Another source of belts would be Joel Boltreux. Former Thorens employee who frequents the Vinyl Engine and offers support within the Thorens forum there. He sells various maintenance parts and supplies for Thorens players. I'm sure he has a TD124 belt. If you haven't already made contact with Joel, he is responsive to emails. He goes by the moniker 'Violette' I think I will ask Joel about the Thakker belt and if the one he sells is the same belt or if it is a different one.
Another source for Thorens belts is Rolf Kelch. Rolf is sometimes difficult to get in touch with. However he understands the vintage Thorens players and can source the original belt from the same belt factory in Lahr that produced belts for Thorens back in the day. Link to Rolf:
Rolf Kelch
I have purchased three TD124 belts from Elexatelier. Link to Elex:
Thorens Turntable Belts Record Player Audio Equipment Electronic Parts: Elex Atelier
These seem like a close fit providing you don't use them over the larger 50hz pulley. Making note that I recommend Elex only for the TD124 belt and not the later belt drive models like the TD160, etc.
At least there are some more alternatives for you to try.
-Steve
-Steve
Hi Steve,
I asked Joel about TD-124 belts some weeks ago, (I'm active at VE, tapeheads, and AA as well as here) he informed me that unfortunately he has completely sold out. He is also of the impression that there was a belt specifically for models sold configured for 60Hz, and another for 50Hz. I have not been able to find anything proving that is true, but Thorens does state in the last service manual that there is just one belt for 50 or 60Hz operation and all belts I have seen so far are about 12.1" when new, and stretch to about 12.8" or so when used but still ok. (Some belts are listed as actually being 320mm, but I've yet to see a one new out of the bag that was much over 300mm, probably a difference in the way I measure them. [untensioned])
Thorens lists two belts the CB908 and the CB965 in the service manual, but I believe the CB908 is just an older part number that was superseded by the CB965. (It's not clear to anyone unfortunately)
My original belt is virtually identical in length to the Thakker sourced Thorens CB965 as is the new belt from turntablebasics.com. They are all different thicknesses with the original being much thinner and more pliant than the other two.
What I come away with so far is that while they may all be the same width and length, they differ significantly by thickness and durometer. I currently have 3 belts and will eventually get one or two more for evaluation. Fortunately for the most part they aren't too expensive.
I suspect the belts Technical and General are selling are the same Thorens sourced belts that Thakker sells, but am awaiting confirmation.
I will check out Elexatelier, and Rolf Ketch..
I asked Joel about TD-124 belts some weeks ago, (I'm active at VE, tapeheads, and AA as well as here) he informed me that unfortunately he has completely sold out. He is also of the impression that there was a belt specifically for models sold configured for 60Hz, and another for 50Hz. I have not been able to find anything proving that is true, but Thorens does state in the last service manual that there is just one belt for 50 or 60Hz operation and all belts I have seen so far are about 12.1" when new, and stretch to about 12.8" or so when used but still ok. (Some belts are listed as actually being 320mm, but I've yet to see a one new out of the bag that was much over 300mm, probably a difference in the way I measure them. [untensioned])
Thorens lists two belts the CB908 and the CB965 in the service manual, but I believe the CB908 is just an older part number that was superseded by the CB965. (It's not clear to anyone unfortunately)
My original belt is virtually identical in length to the Thakker sourced Thorens CB965 as is the new belt from turntablebasics.com. They are all different thicknesses with the original being much thinner and more pliant than the other two.
What I come away with so far is that while they may all be the same width and length, they differ significantly by thickness and durometer. I currently have 3 belts and will eventually get one or two more for evaluation. Fortunately for the most part they aren't too expensive.
I suspect the belts Technical and General are selling are the same Thorens sourced belts that Thakker sells, but am awaiting confirmation.
I will check out Elexatelier, and Rolf Ketch..
Last edited:
One Very Temperamental Turntable
Tonight the unthinkable or in the case of a TD-124 the not so unthinkable occurred: It just flat out refused to run without a push..
