One idea you could try is a 1/2 " machined acrylic mat. The question of tracking weight is not the only one. EMF in the coils also. The mat if designed carefully could be for anyone as a good upgrade, the platter rings.
I learnt recently a very usnusual thing. Often the resonces of platters, square plates etc follows the 1.618 ratio ( root 5 plus 1 all divided by 2 ). Big Ben is 95 Hz + 154 Hz and a metal plate of about 15 x 15 inches 264 Hz and 427Hz. Higher up I suspect the material itself dicates the frequencies. This slightly surprised me as I thought it might be exact multiples. The timbre so to speak. We don't want timbre when a turntable nor do we want over damping as it is the negative of resonance.
On the subject of alternate platters and upper platters..
I recall looking at show report photos from RMAF 2018 and saw this shot of an ultra thick platter sitting atop a TD124. No story to go with. Just the photo. And that got me thinking. Well, obviously someone else was thinking about it or that photo would not exist. But what if the folks at Lenco Hell made one of their spindle extensions and extra thick platters for the TD124?
Obviously the clutch doesn't have enough strength to lift much more than the oem upper platter but...do we really need the clutch? Or do I suggest something heretical!
Here are some shots taken from Lenco Hell:
Apparently the metal piece, the spindle extension seen in the second photo slips over the existing spindle pin of the existing Lenco and then fits neatly into the spot-faced underside of one of their Corian upper platters. Obviously this adds mass to the platter system, but we can also see that it elevates the record above the oem platter underneath. And, in the case of the Thorens, the iron platter is now further apart (below) from the magnetic fields of the moving coil cartridge above busily working in the record groove.
Again, you lose clutch function...and this really does intrude into the way one handles a TD124----but.
Above shot: sn 13943, my TD124 with upper aluminum platter removed and in its place is this Boston Audio Mat2 machined graphite mat. What if one took the idea of the Lenco Hell platter extension but executed it in graphite? But much thicker...say 1 inch thickness of machined graphite!
Above: peering into the void -- rubber pucks on the oem iron platter now supporting the BA Mat2.
The key to all this is how well does the TD124 function without its clutch. To start and stop the drive train with every side of the record? Well mine seems to work just fine that way. It gets up to speed within a revolution and when fully warmed up the strobe reports that speed stability remains stationary.
So the key to operating a TD124 without its clutch is to have a healthy motor and drive train. Which by now we should all have.
-Steve
I recall looking at show report photos from RMAF 2018 and saw this shot of an ultra thick platter sitting atop a TD124. No story to go with. Just the photo. And that got me thinking. Well, obviously someone else was thinking about it or that photo would not exist. But what if the folks at Lenco Hell made one of their spindle extensions and extra thick platters for the TD124?
Obviously the clutch doesn't have enough strength to lift much more than the oem upper platter but...do we really need the clutch? Or do I suggest something heretical!
Here are some shots taken from Lenco Hell:
Apparently the metal piece, the spindle extension seen in the second photo slips over the existing spindle pin of the existing Lenco and then fits neatly into the spot-faced underside of one of their Corian upper platters. Obviously this adds mass to the platter system, but we can also see that it elevates the record above the oem platter underneath. And, in the case of the Thorens, the iron platter is now further apart (below) from the magnetic fields of the moving coil cartridge above busily working in the record groove.
Again, you lose clutch function...and this really does intrude into the way one handles a TD124----but.
Above shot: sn 13943, my TD124 with upper aluminum platter removed and in its place is this Boston Audio Mat2 machined graphite mat. What if one took the idea of the Lenco Hell platter extension but executed it in graphite? But much thicker...say 1 inch thickness of machined graphite!
Above: peering into the void -- rubber pucks on the oem iron platter now supporting the BA Mat2.
The key to all this is how well does the TD124 function without its clutch. To start and stop the drive train with every side of the record? Well mine seems to work just fine that way. It gets up to speed within a revolution and when fully warmed up the strobe reports that speed stability remains stationary.
So the key to operating a TD124 without its clutch is to have a healthy motor and drive train. Which by now we should all have.
-Steve
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Hi Steve,
The clutch really helps the motor survive the spin-up process with the heavy platters. Once you get close to the speed of the motor, the clutch locks up and is out of the picture. The question now becomes, do you have a clutch that needs to be fixed instead of being defeated?
-Chris
The clutch really helps the motor survive the spin-up process with the heavy platters. Once you get close to the speed of the motor, the clutch locks up and is out of the picture. The question now becomes, do you have a clutch that needs to be fixed instead of being defeated?
-Chris
I myself lamost never use the clutch, but just let the platter go through while changing the records.
