge.
If you're lucky and you have installed the smoothing tank the airpressure is going to get down gradually.Lucky you.
Do I digress?Satirical?Nah.
Moreover that airpressure needs to be kept constant all the time day in day out no matter what wheather and other barometric changes of our environment.
You've been spending a forthnight trying to figure out why that VTA just doesn't seem right only to find out later on there's a small leak somewhere along the feed causing a pressure drop.
OK,you get the picture.
We start out with a 20 Kg platter.What if I'd tempted you with the sexappeal,ultimate, unstoppable 40 to 50 Kg beast?
And,in case you forget ,we have to spin this baby around now don't we?And you want a belt for that too?Very well...
But hey, our air bearing is floating right?So if we have this belt around this floating mass it is going to stand on its feet when our motor start pulling it from the side right ?
I don't think so.We're actually kicking our mass which is in mid air while we are still standing solidly on the ground.Houston we have a probl...
And the good news is that somehow I know of a way to solve this,again at the expense of simplicity. (And I won't quote Einstein on this one.)
-Now the motor, in case you're still with me :
Anyone ever thought of why all these fancy dc motors all of sudden work "better" when they are controlled by PLL locked fully
feedbacked (which works per defintion after the error has occured) super servo looped devices are going to work better all of a sudden ?All that from a measly low current psu?
No,me I want a good juicy ac motor,my motor is going to be fed from the most powerful source I find at home.The local powergrid.
It will start up my 50 kilo platter on it's solid ball bearing no sweat in 15 secs tops.
My silicone loaded belt will smooth over any start up glitch present
and once we have our platter spinning at precisely 33.3333 rpm it can go to sleep.That simple.
Provided I get the bearing right,put it where it should be and no, I don't mind I have to stop it from spinning by hand.
Of course I can design a set of Porsche breaks for you as well.
Anyone care to calculate the momentum of a 50 kg platter spinning at 33.33 ? Go ahead and grab that calc.
We're talking tons here.
😎
And maybe you would like to have a 45 Rpm speed on it as well ?
Not to worry,that part is a piece of cake really.I admit though that stopping the platter by hand at this speed...well let's just say it will warm you're hands up on those cold winter nights just enough to comfortably change records.No kidding.
So this was it for tonight really.Promise I continue as soon as I can.
**So what materials am I talking about ? How will I calculate belt lenght,motor pulley and throat ?
Well we'll get to that in due time won't we ?
Do I dismiss all other ideas beforehand?'Course not.This is just my way of sharing my ideas and naturally you can have a field day picking my brain.Up to a point fellows.
Good night you all,
Re: TT
well the angular momentum is not the main problem as i see it.
If you have a very large and very heavy plate. a very small assimetry could generate heavy vibrations that would rock your TT. so if you go massive you must be very precise.
just spin a bicycle tyre and see what am i talking about
fdegrove said:
well the angular momentum is not the main problem as i see it.
If you have a very large and very heavy plate. a very small assimetry could generate heavy vibrations that would rock your TT. so if you go massive you must be very precise.
just spin a bicycle tyre and see what am i talking about
TT
Bernhard,
Get yr. message.Need more time though.
Unfortunately I spotted it too late.I was erroneously writing a reply in a new thread and to add insult to injury I have still to read the wiki as well.
Damn...
Still I'm glad to see we found some consensus.
My post,isn't a post really.
I just needed a working platform and hope nobody objects to the fact I decided to pour it into a mini-series of articles.
If you or anyone else decides to put it into the trash just go ahead.
Cheers.
Bernhard,
Get yr. message.Need more time though.
Unfortunately I spotted it too late.I was erroneously writing a reply in a new thread and to add insult to injury I have still to read the wiki as well.
Damn...
Still I'm glad to see we found some consensus.
My post,isn't a post really.
I just needed a working platform and hope nobody objects to the fact I decided to pour it into a mini-series of articles.
If you or anyone else decides to put it into the trash just go ahead.
Cheers.
TT
Pedro,
I just notice you're browsing the site.
Just hang in their,at the end you still will find usefull stuff for yourself.
You sure have us on a rollercoaster with this one.
"so if you go massive you must be very precise"
You always have to,and there more than that too.
Regards,
Pedro,
I just notice you're browsing the site.
Just hang in their,at the end you still will find usefull stuff for yourself.