I pulled the table out of the system, removed the arm and pulled the platter. Applied power and listened to the motor just buzz. A tap got it going. When turning by hand it seemed a bit tighter than I remembered. I applied some additional lubricant (turbine oil this time) and attempted to improve the alignment of the bearings a bit. It definitely loosened up.. This I think does not speak well of the bearings I installed and if it continues to be a problem I will clean and reinstall the originals. Word to the wise, the new ones may not be as good as the originals.
I'm also wondering about the 3 in 1 20wt electric motor oil, athough I observe no issues with the oil in the main bearing well which of course is not getting warm.
The oil in the motor is now a mix of turbine oil and 20wt electric motor oil, we'll see how that stands up..
I'm very concerned about the motor issue as an mtbf of two weeks is not very long..
This may explain why most E50 motor rebuilders run the motor for a week and disassemble, clean and relubricate after servicing them.
I unfortunately also discovered that overfilling the main bearing well is not as benign as some would have you believe, the oil eventually gets everywhere. I carefully cleaned up the mess, put everything back together to a cacophony of bad noises, and really poor performance - pulled it all apart and tried again - now it is about as quiet as before and starts quickly.
I will comment in a separate post about some of the other things I discovered relating to belt noise issues tonight as they ought to stand alone. See next post.
Tonight the unthinkable or in the case of a TD-124 the not so unthinkable occurred: It just flat out refused to run without a push..
I pulled the table out of the system, removed the arm and pulled the platter. Applied power and listened to the motor just buzz. A tap got it going. When turning by hand it seemed a bit tighter than I remembered. I applied some additional lubricant (turbine oil this time) and attempted to improve the alignment of the bearings a bit. It definitely loosened up.. This I think does not speak well of the bearings I installed and if it continues to be a problem I will clean and reinstall the originals. Word to the wise, the new ones may not be as good as the originals.
I'm also wondering about the 3 in 1 20wt electric motor oil, athough I observe no issues with the oil in the main bearing well which of course is not getting warm.
The oil in the motor is now a mix of turbine oil and 20wt electric motor oil, we'll see how that stands up..
I'm very concerned about the motor issue as an mtbf of two weeks is not very long..
This may explain why most E50 motor rebuilders run the motor for a week and disassemble, clean and relubricate after servicing them.
I unfortunately also discovered that overfilling the main bearing well is not as benign as some would have you believe, the oil eventually gets everywhere. I carefully cleaned up the mess, put everything back together to a cacophony of bad noises, and really poor performance - pulled it all apart and tried again - now it is about as quiet as before and starts quickly.
I will comment in a separate post about some of the other things I discovered relating to belt noise issues tonight as they ought to stand alone. See next post.
Last edited:
Belt And Intermediate Pulley Noise
I made an interesting discovery as a result of my TD-124 refusing to run.
Basically I discovered that small changes in motor pulley height have a very big effect on the overall belt and intermediate pulley noise level. The table must be absolutely level when you do this adjustment, and the idler pulley should be removed in order to make it easier to perform.
Basically what you want to do is adjust the pulley height for minimum noise and you need to do this when the motor bushings are replaced and it probably would not hurt to check it from time to time.
I briefly evaluated all three belts I currently have on hand, and the original belt was still the quietest, the Thakker was significantly noisier, but the difference appeared not to be as great as previously was the case, and the noisiest belt of all was the one from Turntablebasics which might improve with some run in time.. This belt also seemed to fit more tightly than the other two and was not as elastic.. In operation the belt continued to exhibit the odd ripply appearance I noted when I got it. I would call this the belt of last resort..
I made an interesting discovery as a result of my TD-124 refusing to run.
Basically I discovered that small changes in motor pulley height have a very big effect on the overall belt and intermediate pulley noise level. The table must be absolutely level when you do this adjustment, and the idler pulley should be removed in order to make it easier to perform.
Basically what you want to do is adjust the pulley height for minimum noise and you need to do this when the motor bushings are replaced and it probably would not hurt to check it from time to time.
