Analogue
Thanks very much for you input. I'm particularly interested in your deep edged Rega solution and modded bearing. If you have more information like how heavy it was, how it sounded and some drawing if possible.
I'm also interested in how the HW19 bearing and the wooden platter pan out.
Regards BT
Thanks very much for you input. I'm particularly interested in your deep edged Rega solution and modded bearing. If you have more information like how heavy it was, how it sounded and some drawing if possible.
I'm also interested in how the HW19 bearing and the wooden platter pan out.
Regards BT
OK….
First off, I do this just for a hobby so everything has to be easily funded in some way.
I have two Rega ‘bearing’ tables that I am working on, one for a friend using a standard Rega motor from a P5 and one for myself, I’m trying to make a direct drive turntable based on the Rega bearing/hub. However I have to clear out some of the items I’ve collected before I build any more. If you search for ‘Teres’ on Audiogon you will see two things I’m trying to clear out.
I’ve attached a sketch of the ‘Rega’ platter that I’m going to make out of the ¾” black acrylic that I have. I’m waiting to hold the P5 motor in my hand before I dimension the rest, but you will get the idea. It is slightly smaller OD than the Teres platter sketch. 11.6” is the diameter I use for the first groove of music on a 12” LP, so the thicker edge of the record will overhang slightly. The 12.25” dimension on the first sketch, matches the new VPI platter so that their outer ring weight could be used.
There was no science to the depth 4.5” except that in my eye it balances the width, it could be made deeper (I’ll see what it turns out to look like and may add another layer). 4.5” high allows a nice area inside to hide motor and control board etc. I’ll build a central pillar 6” or so in diameter so the platter appears to float in the air.
I have made slightly bigger platters out to 13.25” but then you’d have to be aware of the tonearm being used. And cost goes up as the yield goes down since normally material is available in multiples of 12”.
Style wise, I’ve been through my phase with the motor driving the outer diameter of the platter and things spread out across the top of the support…..I tend to prefer the mechanics out of site and use so a sub-platter. The P5 motor is 24volt and together with the Rega PSU provides switchable speeds, so no lifting of the platter.
There are obviously other bearings/hubs out there Thorens, Linn etc. that may be more suitable, scalped from old turntables.….Its just what I have used.
As I said I used a Deepgroove rega hub before, I may use the Groovetracer this time it looks finely made. The bearing housing was made from brass, similar configuration to the Rega, except it was about 30mm OD, threaded and had a large flange at the top so I had something to tighten the nut against. The ability of the bearing to ‘ground’ into the plinth makes a big difference I think. A platter like this is about 12lbs/5kg, I was planning to only lightly mass load it, filling more to dampen it slightly. Does anyone know it the P9 with its heavy platter uses a different bearing than the p3’s etc? I’d be interested to know as I might look into that as an alternative.
Acrylic platters have a similar sound, read some of the online reviews of Teres tables or Euro Labs/Scheu. I think the Teres bearing with its higher drag design seems to give more stability to the sound than the Rega design, but I also like the Michell bearing a lot, if it is grounded well to strong plinth.
I’ve gone away from the pure Acrylic platter sound and use a Boston Mat 1 (carbon) on my table, this combination seems a good compromise. I think that PVC is somewhere between Acrylic and this combination……. As a material PVC might get used more if it was not for the name…
There are other reasons I use this particular carbon mat. The most important is I like to clamp the record to the platter, using a thin washer at the centre. With the carbon mat I put the washer underneath it. The 3mm thick mat then curves with the record as the clamp is tightened, so the record is supported across its width. This is not the way the manufacturer intended it to be used but it works for me.
Seems like a long reply around various subjects, but I hope its good food for thought.
First off, I do this just for a hobby so everything has to be easily funded in some way.