You sure have us on a rollercoaster with this one.
"so if you go massive you must be very precise"
You always have to,and there more than that too.
Regards,
frank
i'm here all rigth!
if help is needed in the math&phisics and cad department just ring the bell
i'm here all rigth!
if help is needed in the math&phisics and cad department just ring the bell
No, I'm not dropping out, I'm just thinking my ideas over and want to build a proto to check if there is something in it. Sadly time is lacking at the moment.
As for building anything:
1: Physics rule, whatever the self-proclaimed audio prophets say. A wave is a wave is a wave and it will behave like one.
2: Engineering is the knowledge to apply the laws of physics to a real problem and compromise on them to achive a set goal.
As for building anything:
1: Physics rule, whatever the self-proclaimed audio prophets say. A wave is a wave is a wave and it will behave like one.
2: Engineering is the knowledge to apply the laws of physics to a real problem and compromise on them to achive a set goal.
Enough philosophy. Okay, it took me some time to read all that and do some preliminary digestion. What follows next are some thoughts, random, but related to several posts and topics raised. Please, DO NOT THINK THEY ARE NEGATIVE. Oh well, some are but then I know I have a reputation for being negative 🙂 It is meant to get some second reflections, and a bit more brainstorming. I also think that we (and the occasional outside reader) might benefit from a deeper explanation on some points.
****DISCLAIMER****
Now, please do not consider this as hostile to all what is said and reached so far. It is also never raised against someone! This is pure technical, but maybe it could be better writen.
******************
1: energy at point of contact: Can anybody give me a figure of how much energy in the form of vibrations is generated at the lp-stylus interface? I consider this at most a 5th order disturbance.
2: storing and dissipating energy: the energy we are dealing with in this case are vibrations. For storing we need a spring, for dissipating we need damping, best internal in the material as transfering it from material to material gives reflections. Unless we want a material with gradually changing density. Might be something in it....ideas? So we need a stiff material with high internal damping, probably some composite.
3: giant platter weight: Yes, we need a heavy platter, but it does not need to be heavier than needed to overcome fast iregularities of the drive system. Forget a platter that can turn a whole side without dropping speed. This will need to be larger than the diameter of an lp. Mass is not the most important in the storage of rotational energy, rpm is. Remember, most flywheel systems have air or magnetic bearings! Impact on the bearing also!
4: noise of the compressor: Good point, but can be overcome. And yes, a large tank is needed but no rocket science. I do not intend to let it run when not listening music. When the TT is not in use it lands. So we need some landing gear, right? (ideas please!)
5: size of the compressor: well, this depend directly on the weight of the platter and the diameter of it. It does not need to be large. Probably more dependent on what you can get your hands on. If silent operation needed, gaz cylinders may be used (CO2 or N).
6: pressure regulator: Needed, but possible. Also oil separator.
7: drive system: Personally I dislike belt drive and DC motors (in that order). The only way the platter can smooth the speed, is if it is elastically connected to the motor or if slip is possible. Both are out of the question for me. So it only leaves hard locked direct drive. To be honest, I do not have a diy solution for that yet. (BTW I tought about the proposed controller. It IS a pll. The only way there are no up/down pulses arriving at the counter is when both edges fall at the same time! So given enough time it will lock) The proposed system has the advantage that the motor with its noise can be further away than in a direct drive.
8: thick platter: the thicker it gets, the closer we come to the wavelenghts involved, more chance for reflections and interference patterns if you consider 1 important.
9: vacuum lp holder: This I do not get. If your lp is flat, then a reasonable weighted clamp is all you need. If it is warped, clamp or vacuum will help, but not cure. So I go for the simpler option. If the warp is very bad, vacuum will not seal around the edge unless a very thick soft seal is used, but how good will the contact be then? Again an overkill solution. (and yes, I have some records that are very badly wraped, they stayed in the back of a car on a sunny day)
10: ball bearing above gravity center: Dynamic stabillty will be worse than air bearing. Once the stylus is on the lp, center of mass shifts and vibrations can set in. Center also shifts while playing.
11: vibration isolation from the floor: Can we consider this a second "project"? Anyway it will depend to much on how the TT is constructed, and it is clear by now there will not be 2 the same of this one.
12: bellies and nodes: quite evident you need to place them at the bellies. The nodes stand still, so connecting a still point to another still point does not change much I would think.