I briefly evaluated all three belts I currently have on hand, and the original belt was still the quietest, the Thakker was significantly noisier, but the difference appeared not to be as great as previously was the case, and the noisiest belt of all was the one from Turntablebasics which might improve with some run in time.. This belt also seemed to fit more tightly than the other two and was not as elastic.. In operation the belt continued to exhibit the odd ripply appearance I noted when I got it. I would call this the belt of last resort..
CB965 Replacement Belt, Clutch Adjustment, Idler Pulley
Spent a little more time after dinner investigating the scraping noises when the clutch was engaged - it turns out that there is a very tiny difference in platter height with the original bearing cap and thrust plate and the new one which apparently is significantly lower.. The rear clutch finger apparently was adjusted just a little higher than the others and since the zamac platter is not precisely machined there was a low spot which was hitting on just this one finger. (run out is probably no more than 10 thou or so..) A very minor adjustment took care of that. Silent now.
I decided after coming back downstairs and hearing a fair amount of noise as I approached the turntable that I would try the CB965 belt I purchased from Thakker. I installed it and made some minor tweaks to the motor pulley height and I was able to get it reasonably quiet, on this front I am basically giving up as it's clearly hopeless - you'd have to be deaf not to hear the noise, but I have decided not to obsess over this any longer. The current Thorens CB965 belt is acceptable - in the long term if not I will just go back to the SME table I was using previously or get something else. Make no mistake this is an oddly noisy table, but the noise does not seem to get coupled to a significant degree into the platter as long as the idler is ok. Probably just not enough energy there to excite the platter given the huge differences in mass..
With all of the tinkering lately the idler pulley had gotten quite slick, so I treated it another wash in hot soapy water and a single pass with the scotch brite. This has returned the table to the very quick acceleration I remember when I first got it running.
The motor seems to be running fine and the bearing drag is greatly reduced.
This was observed after the motor had been off for about 45 minutes, so hopefully this will reflect to a completely cold motor as well.
Spent a little more time after dinner investigating the scraping noises when the clutch was engaged - it turns out that there is a very tiny difference in platter height with the original bearing cap and thrust plate and the new one which apparently is significantly lower.. The rear clutch finger apparently was adjusted just a little higher than the others and since the zamac platter is not precisely machined there was a low spot which was hitting on just this one finger. (run out is probably no more than 10 thou or so..) A very minor adjustment took care of that. Silent now.
I decided after coming back downstairs and hearing a fair amount of noise as I approached the turntable that I would try the CB965 belt I purchased from Thakker. I installed it and made some minor tweaks to the motor pulley height and I was able to get it reasonably quiet, on this front I am basically giving up as it's clearly hopeless - you'd have to be deaf not to hear the noise, but I have decided not to obsess over this any longer. The current Thorens CB965 belt is acceptable - in the long term if not I will just go back to the SME table I was using previously or get something else. Make no mistake this is an oddly noisy table, but the noise does not seem to get coupled to a significant degree into the platter as long as the idler is ok. Probably just not enough energy there to excite the platter given the huge differences in mass..
With all of the tinkering lately the idler pulley had gotten quite slick, so I treated it another wash in hot soapy water and a single pass with the scotch brite. This has returned the table to the very quick acceleration I remember when I first got it running.
The motor seems to be running fine and the bearing drag is greatly reduced.
This was observed after the motor had been off for about 45 minutes, so hopefully this will reflect to a completely cold motor as well.
Further Comments
This hasn't been a great day in the Thorens saga, but I suppose if you have several of them if one malfunctions at any given time you can just use another..
I'm fairly irritated at the moment, the saving grace is this thing is like a Ferrari, when it's right it's very right.. It just needs a little more help than I am used to - in fairness this table sat unused for 39yrs and to some extent resurrecting the dead might be expected to result in some issues of the sort I have been dealing with..
In retrospect of course I can see something was going on.. The fact that over the past few days it was getting more and more recalcitrant to run, and the fact that I could no longer adjust it to run on speed when cold might have been a hint. Increasing drag in the motor bearings was eating up precious torque, it still ran close enough to on speed when cold not to be noticeable until today, but today it was so bad I had to face the inevitable...