Actually, I do use my clutch when I have the oem aluminum platter on. It is convenient and habit forming in an enjoyable way. However there are limits to just how much load that thin piece of stamped sheet steel --that we call the clutch lever -- can carry.
In that regard I think anatech's question is useful. If you prefer not to use the clutch, is it operating correctly?
When we continue to add mass to the "upper platter" we ultimately reach a load that the clutch lever can't carry. That is what the clutch talk is concerned with.
The intent of my post, which has been distracted from, is not about whether or not we like the clutch, or if we even know how to adjust it, --or as is offen the case, to straighten a bent upper platter -- it is about a convenient means of adding mass and height to the platter system that would be less expensive than buying a non-magnetic platter from Swissonor. Or a stainless steel platter from Mirko---if he's still in business. *
So with regard to Nigel Pearson's post #2662 on July 19th, I note that if someone with a machine shop and the appropriate skills could reproduce essentially what Lenco Hell is doing with Lencos -- but for the TD124 -- it might be interesting. Only let's make the upper platters thicker and use materials other than just Corian. Graphite, for instance.
-Steve
*(I haven't heard from Mirko in a couple of years and he does not answer emails.)
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Are you calling the upper platter lift-off device a clutch?
I have repaired a number of TD-124 turntables over the years and keep forgetting they do not have a clutch, whereas the rest of the newer models do. My error with that mental slip. With the tight belt and idler wheel, the motor is tightly coupled to the sub-platter. Any attempt at using a clutch would have resulted in a large, beefy affair.
I do remember that at the time when the TD-124 was being marketed, most manufacturers were advertising how quickly their tables would reach playing speed - something a radio station or maybe an early DJ would benefit from. I can't remember which turntable it was, but one of them would reach 33 1/3 RPM in 1/3 of a revolution.
It took a few years before the more familiar figures for stability and rumble figures became normal, and those specs are more useful to a domestic use table might be.
As for the upper platter, what would adding mass to that be good for? Once it makes contact with the rubber pads, It "connects" to the lower platter and takes on its mass as far as the record is concerned. If you want to improve that coupling, I can see where a different connection than the rubber bumpers (for want of a better description) would work. A thin Sorbothane product might make a huge difference without adding any weight to the top platter. Just make it the same thickness as the original bumpers and you wouldn't need to change anything in the setup. Using more of them would distribute the connection and maybe even damp the upper platter more.
-Chris
I have repaired a number of TD-124 turntables over the years and keep forgetting they do not have a clutch, whereas the rest of the newer models do. My error with that mental slip. With the tight belt and idler wheel, the motor is tightly coupled to the sub-platter. Any attempt at using a clutch would have resulted in a large, beefy affair.
I do remember that at the time when the TD-124 was being marketed, most manufacturers were advertising how quickly their tables would reach playing speed - something a radio station or maybe an early DJ would benefit from. I can't remember which turntable it was, but one of them would reach 33 1/3 RPM in 1/3 of a revolution.
It took a few years before the more familiar figures for stability and rumble figures became normal, and those specs are more useful to a domestic use table might be.
As for the upper platter, what would adding mass to that be good for? Once it makes contact with the rubber pads, It "connects" to the lower platter and takes on its mass as far as the record is concerned. If you want to improve that coupling, I can see where a different connection than the rubber bumpers (for want of a better description) would work. A thin Sorbothane product might make a huge difference without adding any weight to the top platter. Just make it the same thickness as the original bumpers and you wouldn't need to change anything in the setup. Using more of them would distribute the connection and maybe even damp the upper platter more.
-Chris
Hi Chris, I think there is confusion in that some of us call the device that disengages the upper and lower platters, a clutch.
My concern is with the cast iron lower platter impacting the VTF of cartridges with strong magnets, as the Ortofon SPU series are reputed to have.
Also, as Nigel pointed out there may be some EMF being induced as well.
My concern is with the cast iron lower platter impacting the VTF of cartridges with strong magnets, as the Ortofon SPU series are reputed to have.
Also, as Nigel pointed out there may be some EMF being induced as well.
The TD124 always had a clutch. It functions by lifting the upper platter up off the spinning flywheel below it and also by dropping the upper platter onto the spinning flywheel below. This function was intended to give the deck appeal to radio stations in that you had instant-on sound on que. Its sole purpose.
re: more massive upper platter and what it might be good for. One thing would be to move the phono cartridge further away from the iron platter below it, thus eliminating any electro magnetic interraction between the iron platter and the phono cartridge. Particularly moving coil cartridges, such as an SPU, which have much stronger magnets than do moving magnet and moving iron cartridges -- generally.
Another suggested benefit would be the added mass which would thus add additional force to the moment of inertia at the rim. Thus, a greater driving force.