13: oil bath: I don't know how much oil you guys want to use, but I find it scary. Even worse for mercury. I admit, I wanted thirteen points 🙂
Okay, so that is it for the moment. My biggest problem is spare time, followed by access to equipment, certainly a lathe (and its operator). Let the stream of ideas come...........
****DISCLAIMER****
Now, please do not consider this as hostile to all what is said and reached so far. It is also never raised against someone! This is pure technical, but maybe it could be better writen.
******************
1: energy at point of contact: Can anybody give me a figure of how much energy in the form of vibrations is generated at the lp-stylus interface? I consider this at most a 5th order disturbance.
2: storing and dissipating energy: the energy we are dealing with in this case are vibrations. For storing we need a spring, for dissipating we need damping, best internal in the material as transfering it from material to material gives reflections. Unless we want a material with gradually changing density. Might be something in it....ideas? So we need a stiff material with high internal damping, probably some composite.
3: giant platter weight: Yes, we need a heavy platter, but it does not need to be heavier than needed to overcome fast iregularities of the drive system. Forget a platter that can turn a whole side without dropping speed. This will need to be larger than the diameter of an lp. Mass is not the most important in the storage of rotational energy, rpm is. Remember, most flywheel systems have air or magnetic bearings! Impact on the bearing also!
4: noise of the compressor: Good point, but can be overcome. And yes, a large tank is needed but no rocket science. I do not intend to let it run when not listening music. When the TT is not in use it lands. So we need some landing gear, right? (ideas please!)
5: size of the compressor: well, this depend directly on the weight of the platter and the diameter of it. It does not need to be large. Probably more dependent on what you can get your hands on. If silent operation needed, gaz cylinders may be used (CO2 or N).
6: pressure regulator: Needed, but possible. Also oil separator.
7: drive system: Personally I dislike belt drive and DC motors (in that order). The only way the platter can smooth the speed, is if it is elastically connected to the motor or if slip is possible. Both are out of the question for me. So it only leaves hard locked direct drive. To be honest, I do not have a diy solution for that yet. (BTW I tought about the proposed controller. It IS a pll. The only way there are no up/down pulses arriving at the counter is when both edges fall at the same time! So given enough time it will lock) The proposed system has the advantage that the motor with its noise can be further away than in a direct drive.
8: thick platter: the thicker it gets, the closer we come to the wavelenghts involved, more chance for reflections and interference patterns if you consider 1 important.
9: vacuum lp holder: This I do not get. If your lp is flat, then a reasonable weighted clamp is all you need. If it is warped, clamp or vacuum will help, but not cure. So I go for the simpler option. If the warp is very bad, vacuum will not seal around the edge unless a very thick soft seal is used, but how good will the contact be then? Again an overkill solution. (and yes, I have some records that are very badly wraped, they stayed in the back of a car on a sunny day)
10: ball bearing above gravity center: Dynamic stabillty will be worse than air bearing. Once the stylus is on the lp, center of mass shifts and vibrations can set in. Center also shifts while playing.
11: vibration isolation from the floor: Can we consider this a second "project"? Anyway it will depend to much on how the TT is constructed, and it is clear by now there will not be 2 the same of this one.
12: bellies and nodes: quite evident you need to place them at the bellies. The nodes stand still, so connecting a still point to another still point does not change much I would think.
13: oil bath: I don't know how much oil you guys want to use, but I find it scary. Even worse for mercury. I admit, I wanted thirteen points 🙂
Okay, so that is it for the moment. My biggest problem is spare time, followed by access to equipment, certainly a lathe (and its operator). Let the stream of ideas come...........
TT
Hello Havoc and all participants,
Allow me to go through the points you make and add some comments,qq.
1/I don't know an exact figure,it might be small in numbers.To me it's number two on my list.The other being the bearing platter interface.(In a more convential design at least.)
I deliberately ignore airborne vibrations,although also of importance in the whole of the picture.
2/I want materials of gradually changing density,chosen for the task at hand in which case reflections will not be a problem.
This is what I mean by impedance matching and mechanical diode application.For the lp-stylus interface metacrylate is excellent.
For the bearing-platter interface any high mass rigid material is O.K.For the ball bearing (my choice,I know) I will use a tungsten-carbide ball.