I thought I put enough oil in the new bearing assemblies, and these are aftermarket oilite bronze bearings so they are supposedly self lubricating. I'm going to have to keep an eye on these because they aren't behaving as expected. I added a significant amount of oil tonight and the motor is running as it did a couple of weeks back, hopefully I will not have to do this again quite so soon. Should I have to I may need to face the reality that I have to bake the old bearings, oil them, and reinstall them as it would then be apparent that the new ones aren't so good. In my zeal to address known and in this case obvious motor problems I may have created one, and I probably need to take this thing apart again and clean everything..
Right at this moment it is back to sounding great, creating a beguiling listening experience - its great strength.. Anxiety lurks in the background..
More coming of course..
This hasn't been a great day in the Thorens saga, but I suppose if you have several of them if one malfunctions at any given time you can just use another..
I'm fairly irritated at the moment, the saving grace is this thing is like a Ferrari, when it's right it's very right.. It just needs a little more help than I am used to - in fairness this table sat unused for 39yrs and to some extent resurrecting the dead might be expected to result in some issues of the sort I have been dealing with..
In retrospect of course I can see something was going on.. The fact that over the past few days it was getting more and more recalcitrant to run, and the fact that I could no longer adjust it to run on speed when cold might have been a hint. Increasing drag in the motor bearings was eating up precious torque, it still ran close enough to on speed when cold not to be noticeable until today, but today it was so bad I had to face the inevitable...
I thought I put enough oil in the new bearing assemblies, and these are aftermarket oilite bronze bearings so they are supposedly self lubricating. I'm going to have to keep an eye on these because they aren't behaving as expected. I added a significant amount of oil tonight and the motor is running as it did a couple of weeks back, hopefully I will not have to do this again quite so soon. Should I have to I may need to face the reality that I have to bake the old bearings, oil them, and reinstall them as it would then be apparent that the new ones aren't so good. In my zeal to address known and in this case obvious motor problems I may have created one, and I probably need to take this thing apart again and clean everything..
Right at this moment it is back to sounding great, creating a beguiling listening experience - its great strength.. Anxiety lurks in the background..
More coming of course..
Last edited:
That's a major problem that indicates something very fundamental is not right. One can only guess, since you are the only witness. However it sounds as if the motor was seizing up due to excessive friction at the motor shaft to bearing interface.
I would not be too quick to point the finger of blame toward the new bearings. Prior to assembly one can simply fit a bearing over the motor shaft and observe the snugness of fit between bearing and shaft. Ideally there should be .0007 - .0010 inches of clearance between bearing walls and shaft.
The worn bearings will likely exhibit a greater clearance than this. Not everyone is equipped to measure inside and outside diameters with mics and bore gages, in order to determine actual running clearances, but you can test fit the parts and observe any obvious excess slack or if the bearing seems rather tight and turns too stiffly.
Chances are high that your 20 wt electric motor lube and the so called 'turbine' oil (20 wt) are of very similar if not exactly the same formula. Either should work satisfactorily. Although I would certainly make sure that upon assembly both shaft, bearing and lube retaining felts are well saturated with the oil. Remembering that the Oilite bronze bushing material is of a highly porous and oil retaining type. The bushings need to be well soaked in oil prior to assembly.
Another consideration is that the bearing retainers and machine screw fasteners do not vibrate loose.
I use a small dab of loctite thread sealer on the threads of each screw as a final touch to ensure a permanent joint.
I wonder if the shaft to bearing alignment hadn't shifted?
Presumably, the voltage commutator had been set for North American current. (100 - 120 vac)
Above photo shows a mk1 set for NA current. Just noting this for anyone reading through the archives.
I think I would forgo any serious comparisons between drive belts until it is established that the motor is operating correctly and has been for a few weeks.
Belts will tend to stretch and become a better fit over time.