I have two Rega ‘bearing’ tables that I am working on, one for a friend using a standard Rega motor from a P5 and one for myself, I’m trying to make a direct drive turntable based on the Rega bearing/hub. However I have to clear out some of the items I’ve collected before I build any more. If you search for ‘Teres’ on Audiogon you will see two things I’m trying to clear out.
I’ve attached a sketch of the ‘Rega’ platter that I’m going to make out of the ¾” black acrylic that I have. I’m waiting to hold the P5 motor in my hand before I dimension the rest, but you will get the idea. It is slightly smaller OD than the Teres platter sketch. 11.6” is the diameter I use for the first groove of music on a 12” LP, so the thicker edge of the record will overhang slightly. The 12.25” dimension on the first sketch, matches the new VPI platter so that their outer ring weight could be used.
There was no science to the depth 4.5” except that in my eye it balances the width, it could be made deeper (I’ll see what it turns out to look like and may add another layer). 4.5” high allows a nice area inside to hide motor and control board etc. I’ll build a central pillar 6” or so in diameter so the platter appears to float in the air.
I have made slightly bigger platters out to 13.25” but then you’d have to be aware of the tonearm being used. And cost goes up as the yield goes down since normally material is available in multiples of 12”.
Style wise, I’ve been through my phase with the motor driving the outer diameter of the platter and things spread out across the top of the support…..I tend to prefer the mechanics out of site and use so a sub-platter. The P5 motor is 24volt and together with the Rega PSU provides switchable speeds, so no lifting of the platter.
There are obviously other bearings/hubs out there Thorens, Linn etc. that may be more suitable, scalped from old turntables.….Its just what I have used.
As I said I used a Deepgroove rega hub before, I may use the Groovetracer this time it looks finely made. The bearing housing was made from brass, similar configuration to the Rega, except it was about 30mm OD, threaded and had a large flange at the top so I had something to tighten the nut against. The ability of the bearing to ‘ground’ into the plinth makes a big difference I think. A platter like this is about 12lbs/5kg, I was planning to only lightly mass load it, filling more to dampen it slightly. Does anyone know it the P9 with its heavy platter uses a different bearing than the p3’s etc? I’d be interested to know as I might look into that as an alternative.
Acrylic platters have a similar sound, read some of the online reviews of Teres tables or Euro Labs/Scheu. I think the Teres bearing with its higher drag design seems to give more stability to the sound than the Rega design, but I also like the Michell bearing a lot, if it is grounded well to strong plinth.
I’ve gone away from the pure Acrylic platter sound and use a Boston Mat 1 (carbon) on my table, this combination seems a good compromise. I think that PVC is somewhere between Acrylic and this combination……. As a material PVC might get used more if it was not for the name…
There are other reasons I use this particular carbon mat. The most important is I like to clamp the record to the platter, using a thin washer at the centre. With the carbon mat I put the washer underneath it. The 3mm thick mat then curves with the record as the clamp is tightened, so the record is supported across its width. This is not the way the manufacturer intended it to be used but it works for me.
Seems like a long reply around various subjects, but I hope its good food for thought.
P9 bearing
The P9 bearing is made especially for the P9. It is a thing of beauty! And expensive! I was once told that the bearings for the p 2,3,etc were the best that could be made for the price, but the bearing for the p9 was simply the best that they knew how to make! Even so I would not recommend more than 5 kg load. (I believe a standard p9 platter is 4.5 kg)
The P9 bearing is made especially for the P9. It is a thing of beauty! And expensive! I was once told that the bearings for the p 2,3,etc were the best that could be made for the price, but the bearing for the p9 was simply the best that they knew how to make! Even so I would not recommend more than 5 kg load. (I believe a standard p9 platter is 4.5 kg)
Deckman,
Thanks for the info on the P9.
As you said in earlier post, P3 bearing limit of 3.5 kgs, my prior attempt must have been about 4-5kg with the mass down low…… I remember the first time of looking at the Rega bearing shaft and thinking it was down sized for cost (spindly maybe an apt word). I’ll think more about taking out additional material from inside of the platter this time as this won’t change inertia much.