3/I disagree.Rpm ??Can you explain ?Whatever other bearing types are chosen for other applications in the industry is not relevant here.A design is a whole lot of trees forming a forest,we seek synergetic behaviour.
4/5/Ok,if it MUST be an air bearing.You raise some good points against it already.Landing gear:magnets ?
I don't think gascylinders (Nitrogen filled !!!) are an option.You operate an open,lossy circuit.
6/Pressure control OK.Oil seperator?I don't understand,sorry.
7/Hard locked direct drive ac motor??I don't see how you will circumvent belt drive here unless you would use a turbine within your air bearing .(I patent this one).
Direct drive is out of the equation.Motor (your choice) is out too if turbine controlled.
Reading your last sentence:if you mean in a belt driven system with the pll dc motor I can only say why can't you do this with an ac motor ?
You need both some slip and elasticity in your belt or you can't start up your heavy platter without it either slipping or breaking.
Newton's idea not mine.
8/Opt for split-platter design.High mass at the bottom part.See also 2/
9/I agree.if your records are in such bad shape replace them where possible.
10/Didn't know this was put forward somewhere.Wiki?I would put the bearing at the very bottom of the high mass platter for more than one reason.
11/Absolutely agree.
12/Again agreed.
13/Well you had your 13 points.I don't even want to dignify this ludicrous suggestion.
Thank you for yr. input,
Hello Havoc and all participants,
Allow me to go through the points you make and add some comments,qq.
1/I don't know an exact figure,it might be small in numbers.To me it's number two on my list.The other being the bearing platter interface.(In a more convential design at least.)
I deliberately ignore airborne vibrations,although also of importance in the whole of the picture.
2/I want materials of gradually changing density,chosen for the task at hand in which case reflections will not be a problem.
This is what I mean by impedance matching and mechanical diode application.For the lp-stylus interface metacrylate is excellent.
For the bearing-platter interface any high mass rigid material is O.K.For the ball bearing (my choice,I know) I will use a tungsten-carbide ball.
3/I disagree.Rpm ??Can you explain ?Whatever other bearing types are chosen for other applications in the industry is not relevant here.A design is a whole lot of trees forming a forest,we seek synergetic behaviour.
4/5/Ok,if it MUST be an air bearing.You raise some good points against it already.Landing gear:magnets ?
I don't think gascylinders (Nitrogen filled !!!) are an option.You operate an open,lossy circuit.
6/Pressure control OK.Oil seperator?I don't understand,sorry.
7/Hard locked direct drive ac motor??I don't see how you will circumvent belt drive here unless you would use a turbine within your air bearing .(I patent this one).
Direct drive is out of the equation.Motor (your choice) is out too if turbine controlled.
Reading your last sentence:if you mean in a belt driven system with the pll dc motor I can only say why can't you do this with an ac motor ?
You need both some slip and elasticity in your belt or you can't start up your heavy platter without it either slipping or breaking.
Newton's idea not mine.
8/Opt for split-platter design.High mass at the bottom part.See also 2/
9/I agree.if your records are in such bad shape replace them where possible.
10/Didn't know this was put forward somewhere.Wiki?I would put the bearing at the very bottom of the high mass platter for more than one reason.
11/Absolutely agree.
12/Again agreed.
13/Well you had your 13 points.I don't even want to dignify this ludicrous suggestion.
Thank you for yr. input,
3: From memory, it might be incorrect: The inertial moment of a cilinder is I=mr^2/2, so rotational energy is Iw^2 where w=2.pi.f, f the rotational frequency. So stored energy is proportional to the mass, proportional to the square of the radius and proportional to the square of the rotational speed. Just plain physics.
This is why flywheels, whose duty it is to store enegry for a long time always are large is diameter and rotate at a very high speed. In fact, the mass is mostly kept low! Limiting factor is the tensile strenght in the rim.
6: all compressors loose oil. At least those giving enough pressure for this application. There are special ones for food industry but you will not be wanting to know the price.
7: Bad text. I need a direct driven platter where the motor is locked by a fast acting pll and always in lock. For me it may take up to 2min to start. AC motors can be used, but the electronics needed to pll those are a grade above those for dc motors. Also you need to keep them away a lot further than dc motors. I know, I'm strugling to get the hum out of my lenco, and it comes from the ac motor used even when separated by steel plate and 1cm Alu.
10: are you sure you read all the posts? This design was proposed after the air bearing as an alternative. Please explain how you intend to balance a high mass platter on top of a ball.
