Platter material
I have made platters from all sorts of materials. The choice of material depends on number of factors.
· Is it a suspended deck? If so you need to get the mass right so as not to affect the suspension.
· Do you have closed loop speed control? Or do you need to rely on the mass of platter for speed stability.
· You need to consider the materials used in the construction of the deck itself. The materials you use will influence the sound. Generally speaking a turntable made completely of granite will sound, like the material, hard, clean, fast. A suspended deck made from wood will sound more organic. You get the idea.
· How do you intend to drive the platter? Will you use a sub platter, Rega style, or drive the platter rim.
· Will you machine the platter yourself? You will need a fairly large lathe, probably with the gap bed to swing 300 mm.
Cast acrylic is increasingly popular as it is relatively easy to machine, does not cost the earth and provides a good interface with the record.
I have made platters from all sorts of materials. The choice of material depends on number of factors.
· Is it a suspended deck? If so you need to get the mass right so as not to affect the suspension.
· Do you have closed loop speed control? Or do you need to rely on the mass of platter for speed stability.
· You need to consider the materials used in the construction of the deck itself. The materials you use will influence the sound. Generally speaking a turntable made completely of granite will sound, like the material, hard, clean, fast. A suspended deck made from wood will sound more organic. You get the idea.
· How do you intend to drive the platter? Will you use a sub platter, Rega style, or drive the platter rim.
· Will you machine the platter yourself? You will need a fairly large lathe, probably with the gap bed to swing 300 mm.
Cast acrylic is increasingly popular as it is relatively easy to machine, does not cost the earth and provides a good interface with the record.
Attachments
Hi Deckman,
What I'm trying to achieve is to create as good a deck for as little as possible. I intend to keep things as simple as possible and try to use things which can be adapted. Probably no suspension, no subplatter and DC motor without speed control. I do not intend to machine the components myself, so will need to ask around for help.
I will need to source a good bearing from somewhere, again cheaply.
For the plinth/subchassis could be granite or aluminium, for the platter could be acrylic aluminium. All dependant on cost/tonal quality. Have found wood a bit dull in the past.
still open minded.
Regards BT
What I'm trying to achieve is to create as good a deck for as little as possible. I intend to keep things as simple as possible and try to use things which can be adapted. Probably no suspension, no subplatter and DC motor without speed control. I do not intend to machine the components myself, so will need to ask around for help.
I will need to source a good bearing from somewhere, again cheaply.
For the plinth/subchassis could be granite or aluminium, for the platter could be acrylic aluminium. All dependant on cost/tonal quality. Have found wood a bit dull in the past.
still open minded.
Regards BT
Where to start
OK, it may be easier to start from a different place and say what is your total budget for this project, then work back to the main component costs. To give you some idea of costs, a half decent main bearing is the Rega P3 (available through the moth group for around £18+p&p) you would be amazed at how many manufacturers use this bearing. A slab of clear cast acrylic 50mm thick is around £50, but because it has to be machined on all faces this could be the most expensive element. £50 - £150. Then it has to be polished, you can do it by hand but it takes ages and its hard work.
I use a lot of acrylic in my turntables. The most popular design at present is the ‘plastic fantastic’ (over 12 kg of acrylic) it sounds fast, detailed and clean. About as far away from the nice ‘warm’ analogue sound as you can get!
I have made decks from granite (Black Zimbabwe granite is best for this) they sound fantastic but we're talking ‘cost no object’ if you're on a tight budget I would go for an AC motor driving a sub platter. You can get the motors from radio spares (RS Stock no: 441-0423) just over £30.
OK, it may be easier to start from a different place and say what is your total budget for this project, then work back to the main component costs. To give you some idea of costs, a half decent main bearing is the Rega P3 (available through the moth group for around £18+p&p) you would be amazed at how many manufacturers use this bearing. A slab of clear cast acrylic 50mm thick is around £50, but because it has to be machined on all faces this could be the most expensive element. £50 - £150. Then it has to be polished, you can do it by hand but it takes ages and its hard work.
I use a lot of acrylic in my turntables. The most popular design at present is the ‘plastic fantastic’ (over 12 kg of acrylic) it sounds fast, detailed and clean. About as far away from the nice ‘warm’ analogue sound as you can get!