Setting drive pulley height should be straight-forward. Although it does make good sense to evaluate motor vibes versus drive pulley height by using a stethoscope to listen to the outer motor case, and chassis for each adjustment.
Lets not forget the motor mount grommets. If these are too soft, they won't hold the motor firmly enough to drive the step pulley/idler/platter without the motor twisting in its mounting. Such a situation might tend to lead one down false paths of analysis.
In other words....it should not be this hard.
re: main bearing lube.
The platter bearing. The mkII will be equipped with Oilite bronze bushings in the bearing housing. These are of the oil retaining type and do not require that the housing be filled with oil. However it doesn't hurt if there is a small volume of oil within the housing either, except when the housing is over-filled and upon assembly of the shaft, oil is displaced upward and into the interior space of the cast chassis. That's messy. Especially if oil is allowed to get on the drive belt or idler wheel...which will effect performance as well.
The other negative for having a volume of oil in the housing is that with the standard gasket and cover plate, the air pressure exerted upon assembly is enough to rupture the gasket and cause an immediate leak.
Prior to assembling the platter bearing shaft into the housing, I just apply some oil to the shaft and call that good enough. Perhaps a small amount is allowed to exist down in the thrust. More 20 wt.
-Steve
Hi Steve,
Thanks for the additional input. As long as the motor windings are intact I am not too concerned, as much of a nuisance as this is I can address the issue pretty quickly.
Yes my take on the bearings is that they were starting to seize, and the only likely explanation I have is that I did not add sufficient lubricant to the felts when I installed them. I have remedied that situation and will monitor and add a bit more if necessary.. It strikes me if I used insufficient lube the felts might actually wick oil out of the bearings.
All of the hardware is tight, I double checked. Bearing alignment is good.
I no longer have a mic so I can't measure the bearing clearances but there is no wear visibly evident on the shaft or original bearings.
The two lubricants I typically use appear to be different, the turbine oil is clear and has a viscosity I estimate at around 15wt sae, the other is the 20wt electric motor oil I have mentioned in previous posts, which is slightly golden in color.
The motor runs extremely quietly.. Time will tell as to what else I need to do to it.
The argument for filling the bearing well to a certain level is that the spindle then rides on an oil film at all bearing contact areas, but it is messy. I don't have the stock bearing cap and gasket at this point, and usually leave the spindle installed and remove the platter instead. I should note that the turntable as received had quite a lot of oil in the bearing well, (roughly comparable to what I now have in it) and this would have been as received since the table was never serviced prior to my receiving it.
The Thorens CB965 belt seems to be OK, based on the unverified conjecture that all is currently well. Only time will tell, and it only has a couple of hours of use so far. Pulley alignment definitely does play a major role. I think your comments on the bushings bear consideration and I guess I will order a set from Schopper sometime in the new year to try. The current bushings are definitely stiffer than the deteriorated originals.
Voltage range is 100-120V, and my line voltage is typically 118V..
Thanks for the additional input. As long as the motor windings are intact I am not too concerned, as much of a nuisance as this is I can address the issue pretty quickly.
Yes my take on the bearings is that they were starting to seize, and the only likely explanation I have is that I did not add sufficient lubricant to the felts when I installed them. I have remedied that situation and will monitor and add a bit more if necessary.. It strikes me if I used insufficient lube the felts might actually wick oil out of the bearings.
All of the hardware is tight, I double checked. Bearing alignment is good.
I no longer have a mic so I can't measure the bearing clearances but there is no wear visibly evident on the shaft or original bearings.
The two lubricants I typically use appear to be different, the turbine oil is clear and has a viscosity I estimate at around 15wt sae, the other is the 20wt electric motor oil I have mentioned in previous posts, which is slightly golden in color.
The motor runs extremely quietly.. Time will tell as to what else I need to do to it.
The argument for filling the bearing well to a certain level is that the spindle then rides on an oil film at all bearing contact areas, but it is messy. I don't have the stock bearing cap and gasket at this point, and usually leave the spindle installed and remove the platter instead. I should note that the turntable as received had quite a lot of oil in the bearing well, (roughly comparable to what I now have in it) and this would have been as received since the table was never serviced prior to my receiving it.