This is why flywheels, whose duty it is to store enegry for a long time always are large is diameter and rotate at a very high speed. In fact, the mass is mostly kept low! Limiting factor is the tensile strenght in the rim.
6: all compressors loose oil. At least those giving enough pressure for this application. There are special ones for food industry but you will not be wanting to know the price.
7: Bad text. I need a direct driven platter where the motor is locked by a fast acting pll and always in lock. For me it may take up to 2min to start. AC motors can be used, but the electronics needed to pll those are a grade above those for dc motors. Also you need to keep them away a lot further than dc motors. I know, I'm strugling to get the hum out of my lenco, and it comes from the ac motor used even when separated by steel plate and 1cm Alu.
10: are you sure you read all the posts? This design was proposed after the air bearing as an alternative. Please explain how you intend to balance a high mass platter on top of a ball.
I go away for a few days and look what happens...🙁
I don't like what I read😡 .
Frank, no matter how often you say that we shouldn't be offended by what you write I am. All I read is why things can't work but no constructive participation. At all.
What reasons. Explain.
I stop here. I don't want to have a very interesting thread get sidetracked.
So far this thread has been a kind of brainstorm, at least that is how I consider it. In a brainstorm it is very important to let everybody have his say, however wacky you may think it is, without dismissing the idea. It just might trigger a thought that does make sense.
It has not been about final solutions (eventhough some sugestions may turn into one). We have only just reached a point that some principles AND ONLY THE PRINCIPLES may be tested. Actual size, material, construction and detail solutions are at best hinted at. All this takes time and a lot of trial and no doubt error. There comes a moment that we have to decide what is useful and what is not but I feel we are not there yet.
My guess it that in the end we have a few valid basic solutions that offer different levels of sophistication, cost and complexity. You then decide what suits your needs best.
Back to work.😎
I am still working on my unipivot&oil prototype (however ludicrous). Yesterday I got the materials for my platter and bearing so I can move forward again. I guess that somewhere next week it will be done. Without a motor though, so untill then I am limited in what I can test. Let you all know the results asap.
Peter
I don't like what I read😡 .
Frank, no matter how often you say that we shouldn't be offended by what you write I am. All I read is why things can't work but no constructive participation. At all.
How wonderful. But what is it to us if you don't say how.
Maybe you should take a few more hours than three to read what has gone before. I myself have read this thread trough a couple of times and each time I saw new things I missed before.
What reasons. Explain.
And you don't mean to offend? Perhaps it is ludicrous. I don't know. But saying so without any explanation sure doesn't convince me.
I stop here. I don't want to have a very interesting thread get sidetracked.
So far this thread has been a kind of brainstorm, at least that is how I consider it. In a brainstorm it is very important to let everybody have his say, however wacky you may think it is, without dismissing the idea. It just might trigger a thought that does make sense.
It has not been about final solutions (eventhough some sugestions may turn into one). We have only just reached a point that some principles AND ONLY THE PRINCIPLES may be tested. Actual size, material, construction and detail solutions are at best hinted at. All this takes time and a lot of trial and no doubt error. There comes a moment that we have to decide what is useful and what is not but I feel we are not there yet.
My guess it that in the end we have a few valid basic solutions that offer different levels of sophistication, cost and complexity. You then decide what suits your needs best.
Back to work.😎
I am still working on my unipivot&oil prototype (however ludicrous). Yesterday I got the materials for my platter and bearing so I can move forward again. I guess that somewhere next week it will be done. Without a motor though, so untill then I am limited in what I can test. Let you all know the results asap.
Peter
TT
Hello Havoc,
Thks reply,
There are still some minor points you got me confused on.
I think its more a matter of expressing things than actual fact though.(it's not easy to do)
3: giant platter weight: Yes, we need a heavy platter, but it does not need to be heavier than needed to overcome fast iregularities of the drive system. Forget a platter that can turn a whole side without dropping speed. This will need to be larger than the diameter of an lp. Mass is not the most important in the storage of rotational energy, rpm is. Remember, most flywheel systems have air or magnetic bearings! Impact on the bearing also!
3/Giant platter weight: everything being relative of course I rather go for high mass then too low a mass.High mass is a long term energy sink and since I want high rotational stablity as well,I go for that.I'd surely welcome a platter that could spin an entire lp-side without losing speed but that would need to be absolutely free of friction and of very,very high rotatoinal mass.It does not necessarily have to be of wider diameter than the lp itself but that would evidently help.