At first I did not do a long look at bearings I was given Rega parts “can you build me ‘something’ with these?” and I could get the matched motors/pulleys and upgraded hubs for a reasonable cost and availability, with few questions. The distributor in the US that I talk too is interested in the ‘projects’ I doing, rather than being concerned about my ‘re-purposing’.
Maybe the start of a new thread should discuss merits/availability of bearings.
I definitely gravitate to using a heavy platter, the sound comes above a more solid background. But I’ll reserve the 30lb (13kg?) platter for use with the Teres bearing which was designed for it.
By the way nice pictures that you’ve attached to earlier posts Deckman beautiful work! are these for your own use or made to order?
Thanks for the info on the P9.
As you said in earlier post, P3 bearing limit of 3.5 kgs, my prior attempt must have been about 4-5kg with the mass down low…… I remember the first time of looking at the Rega bearing shaft and thinking it was down sized for cost (spindly maybe an apt word). I’ll think more about taking out additional material from inside of the platter this time as this won’t change inertia much.
At first I did not do a long look at bearings I was given Rega parts “can you build me ‘something’ with these?” and I could get the matched motors/pulleys and upgraded hubs for a reasonable cost and availability, with few questions. The distributor in the US that I talk too is interested in the ‘projects’ I doing, rather than being concerned about my ‘re-purposing’.
Maybe the start of a new thread should discuss merits/availability of bearings.
I definitely gravitate to using a heavy platter, the sound comes above a more solid background. But I’ll reserve the 30lb (13kg?) platter for use with the Teres bearing which was designed for it.
By the way nice pictures that you’ve attached to earlier posts Deckman beautiful work! are these for your own use or made to order?
Bearings, a new start?
Analogue, yes I think starting new thread for bearings would be worthwhile. They are a key element of the turntable and not easy for DIY manufacture. By the way, the P3 bearing is one of the most widely used bearings in the world. The shaft is actually the needle from a large needle roller bearing, clever eh!
Like you, I have mostly used heavier platters on solid decks, but more recently I've been experimenting with low mass sub decks and platters on high mass (granite) main decks. Using very high-quality crystal locked speed controls and AC synchronous motors. The idea being the less mass you have, the less there is to store energy, and the less work motors have to do to maintain speed stability. Early results are promising but I'm using some fairly exotic materials (Titanium and magnesium aluminium) and I have a lot more development to do before I can say that it has been a success or not.
Regarding my stuff, I'm glad you like the pictures. I produce a very small number of bespoke turntables and loudspeakers to order. I've been doing this for many years, and I've never produced the same thing twice! The research into a ‘low mass deck’ is to support a commission from one of my more affluent customers, hence the Titanium! And yes, I do know how lucky I am to be paid to play!
Analogue, yes I think starting new thread for bearings would be worthwhile. They are a key element of the turntable and not easy for DIY manufacture. By the way, the P3 bearing is one of the most widely used bearings in the world. The shaft is actually the needle from a large needle roller bearing, clever eh!
Like you, I have mostly used heavier platters on solid decks, but more recently I've been experimenting with low mass sub decks and platters on high mass (granite) main decks. Using very high-quality crystal locked speed controls and AC synchronous motors. The idea being the less mass you have, the less there is to store energy, and the less work motors have to do to maintain speed stability. Early results are promising but I'm using some fairly exotic materials (Titanium and magnesium aluminium) and I have a lot more development to do before I can say that it has been a success or not.
Regarding my stuff, I'm glad you like the pictures. I produce a very small number of bespoke turntables and loudspeakers to order. I've been doing this for many years, and I've never produced the same thing twice! The research into a ‘low mass deck’ is to support a commission from one of my more affluent customers, hence the Titanium! And yes, I do know how lucky I am to be paid to play!
Attachments
Well certainly if you have to work for a living getting paid to do something you like is on the top of my list………!! And if your affluent customers know any affluent potential customers in the US then please give them my name!