The Thorens CB965 belt seems to be OK, based on the unverified conjecture that all is currently well. Only time will tell, and it only has a couple of hours of use so far. Pulley alignment definitely does play a major role. I think your comments on the bushings bear consideration and I guess I will order a set from Schopper sometime in the new year to try. The current bushings are definitely stiffer than the deteriorated originals.
Voltage range is 100-120V, and my line voltage is typically 118V..
A quick Update
It's been almost two days since I relubed the motor and made some minor bearing adjustments. So far after a running time of 20 hrs or so everything seems fine. It came up to speed very quickly this morning, and was exactly on speed within 10 minutes and has not drifted at all in 4 hours.
I will keep an eye on this issue and perhaps add some additional lube to the motor bearings in a week or so. I think I may have failed to sufficiently wet the new felts with lubricant, however this bears monitoring as it is not clear to me how new bearings with sufficient lube in them should have ran nearly dry in a couple of weeks unless the felts actually can wick lubricant out of them.
I removed the Thakker sourced belt this morning, it offends me that I can hear so much mechanical racket from a couple of feet away - the old belt is much quieter, however I do need to investigate whether the new bushings are in some way responsible for this, but observed no real deflection of the motor mounts when I install or remove any of the belts I have on hand, but that doesn't mean it isn't happening. There is no audible difference in performance of the table when playing records between the old and new belts so this belt is definitely usable.
Just idle speculation on my part, as I learn more I will post what I figure out.
I'm rather happy with the performance otherwise, and I am sure i will eventually get all issues sorted out satisfactorily.
It's been almost two days since I relubed the motor and made some minor bearing adjustments. So far after a running time of 20 hrs or so everything seems fine. It came up to speed very quickly this morning, and was exactly on speed within 10 minutes and has not drifted at all in 4 hours.
I will keep an eye on this issue and perhaps add some additional lube to the motor bearings in a week or so. I think I may have failed to sufficiently wet the new felts with lubricant, however this bears monitoring as it is not clear to me how new bearings with sufficient lube in them should have ran nearly dry in a couple of weeks unless the felts actually can wick lubricant out of them.
I removed the Thakker sourced belt this morning, it offends me that I can hear so much mechanical racket from a couple of feet away - the old belt is much quieter, however I do need to investigate whether the new bushings are in some way responsible for this, but observed no real deflection of the motor mounts when I install or remove any of the belts I have on hand, but that doesn't mean it isn't happening. There is no audible difference in performance of the table when playing records between the old and new belts so this belt is definitely usable.
Just idle speculation on my part, as I learn more I will post what I figure out.
I'm rather happy with the performance otherwise, and I am sure i will eventually get all issues sorted out satisfactorily.
Last edited:
Thorens 124 Neon Bulb (Off Topic)
Sorry for being off topic, but if you need a bulb replacement try this:
RCA 991 Light Bulb, NOS For Thorens Turntables - eBay (item 390212816218 end time Dec-20-10 09:07:20 PST)
I just got one and it works just fine. Don't forget to try BO price.
David
Sorry for being off topic, but if you need a bulb replacement try this:
RCA 991 Light Bulb, NOS For Thorens Turntables - eBay (item 390212816218 end time Dec-20-10 09:07:20 PST)
I just got one and it works just fine. Don't forget to try BO price.
David
When motor is really right it will 'lock in' sooner. Although it may take some running in to see this, since it seems that no ones attempts at bearing alignments are as optimal as we would like. When you see the strobe operating within 1 % at a 1/2 dozen rpms on a cold start, and you get a solid lock within a minute or two, then the motor is working well.
That your drive train exhibits no speed drift is a good sign.
The felts should have been soaked in lube prior to assembly. I can think of at least two websites that offer a pictorial on motor assembly. Both of these sites will indicate fully saturated felts. Also, the bushings themselves need to be soaked for a day or more prior to assembly. This need comes about because very few have access to the correct vacuum ovens that are used to impregnate the Oilite bronze properly. Therefore soak in clean lube prior to assembly.