So,in practice you would choose to put some heavy material at the rim to increase rotational mometum.Here I suggest lead for it has high mass and low Q.Doing so will achieve three goals in one go since we also introduce a non-resonant energy sink (qf=3Hz),and lower our center of gravity.(i.e. where I want it to be)
6/Ok.I understand,you mean an industrial aire compression system.I was thinking about a membrane type you see.An airfilter at the intake to I reckon?
7/This is one area where high rotational mass is very handy.It will ease the burden of it's locomotive force,the motor.I think absolute rocksolid rotation of the motor pulley is far more critical on low mass platter designs.(just a tip for the ac motor of yr Lenco : use a mumetal shield iso alu and ground the shield)
I agree on regulation of the a.c. motor being harder to achieve,but I prefer it's brute force approach provided all else is up to par.
Both have pro's and con's of course.(Hang on folks we'll explain later on.)
As with most things:all depends on what you need and how you integrate it with the rest of the design.Belt and belt materials come to mind.
10/When I read yr. previous post I somehow thought you meant I had suggested it,which I didn't.
Here comes the more unconventional part:since I use a high mass primary platter, (remember I suggested a split design),this platter is going to be around 15 cm high,32cm diam.
Since my bearing housing is fixed on the plinth (going through it) and is relatively short but wide (roughly :bearing height 2.5 cm width of top 3 cm diam.) Actual shape of its top is the same as a simple round hat looked at from the top.The rim of the hat is only a few mm away from the plinth's top.
Actually the plith and it's function should not be overlooked either in view of system integration.It plays an important role.
Now I use this top to put my primary platter on (50 Kg of solid stainless steel)which has a recess in the center of 3cm diam. and 1 cm depth, as well making for intimate contact plus relatively large contact area (tight coupling is not what I want here)I achieve stabilty by weight and the overhang on the bottom.
You can well imagine that if I now attach the belt around 3 cm height from the bottom of the platter and use a good elastomer for belt material it is by no means possible to tilt the platter.(I invite you to try it even with you bare hands,it won't move.)
The choice of belt is another topic of debate,certainly not unimportant either.
Why else,you might ask do I want my bearing to sit this low?
Apart from the stabilty (both dynamic and static) I achieve also that my bearing ,which will always induce some chatter no matter what you do, is far enough removed from the surface that by the time it reaches my top platter (remember I use a split platter design)it will have absorbed and dissipated any spurious energy emanating from it in the high mass.
Whatever may still reach the top will not carry much energy.
Hope this has clarified some points under scrutiny.
Rgds,
Hello Havoc,
Thks reply,
There are still some minor points you got me confused on.
I think its more a matter of expressing things than actual fact though.(it's not easy to do)
3: giant platter weight: Yes, we need a heavy platter, but it does not need to be heavier than needed to overcome fast iregularities of the drive system. Forget a platter that can turn a whole side without dropping speed. This will need to be larger than the diameter of an lp. Mass is not the most important in the storage of rotational energy, rpm is. Remember, most flywheel systems have air or magnetic bearings! Impact on the bearing also!
3/Giant platter weight: everything being relative of course I rather go for high mass then too low a mass.High mass is a long term energy sink and since I want high rotational stablity as well,I go for that.I'd surely welcome a platter that could spin an entire lp-side without losing speed but that would need to be absolutely free of friction and of very,very high rotatoinal mass.It does not necessarily have to be of wider diameter than the lp itself but that would evidently help.
So,in practice you would choose to put some heavy material at the rim to increase rotational mometum.Here I suggest lead for it has high mass and low Q.Doing so will achieve three goals in one go since we also introduce a non-resonant energy sink (qf=3Hz),and lower our center of gravity.(i.e. where I want it to be)
6/Ok.I understand,you mean an industrial aire compression system.I was thinking about a membrane type you see.An airfilter at the intake to I reckon?
7/This is one area where high rotational mass is very handy.It will ease the burden of it's locomotive force,the motor.I think absolute rocksolid rotation of the motor pulley is far more critical on low mass platter designs.(just a tip for the ac motor of yr Lenco : use a mumetal shield iso alu and ground the shield)
I agree on regulation of the a.c. motor being harder to achieve,but I prefer it's brute force approach provided all else is up to par.