Still another benefit would be the use of alternate materials which have lesser tendencies to ring -- and -- further isolation from any bearing and drive train noise that would otherwise find a way into the record groove. Intended result - quieter noise floor as well as lower distortion being generated at the point of pickup.
re: rubber pucks and coupling between upper and lower platter. The goal would be to -- de-couple -- the upper from the lower platters in so far as noise transfer between them is concerned. At one time I believe Jim Campbell in PA was selling a silicone puck as replacement for the original rubber pucks Thorens used on the TD124. I tried a set and thought that it worked to good effect, although the silicone pucks did not handle the wear and tear of the action and began to break up around the edges. Though they continued to function just fine, and perhaps they dropped the noise floor just barely enough to be percieved as an improvement in clarity when listening for the difference very closely.
-Steve
Just a thought then.
It would seem to me that some extra distance between the lower and upper platters would be a benefit - yes?
There is a make of platter mats that is slightly tacky on one side that comes in various thicknesses. I intend to buy a couple for my newer Thorens tables where I used to use a Platter Matter. These would serve the dual purpose of spacing the platters apart for the thick ones, and decoupling the platters acoustically while also damping the top platter. An older Platter Matter could be used as an experiment, but they become hard on the top surfaces. So they will at least let you know if the thickness would be effective.
Another thought would be to have a circular steel plate stamped out and sandwich it between two platter mats. This would shield the cartridge from the lower platter. Degauss that part first and maybe also the lower platter.
-Chris
It would seem to me that some extra distance between the lower and upper platters would be a benefit - yes?
There is a make of platter mats that is slightly tacky on one side that comes in various thicknesses. I intend to buy a couple for my newer Thorens tables where I used to use a Platter Matter. These would serve the dual purpose of spacing the platters apart for the thick ones, and decoupling the platters acoustically while also damping the top platter. An older Platter Matter could be used as an experiment, but they become hard on the top surfaces. So they will at least let you know if the thickness would be effective.
Another thought would be to have a circular steel plate stamped out and sandwich it between two platter mats. This would shield the cartridge from the lower platter. Degauss that part first and maybe also the lower platter.
-Chris
Maybe I’ll break down and order the Schopper non-magnetic platter. Although it’s C$2K
Is that what you are using Kevin?
No, I'm using a Mirko stainless steel platter on one, and an OEM cast iron platter on the other. I also no longer use cartridges that operate on magnetic principles so the issue is now moot for me - I'm using Panasonic strain gauge cartridges.
Well, that’s certainly one way to circumvent the potential problem!
Very cool, I’ve never had a chance to hear one of those.
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How to remove the tension washer like clip that holds main bearing thrust ball
Hi, TD 124fans:
I have a td 125 mk ii which I like. After I had read this forum (good read) I went ahead buying an used TD 124ii (#80582). I have had fun doing restoration. I have done motor rebuilding,tuning stepped pulley, replacing capacitor, light bulb and idler wheel. The table improved a lot. Now I am doingsecond stage of restoring: bush bearings. I am now having aproblem: I cannot remove the tension washer clip that holds the 6mm thrust steel ball ofthe main bearing assembly. The washer clip and the steel ball looks factory original but the steel ball is worn. I tried using precision screwdriver and utility blade to insert into one of the four tiny cuts on the washer clip in order to snap it out. But the washer clip would not budge at all. In fact it seemed that both the precision screwdriver and utility blade could not get into the cut much. Any idea? Thanks a lot.
Michael
California
Hi, TD 124fans:
I have a td 125 mk ii which I like. After I had read this forum (good read) I went ahead buying an used TD 124ii (#80582). I have had fun doing restoration. I have done motor rebuilding,tuning stepped pulley, replacing capacitor, light bulb and idler wheel. The table improved a lot. Now I am doingsecond stage of restoring: bush bearings. I am now having aproblem: I cannot remove the tension washer clip that holds the 6mm thrust steel ball ofthe main bearing assembly. The washer clip and the steel ball looks factory original but the steel ball is worn. I tried using precision screwdriver and utility blade to insert into one of the four tiny cuts on the washer clip in order to snap it out. But the washer clip would not budge at all. In fact it seemed that both the precision screwdriver and utility blade could not get into the cut much. Any idea? Thanks a lot.
Michael
California
Volken,
Thanks for the advice. I did use a similar screwdriver but didn't get the tension clip off. It seems that you insert the screwdriver into the tiny gap between the steel ball and the tension clip and pry the tension clip upward. Is my observation correct? I tried to insert the screwdriver into one of the four tiny line cuts on the clip and that may be why I couldn't do it.
Thanks again.
Michael