I have made decks from granite (Black Zimbabwe granite is best for this) they sound fantastic but we're talking ‘cost no object’ if you're on a tight budget I would go for an AC motor driving a sub platter. You can get the motors from radio spares (RS Stock no: 441-0423) just over £30.
just curious
Would it not be the most logical choice of platter material to use vinyl? Used records could be a very inexpensive source melted down to liquid and cast into a form then machined true. Would seem that as an interface between the record and the platter this would be ideal. For greater mass one could also have a look at VCT floor tile (vinyl composite tile) these are the ones that are about 1/8 inch thick by 9" or 12" square. Lots of mass and very dead. Would be interested to hear comments. Best regards Moray James.
Would it not be the most logical choice of platter material to use vinyl? Used records could be a very inexpensive source melted down to liquid and cast into a form then machined true. Would seem that as an interface between the record and the platter this would be ideal. For greater mass one could also have a look at VCT floor tile (vinyl composite tile) these are the ones that are about 1/8 inch thick by 9" or 12" square. Lots of mass and very dead. Would be interested to hear comments. Best regards Moray James.
Hi Moray,
Melting records sounds messy but if anyone has a method I would consider it. I might look into the tiles though.
Deckman,
It would be difficult to suggest a budget, but let's say £500.
As for the rega bearing, can it be used without the sub-patter, would it cope with say 80mm of acrylic say or 50mm of Aluminium?
What have you used in the deck show and other decks?
regards BT
Melting records sounds messy but if anyone has a method I would consider it. I might look into the tiles though.
Deckman,
It would be difficult to suggest a budget, but let's say £500.
As for the rega bearing, can it be used without the sub-patter, would it cope with say 80mm of acrylic say or 50mm of Aluminium?
What have you used in the deck show and other decks?
regards BT
Bearings and stuff
I guess the Rega bearing is good for about 3 1/2 kg, possibly more but you will have increased wear. There are ways to increase its load carrying capability using a better quality ball bearing and PTFE slugs, but I don't think it will meet your requirements. Your probably looking at supporting a load of around 4,5-5,5 kg and that means a specialist bearing. You may have difficulty getting any of the mainstream manufacturers to supply you. You could try origin live, http://www.originlive.com Another option is to buy an old deck, something like a ‘system deck’ the bearing in this deck is massively over engineered and will last forever. There are places around the world that supply turntable kits. I have my bearings made for me, they are made one at a time and cost just over £250 each!
The deck shown uses 40 mm thick clear cast acrylic. Don't discount cheaper materials like MDF.
I guess the Rega bearing is good for about 3 1/2 kg, possibly more but you will have increased wear. There are ways to increase its load carrying capability using a better quality ball bearing and PTFE slugs, but I don't think it will meet your requirements. Your probably looking at supporting a load of around 4,5-5,5 kg and that means a specialist bearing. You may have difficulty getting any of the mainstream manufacturers to supply you. You could try origin live, http://www.originlive.com Another option is to buy an old deck, something like a ‘system deck’ the bearing in this deck is massively over engineered and will last forever. There are places around the world that supply turntable kits. I have my bearings made for me, they are made one at a time and cost just over £250 each!
The deck shown uses 40 mm thick clear cast acrylic. Don't discount cheaper materials like MDF.
Attachments
Two things worth keeping in mind: resonance and weight. Materials like aluminum will ring unless sandwiched with something to counter it. Good, inert materials are stone, concrete, and certain plastics.
The second thing to keep in mind is the weight. If you get your platter over 18 lbs or so, mechanical bearing noise will begin to be a problem. Most platters weigh less than this, though, and designers wishing to go heavier often resort to air bearings.
-Karl
The second thing to keep in mind is the weight. If you get your platter over 18 lbs or so, mechanical bearing noise will begin to be a problem. Most platters weigh less than this, though, and designers wishing to go heavier often resort to air bearings.
-Karl
Gyro Mass
If you wanted to go with the less expensive Regga bearing you coucl consider a lighter platter with "flywheel" mass added to the outside edge of the platter as Mitchell has done on thier "Gyro Deck". Other companies have also gone this direction. This is a good compromise. Regards Moray James.
If you wanted to go with the less expensive Regga bearing you coucl consider a lighter platter with "flywheel" mass added to the outside edge of the platter as Mitchell has done on thier "Gyro Deck". Other companies have also gone this direction. This is a good compromise. Regards Moray James.
again..(hey Moray how ya been?)..
well the DIY table rears it's ugly head again..!
Ok, not ugly.