Both have pro's and con's of course.(Hang on folks we'll explain later on.)
As with most things:all depends on what you need and how you integrate it with the rest of the design.Belt and belt materials come to mind.
10/When I read yr. previous post I somehow thought you meant I had suggested it,which I didn't.
Here comes the more unconventional part:since I use a high mass primary platter, (remember I suggested a split design),this platter is going to be around 15 cm high,32cm diam.
Since my bearing housing is fixed on the plinth (going through it) and is relatively short but wide (roughly :bearing height 2.5 cm width of top 3 cm diam.) Actual shape of its top is the same as a simple round hat looked at from the top.The rim of the hat is only a few mm away from the plinth's top.
Actually the plith and it's function should not be overlooked either in view of system integration.It plays an important role.
Now I use this top to put my primary platter on (50 Kg of solid stainless steel)which has a recess in the center of 3cm diam. and 1 cm depth, as well making for intimate contact plus relatively large contact area (tight coupling is not what I want here)I achieve stabilty by weight and the overhang on the bottom.
You can well imagine that if I now attach the belt around 3 cm height from the bottom of the platter and use a good elastomer for belt material it is by no means possible to tilt the platter.(I invite you to try it even with you bare hands,it won't move.)
The choice of belt is another topic of debate,certainly not unimportant either.
Why else,you might ask do I want my bearing to sit this low?
Apart from the stabilty (both dynamic and static) I achieve also that my bearing ,which will always induce some chatter no matter what you do, is far enough removed from the surface that by the time it reaches my top platter (remember I use a split platter design)it will have absorbed and dissipated any spurious energy emanating from it in the high mass.
Whatever may still reach the top will not carry much energy.
Hope this has clarified some points under scrutiny.
Rgds,
TT
Peter,
Let's get constructive here.
I didn't like where it was going either and I surely wasn't the only one.
At least I get some reactions and have you sitting up listening attentively,dont'I?
From what I see,and I stated it before,every single participant has got some idea of what they want to achieve.
Unfortunately we can't address everyone's needs at the same time.
You take your bath in oil,someone else wants to float on air,me having to keep everything afloat.
What about poor Pedro?He started all this and what is he getting out of it?
Good thing he seems to be a very nice fellow.🙂 😀
Maybe you should all start a thread along the lines "My turntable,the way I want it."??
You could you know.Audio is not absolute science,if at all science.
Although a lot more science goes into it than you probably realize.
From what I gather,all in all you can't complain looking at all the previous posts attending your request🙄 ??
I ain't doing this for myself you know;been there, done that,thank you very much.
Not to mention the fact I made a living out of consulting work along these lines for fifteen years...Still complaining?
Come on,loosen up and next time you go away hook up that fancy laptop will you?
So here we go:
Look at the context and I'm sure you understand that I don't want to explain things for the sake of it.When required I will.
If anyone specifically asks for it and has a use for it too.
Ain't that grand?
Please read my latest post to Havoc.
The ludicrous part being discussing number 13.Superstition.
NOT your idea.
Reread without prejudice nor bias pls.
(I admit it was ambiguous) 🙁
Now we have all that out of harm's way, I assume you still want to know why I think the idea of the oilbath floater is not such a good idea ?
1/The idea has been brought forward in audio circles before and was pretty close to your first design picture bar the bearing.
The idea behind it was:
-to do away with the conventional bearing and to replace it with a frictionless one, in casu oil.(later on mercury was tried but still carried the same basic flaws and added some of its own.
*It was finally dismissed for the obvious reasons:
A turntable has to rotate it's platter and therefore need to have a solid point of reference.Several belt and pulley arrangements were tried but abandonded.The platter was still wandering about.
Other points against it were: oil is hygroscopic,tends to migrate to all kind of places you don't want it to,changes its viscosity and other characteristics over time,with heat and other climatic and domestic circumstances (notorious dust collector).In short it was out of control.
Come to think of it:some oil might get in contact with the belt as well causing slip and depending on the oil type used even attack it chemically.
-your idea adds a bearing.This negates the shear presence of the oilbath in the first place.
The oil you will have to use for your bearing will have to be the oil you use in the bath as well since they both merge.
Well,not necessarily.Still.