Interesting commission too, good luck. If you need any timezone interfaces to state side manufactures of stuff (http://www.thingap.com/ for example) or anything let me know.
A turntable is very obviously a musical instrument with a sonic signature resulting from the tradeoffs and compromises made. My ideas at the moment are going towards building a heavy plastic platter with direct drive and though I’m having to learn the electronics (so it is taking time to experiment), I choose to think that a heavy platter will sound better. …..I got in to building Turntables as a roll over from modifying/building Tonearms, so I consider turntables as the ‘heavy engineering’ part of the system anyway.
But then, if a piece of foam between the cartridge and the tonearm (the isolator-musicman) can ruffle the doctrine of “rigidity at all cost” who’s to say.
So going back to the thread topic I think PVC or Acrylic are safe bets to start making a platter from. Delrin, though I’ve never heard of its use, might also be a good starting point pulled this off Wikipedia….
“Another recent use for Delrin is in the manufacturing of Irish flutes (traditionally made of wood) and tin whistles (traditionally made of metal). Delrin flutes sound similar or identical to wooden flutes but have none of the shrinkage or cracking issues usually associated with wooden instruments”.
Anything that appears to have this natural frequency characteristic would have the potential to make a reasonable platter with little experimentation. If you can handle the material before you buy....try hitting it and see how it sounds.
Regards
Interesting commission too, good luck. If you need any timezone interfaces to state side manufactures of stuff (http://www.thingap.com/ for example) or anything let me know.
A turntable is very obviously a musical instrument with a sonic signature resulting from the tradeoffs and compromises made. My ideas at the moment are going towards building a heavy plastic platter with direct drive and though I’m having to learn the electronics (so it is taking time to experiment), I choose to think that a heavy platter will sound better. …..I got in to building Turntables as a roll over from modifying/building Tonearms, so I consider turntables as the ‘heavy engineering’ part of the system anyway.
But then, if a piece of foam between the cartridge and the tonearm (the isolator-musicman) can ruffle the doctrine of “rigidity at all cost” who’s to say.
So going back to the thread topic I think PVC or Acrylic are safe bets to start making a platter from. Delrin, though I’ve never heard of its use, might also be a good starting point pulled this off Wikipedia….
“Another recent use for Delrin is in the manufacturing of Irish flutes (traditionally made of wood) and tin whistles (traditionally made of metal). Delrin flutes sound similar or identical to wooden flutes but have none of the shrinkage or cracking issues usually associated with wooden instruments”.
Anything that appears to have this natural frequency characteristic would have the potential to make a reasonable platter with little experimentation. If you can handle the material before you buy....try hitting it and see how it sounds.
Regards
Re: P9 bearing
The P9 subplatter has 2 obvious differences over the other Rega offerings. Firstly, It has an aluminum hub with 3 raised areas machined into it. Secondly, The bearing axle or shaft has a spherical radius machined into the bottom of it to eliminate the use of a ball bearing. Whether this is superior to the standard ball bearing feature, I don't know but I would think vibration would more easily be transmitted through the integral ball design.
Deckman said:
The P9 subplatter has 2 obvious differences over the other Rega offerings. Firstly, It has an aluminum hub with 3 raised areas machined into it. Secondly, The bearing axle or shaft has a spherical radius machined into the bottom of it to eliminate the use of a ball bearing. Whether this is superior to the standard ball bearing feature, I don't know but I would think vibration would more easily be transmitted through the integral ball design.
Platter in progress
Just though to take a few 'in progress' pictures of a platter made for the Teres bearing (Diagram posted earlier).
Photos show the two sub assemblies first part with 16 holes and second part is simple plate to cover after filling. Outside diameter will be finished after filling and assembly.
The dimensions are 12.25 OD and ID's to fit bearing. Depth at the moment is 4 layers of 0.75" acrylic ~3" which is slightly deeper than Teres bearig designed for, but I will adjust plinth height accordingly. Weight before filling 13lbs.