Q: Toseland, why are you wanting to build? What is the motive? If you want a good table available inexpensively, look at used. You don't state your intended budget. Are you wanting the performance of say a Delphi (sorry for the obvious canuck plug, I can't help myself), for the price of a BPPOS, then nope. and if your budget is say perhaps 50-60 % of a Delphi (or whatever your dream table is), then you may well be better served by finding a used one. If the exercise is to prove you can, then go for it.
someplace I recall a Harley Davidson valve/guide pair that had been used. I had a custom brg made and it has cost me way over $300 USD. Apparently a brg from a Technics SL1200 can be purchased new for $30 USD as well (and knowing that now, that is perhaps the way that I would go).
well the DIY table rears it's ugly head again..!
Ok, not ugly.
Q: Toseland, why are you wanting to build? What is the motive? If you want a good table available inexpensively, look at used. You don't state your intended budget. Are you wanting the performance of say a Delphi (sorry for the obvious canuck plug, I can't help myself), for the price of a BPPOS, then nope. and if your budget is say perhaps 50-60 % of a Delphi (or whatever your dream table is), then you may well be better served by finding a used one. If the exercise is to prove you can, then go for it.
someplace I recall a Harley Davidson valve/guide pair that had been used. I had a custom brg made and it has cost me way over $300 USD. Apparently a brg from a Technics SL1200 can be purchased new for $30 USD as well (and knowing that now, that is perhaps the way that I would go).
Nanook,
I currently have a Logik DM101, a Linn type turntable. I've looked at used turntable but good ones still fetch very good money. If i look at the sort of designs that are around now and cost the materials, I start to feel that building should be considered.
I could by a bearing from Scheu and the platter and the motor if I wanted, but the object is to try to get the best for the least. So sourcing components which were intended for an other purpose which are cheap but do the job is the sort of process I'm interested in.
I intend to keep thing as simple as possible.
My first question was about materials as I'd found some 50mm Delrin for a reasonable price.
My brother has a Delphi 3 and as far as I can see has a aluminium platter and subchassis. Lots of people use acrylic including Mark Baker of Origin Live. I've heard the Resolution and it works very well and now he has used acrylic for the Sovereign.
So 2 of 3 inches of acrylic would probably me ok, if I could source it and at a reasonable price.
Thanks everyone for your input.
Regards BT
I currently have a Logik DM101, a Linn type turntable. I've looked at used turntable but good ones still fetch very good money. If i look at the sort of designs that are around now and cost the materials, I start to feel that building should be considered.
I could by a bearing from Scheu and the platter and the motor if I wanted, but the object is to try to get the best for the least. So sourcing components which were intended for an other purpose which are cheap but do the job is the sort of process I'm interested in.
I intend to keep thing as simple as possible.
My first question was about materials as I'd found some 50mm Delrin for a reasonable price.
My brother has a Delphi 3 and as far as I can see has a aluminium platter and subchassis. Lots of people use acrylic including Mark Baker of Origin Live. I've heard the Resolution and it works very well and now he has used acrylic for the Sovereign.
So 2 of 3 inches of acrylic would probably me ok, if I could source it and at a reasonable price.
Thanks everyone for your input.
Regards BT
Have you considered?
using the parts from your Logik DM101 to build a new table? You could cast Acrylic resen into the bottom of the platter and as long as you have it dead level so too will the cast resin. If you wanted you could also cast a layer of resin onto the top side of the platter. A visit to the local plastic machine shop specialists would true the platter up and level the top playing surface including a small cutout for the lable. If you are level when you cast and you have a shop spin the disk true on a lath then I doubt that you will have to worry about balancing the platter after turning it. You will have cut your parts cost right down to a minimum. Regards Moray James.
using the parts from your Logik DM101 to build a new table? You could cast Acrylic resen into the bottom of the platter and as long as you have it dead level so too will the cast resin. If you wanted you could also cast a layer of resin onto the top side of the platter. A visit to the local plastic machine shop specialists would true the platter up and level the top playing surface including a small cutout for the lable. If you are level when you cast and you have a shop spin the disk true on a lath then I doubt that you will have to worry about balancing the platter after turning it. You will have cut your parts cost right down to a minimum. Regards Moray James.
toseland, what is good?
ok, so the Logic is not good enough, but what is?
As far as unconventional materials, the idea of a valve guide, ball bearing and valve from a Harley certainly would fit the bill. (is that the Altmann/joke/no joke turntable platter?). Other items could be a hardened steel shaft (a drill bit) , a suitable tapered ball or roller bearing, etc..self centering
Even if 3" thick acrylic is available, you'd be suprised at how much cheaper 5 or 6 1/2" acrylic costs and it can be glued up with methylene chloride (use the water thin stuff). provide enough so that it will flow and completely fill any void between sheets and apply pressure, it is almost instant. Do that to make up the thickness, and have that machined--don't forget the top piece should be machined so that a label fits "into" the acrylic top layer.