Bearing oil is usually specified by the bearing manufacturer,not much way for experimenting with different viscosities here either.
-your reasoning is that you want to dampen your platter that way.
*If your platter needs that much dampening than there is something seriously wrong with it.
Dampening should be done on the platter if needed not inbetween platter and support.
On top of that it will be heavily overdamped in a particular frequency range making for a flat,dead sound lacking life and sparkle.Try it out and report back to the forum if you like and if you have the chance to listen to a unipivot arm with and without dampening you will get some idea.
(The very same applies to the arm under scrutiny.If it behaves so badly it needs dampening than something does not compute.Vibrations aren't that easy you know.)
Since the oil layer will also provide a medium of travel for any bearing chatter,acoustic feedback from motor,not to mention the soundfield of the room you will effectively couple everything into your platter,into your record,into your cartridge...all this through a pass filter of some kind.😱
Then again you don't have to take my word for it.
Suck it and see.
Good luck with your project,😉
Peter,
Let's get constructive here.
I didn't like where it was going either and I surely wasn't the only one.
At least I get some reactions and have you sitting up listening attentively,dont'I?
From what I see,and I stated it before,every single participant has got some idea of what they want to achieve.
Unfortunately we can't address everyone's needs at the same time.
You take your bath in oil,someone else wants to float on air,me having to keep everything afloat.
What about poor Pedro?He started all this and what is he getting out of it?
Good thing he seems to be a very nice fellow.🙂 😀
Maybe you should all start a thread along the lines "My turntable,the way I want it."??
You could you know.Audio is not absolute science,if at all science.
Although a lot more science goes into it than you probably realize.
From what I gather,all in all you can't complain looking at all the previous posts attending your request🙄 ??
I ain't doing this for myself you know;been there, done that,thank you very much.
Not to mention the fact I made a living out of consulting work along these lines for fifteen years...Still complaining?
Come on,loosen up and next time you go away hook up that fancy laptop will you?
So here we go:
Look at the context and I'm sure you understand that I don't want to explain things for the sake of it.When required I will.
If anyone specifically asks for it and has a use for it too.
Ain't that grand?
Please read my latest post to Havoc.
The ludicrous part being discussing number 13.Superstition.
NOT your idea.
Reread without prejudice nor bias pls.
(I admit it was ambiguous) 🙁
Now we have all that out of harm's way, I assume you still want to know why I think the idea of the oilbath floater is not such a good idea ?
1/The idea has been brought forward in audio circles before and was pretty close to your first design picture bar the bearing.
The idea behind it was:
-to do away with the conventional bearing and to replace it with a frictionless one, in casu oil.(later on mercury was tried but still carried the same basic flaws and added some of its own.
*It was finally dismissed for the obvious reasons:
A turntable has to rotate it's platter and therefore need to have a solid point of reference.Several belt and pulley arrangements were tried but abandonded.The platter was still wandering about.
Other points against it were: oil is hygroscopic,tends to migrate to all kind of places you don't want it to,changes its viscosity and other characteristics over time,with heat and other climatic and domestic circumstances (notorious dust collector).In short it was out of control.
Come to think of it:some oil might get in contact with the belt as well causing slip and depending on the oil type used even attack it chemically.
-your idea adds a bearing.This negates the shear presence of the oilbath in the first place.
The oil you will have to use for your bearing will have to be the oil you use in the bath as well since they both merge.
Well,not necessarily.Still.
Bearing oil is usually specified by the bearing manufacturer,not much way for experimenting with different viscosities here either.
-your reasoning is that you want to dampen your platter that way.
*If your platter needs that much dampening than there is something seriously wrong with it.
Dampening should be done on the platter if needed not inbetween platter and support.
On top of that it will be heavily overdamped in a particular frequency range making for a flat,dead sound lacking life and sparkle.Try it out and report back to the forum if you like and if you have the chance to listen to a unipivot arm with and without dampening you will get some idea.
(The very same applies to the arm under scrutiny.If it behaves so badly it needs dampening than something does not compute.Vibrations aren't that easy you know.)
Since the oil layer will also provide a medium of travel for any bearing chatter,acoustic feedback from motor,not to mention the soundfield of the room you will effectively couple everything into your platter,into your record,into your cartridge...all this through a pass filter of some kind.😱
Then again you don't have to take my word for it.
Suck it and see.
Good luck with your project,😉
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