I'm still experimenting with how to make these in the easiest way. Next time I will make as one piece and will find a different way to add the fill into the cavities.
This time I'm using a DC motor without speed sensing so did not apply the Teres radial sensor markings.
Just though to take a few 'in progress' pictures of a platter made for the Teres bearing (Diagram posted earlier).
Photos show the two sub assemblies first part with 16 holes and second part is simple plate to cover after filling. Outside diameter will be finished after filling and assembly.
The dimensions are 12.25 OD and ID's to fit bearing. Depth at the moment is 4 layers of 0.75" acrylic ~3" which is slightly deeper than Teres bearig designed for, but I will adjust plinth height accordingly. Weight before filling 13lbs.
I'm still experimenting with how to make these in the easiest way. Next time I will make as one piece and will find a different way to add the fill into the cavities.
This time I'm using a DC motor without speed sensing so did not apply the Teres radial sensor markings.
Attachments
I have managed to source a slab of perspex 45mm thick and have sourced a bearing for the job. I would like some help on dimensions.
1) What diameter and depth for label recess.
2) Minimum distance to have the spindle protrude from the top of the platter.(Will be using so sort of weight)
3) Maximum platter diameter possible when using 9" arm. The slab is 350mm wide. Though will probable make a 12" arm.
Finally I'm interested in sourcing a brushless DC motor like the Scheu one. If anyone knows of a cheap source I would be grateful.
Regards BT
1) What diameter and depth for label recess.
2) Minimum distance to have the spindle protrude from the top of the platter.(Will be using so sort of weight)
3) Maximum platter diameter possible when using 9" arm. The slab is 350mm wide. Though will probable make a 12" arm.
Finally I'm interested in sourcing a brushless DC motor like the Scheu one. If anyone knows of a cheap source I would be grateful.
Regards BT
Hi,
the flat part of the platter should be about 294mm od and 105mm id.
The overall platter diameter can and should be larger than the flat part. I would go to 310mm or so.
The outer part (from 294 to 310) needs to be recessed about 0.5mm to miss the lip at the outer rim of thin albums. Albums prior to 1974/5 do not have this plastic saving lip.
The inner recess is about 0.3 to 0.5mm deep to miss the label area. Depth is not critical provided it is not too shallow.
I would machine a plain support area around the spindle to centre the album, but top this off with a coarse thread to allow later fitting of a screw down record clamp.
Inertia is proportional to the fourth power of diameter. Small increases in diameter create substantial increases in inertia. If you want a high inertia platter then increase the overall diameter to well above 310mm.
the flat part of the platter should be about 294mm od and 105mm id.
The overall platter diameter can and should be larger than the flat part. I would go to 310mm or so.
The outer part (from 294 to 310) needs to be recessed about 0.5mm to miss the lip at the outer rim of thin albums. Albums prior to 1974/5 do not have this plastic saving lip.
The inner recess is about 0.3 to 0.5mm deep to miss the label area. Depth is not critical provided it is not too shallow.
I would machine a plain support area around the spindle to centre the album, but top this off with a coarse thread to allow later fitting of a screw down record clamp.
Inertia is proportional to the fourth power of diameter. Small increases in diameter create substantial increases in inertia. If you want a high inertia platter then increase the overall diameter to well above 310mm.
I would love to tell you more but there's not much more to tell! I found the vinyl slab in the workshop where I worked many years ago at the same time as deciding I could make my own TT. I "eyeball" engineered the lot, no drawings at all. The bearing was lapped to size and is an inverted design with a ball bearing and hardened insert in the shaft.
Its no work of art but it works great and I have the satisfaction of having done it myself.
Paul
Edit: forgot to say its based on more mass is better and is very heavy!
Its no work of art but it works great and I have the satisfaction of having done it myself.
Paul
Edit: forgot to say its based on more mass is better and is very heavy!
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