Brooks Berdan(?) I think used to make platter mats for Oracle out of Delrin, as well as Delrin clamps..I made one out of 6 mm acrylic to replace the "Groove" Isolator" that came stock on my Oracle to good effect.
Or use a bunch of really bad cheezy albums glued up.
ok, so the Logic is not good enough, but what is?
As far as unconventional materials, the idea of a valve guide, ball bearing and valve from a Harley certainly would fit the bill. (is that the Altmann/joke/no joke turntable platter?). Other items could be a hardened steel shaft (a drill bit) , a suitable tapered ball or roller bearing, etc..self centering
Even if 3" thick acrylic is available, you'd be suprised at how much cheaper 5 or 6 1/2" acrylic costs and it can be glued up with methylene chloride (use the water thin stuff). provide enough so that it will flow and completely fill any void between sheets and apply pressure, it is almost instant. Do that to make up the thickness, and have that machined--don't forget the top piece should be machined so that a label fits "into" the acrylic top layer.
Brooks Berdan(?) I think used to make platter mats for Oracle out of Delrin, as well as Delrin clamps..I made one out of 6 mm acrylic to replace the "Groove" Isolator" that came stock on my Oracle to good effect.
Or use a bunch of really bad cheezy albums glued up.
acrylic sheets..
check the price of 3" sheet vs. say, 1/2" sheet and then you figure it out. I haven't priced it but 12"X12" "offcuts" may be available as scrap, and then, yes very cheap. Glue them up. Once glued, then drill a centre "pilot hole". Place the whole stack of them on a band saw work surface , locate a pin 6" away from the blade (perpendicular to the cutting edge of the band saw), and rotate the stack. End result: inexpensive, 3 1/2" thick plater, circular, with a pilot hole. Make sure you cut slowly though. once done the edges can be sanded smooth. Frosted edges, clear top and bottom, almost all DIY.
I'm certainly no fabrication expert (or an expert at all) but it seems that this should work. Ask the pros if this would work. I think it would.
check the price of 3" sheet vs. say, 1/2" sheet and then you figure it out. I haven't priced it but 12"X12" "offcuts" may be available as scrap, and then, yes very cheap. Glue them up. Once glued, then drill a centre "pilot hole". Place the whole stack of them on a band saw work surface , locate a pin 6" away from the blade (perpendicular to the cutting edge of the band saw), and rotate the stack. End result: inexpensive, 3 1/2" thick plater, circular, with a pilot hole. Make sure you cut slowly though. once done the edges can be sanded smooth. Frosted edges, clear top and bottom, almost all DIY.
I'm certainly no fabrication expert (or an expert at all) but it seems that this should work. Ask the pros if this would work. I think it would.
Hi,
have you thought of, discarded even, the idea of profiling the top surface of the platter to pull the record down into a slightly curved (cupped) shape?
The centre fixing needs to be quite tight to provide the pull down force.
One manufacturer did it a little differently.
They added a centre high point and pushed down just inside the innner grooves forcing the record playing surface into a cup shape. This required less shaping (none?) of the platter top.
have you thought of, discarded even, the idea of profiling the top surface of the platter to pull the record down into a slightly curved (cupped) shape?
The centre fixing needs to be quite tight to provide the pull down force.
One manufacturer did it a little differently.
They added a centre high point and pushed down just inside the innner grooves forcing the record playing surface into a cup shape. This required less shaping (none?) of the platter top.
I use a townsend rock turntable.
On that turntable the designer, max townshend, simply added a 2cm diameter by 2mm thick acrylic washer around the centre spindle. The record sits on the washer and that raises the record above the platter by 2mm. The record clamp then screws down on to the record and pushes the record into a concave shape untul the record is in firm contact with the platter.
This is a simple arrangement and allows the platter top surface, and the record, to remain flat - which I think is better for playing the record and should make the platter cheaper to manufacture.
Don
On that turntable the designer, max townshend, simply added a 2cm diameter by 2mm thick acrylic washer around the centre spindle. The record sits on the washer and that raises the record above the platter by 2mm. The record clamp then screws down on to the record and pushes the record into a concave shape untul the record is in firm contact with the platter.
This is a simple arrangement and allows the platter top surface, and the record, to remain flat - which I think is better for playing the record and should make the platter cheaper to manufacture.
Don
Hi AMV8,
is the Townsend Rock platter FLAT?
Have you put a straight edge across it? and measured it?
I have not got one nor never seen one so I am genuinely asking.
What prompts my enquiry is thinking about the shape the record will flex into when pulled down by the Tonwsend method. I do not believe that the record underside will be flat and if good contact is required over the majority of the surface then the profile on the platter should match the cupped shape of the record. I would not be surprised to find a depression only 1mm to 2mm deep at the inner groove location.
is the Townsend Rock platter FLAT?
Have you put a straight edge across it? and measured it?
I have not got one nor never seen one so I am genuinely asking.
What prompts my enquiry is thinking about the shape the record will flex into when pulled down by the Tonwsend method. I do not believe that the record underside will be flat and if good contact is required over the majority of the surface then the profile on the platter should match the cupped shape of the record. I would not be surprised to find a depression only 1mm to 2mm deep at the inner groove location.
In my recollection of my Rock Mk2 black platter was slightly concave (higher at the edge). But I use flat platters now with the central washer and clamp to pull it down. All things being equal you want the top surface of the record to be absolutely level, but its hard to predict how each record thickness varies and all the other parameters that might change.
I have just made a platter to fit a Teres (www.teresaudio.com), bearing the platter was made from ¾” black acrylic. As has been mentioned a layered assembly is much cheaper than buying a chunk 3” thick. It is diamond finished (glossy) and has 16 cavities drilled for mass loading. This weighs over 25lbs. I estimate cost would be about $250 all told with filling etc. (see diagram).
I have loaded platters with one of three things; lead shot as in the Teres Platter, Tungsten Powder (which couples better to the acrylic and gives more damping. Thirdly I have a home brew of rubber/lead/Epoxy that I think simulates the RDC material in the Clearlight products.
Each makes the Acrylic sound different.
I have made other platters, Acrylic is fast, PVC is nice also (see Galibier Design platters) and their talk.
I have not done as much experimenting with PVC but I have mass loaded with lead shot.
I usually buy bearings rather than have special made, that way you can get replacements. Either the Teres ($295 standard shaft on ball), Michell (Gyrodec, $249 inverted ball) or I have just ordered some VPI (HW19 NOS for $100 standard shaft and ball) I’ll see how they sound.
I was also asked to make a heavy platter for a Rega bearing. I made the platter about 5” deep at the edge, 15mm across the hub, used a ruby ball/Teflon thrust pad/aluminum hub (Deepgroove). Using a deep platter I though would reduce the side load on the platter bearing. I did have the brass part of the bearing made for it, because I wanted more mass than the standard Rega item, but I did not add any bushes. The standard Rega part is $45 so getting one made was the same order of cost.
My latest platter adventure is going to be a stabilized wood product, I’ve been asked for one by a friend. I’m interested to see how this compares to the Acrylic and the Teres wood platter that I can get a listen too on occasion.
Hope that’s of interest.
I have just made a platter to fit a Teres (www.teresaudio.com), bearing the platter was made from ¾” black acrylic. As has been mentioned a layered assembly is much cheaper than buying a chunk 3” thick. It is diamond finished (glossy) and has 16 cavities drilled for mass loading. This weighs over 25lbs. I estimate cost would be about $250 all told with filling etc. (see diagram).
I have loaded platters with one of three things; lead shot as in the Teres Platter, Tungsten Powder (which couples better to the acrylic and gives more damping. Thirdly I have a home brew of rubber/lead/Epoxy that I think simulates the RDC material in the Clearlight products.
Each makes the Acrylic sound different.
I have made other platters, Acrylic is fast, PVC is nice also (see Galibier Design platters) and their talk.
I have not done as much experimenting with PVC but I have mass loaded with lead shot.
I usually buy bearings rather than have special made, that way you can get replacements. Either the Teres ($295 standard shaft on ball), Michell (Gyrodec, $249 inverted ball) or I have just ordered some VPI (HW19 NOS for $100 standard shaft and ball) I’ll see how they sound.
I was also asked to make a heavy platter for a Rega bearing. I made the platter about 5” deep at the edge, 15mm across the hub, used a ruby ball/Teflon thrust pad/aluminum hub (Deepgroove). Using a deep platter I though would reduce the side load on the platter bearing. I did have the brass part of the bearing made for it, because I wanted more mass than the standard Rega item, but I did not add any bushes. The standard Rega part is $45 so getting one made was the same order of cost.
My latest platter adventure is going to be a stabilized wood product, I’ve been asked for one by a friend. I’m interested to see how this compares to the Acrylic and the Teres wood platter that I can get a listen too on occasion.
Hope that’s of interest.
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