I have doubts that the felts could 'wick' lube out of the bushings. Rather, the bushings must have been dry or nearly dry when assembled. This would have been evident upon dis-assembly after the seizing episodes. If the bushings and shaft were found to be dry at that point, then it is highly likely that they were that dry upon the initial assembly.
The drive train of the TD124 should be silent when standing near it. Only if you put your ear directly over the the TT, within a few inches, should you hear only the faintest whisper/rustle of idler tire noise. All other members of the drive train should be silent. Rather than blaming the belt, we should examine that the step pulley bushings and shaft have been cleaned and lubed in the same oil as used in the motor. Then there is the idler wheel which also needs maintenance at its axle and bushings. Also, test the idler bushings for excess slop by attempting to tip the idler wheel at it its rim. It should be tight yet spin freely with no rattle. The tire surface itself is of concern. Listen for any audible 'knocking' while the TD124 is in operation. If knocking is evident, suspect a flat spotted idler tire.
Just to reaffirm.......I'm not so sure I would place the blame of a noisy drive train upon a new belt that carries the Thorens logo until all other possibilities have been eliminated as noted above.
Further comments:
If you feel the TT sounds good to your ears presently, and you are noticing the noisy drive train, wait until you get this TD124 fully sorted out. It really is an outstanding record player.
Down the road, try experimenting with different tonearms. The SME 3009 S2 are definitely good quality but there are others to play with.
-Steve
Hi Steve,
When I rebuilt the table I checked the condition of all of the components in the drive train. There is a concern with the idler pulley in that I can see a very small ripple in it, however it doesn't generate any noise or knocking, and it is perfectly round. There is no discernible play in the idler or intermediate pulley bearings. The noise has decreased substantially as the table has run today, it is no longer audible more than about six inches from the table with the original belt. Note also that the noise is present whether or not the idler is engaged (with the platter off) - it doesn't seem to add appreciably to the noise level.
I think the Thakker is acceptable from a performance perspective and the fact that is it somewhat less elastic could be pulling the motor out of alignment. A friend who just bought the same bushings commented that he was surprised at how soft they are. I gave him a loaner belt tonight and he will let me know if he hears anything like I am hearing here. His comment was that his table makes about the same level of noise as mine.
I am sure based on your comments that I made a serious mistake in not really drenching the felts in oil. The motor bearings were supposedly fully oil impregnated and ready to go when I purchased them, and were packed in oil. I did apply additional oil after assembly, and again on Sunday when I reported I was having an issue. I think I will "top off" again in a couple of days if I note any increase in drag. This morning it felt the same as it did after several hours of running the other day, but hard to judge.
I think even at start up the speed is well within 1% and had understood it took about 10 minutes to lock in, but have not timed it, definitely more than 5 minutes though. I would expect that the motor is not fully broken in at this point based on what you are saying.
I have a 3012 which will be the first arm I experiment with, eventually as my machining skills get better I'd like to clone a 12" Sheu arm, a project for the distant future I think.
Overall I am very pleased with the turntable, I take these issues to be part of the learning curve, and I also bear in mind that this turntable has not run in 4 decades so some minor issues are to be expected.
I guess the one thing I am wondering about is how much better off I would have been using all Swiss sourced parts in my rehab.. It was just easier to point and click on eBay, the press on these guys is all favorable, and I hadn't run into you yet - I'd have sourced some things differently in retrospect.
I've had the opportunity to listen to several homebrew and aftermarket mats and am definitely sticking with original mat - this is the first time I have ever preferred an OEM mat, but changing it messes in subtle ways with the qualities of this table that attracted me to it in the first place.
Honestly I can't imagine I really need anything else going forward, other than to satisfy curiosity, (which I have) and there are certainly decent upgrades like the Schopper platter, better plinths, arms and cartridges to take it further..
Last edited:
Another Update..
Checked early this morning to determine how quickly the turntable starts from cold, again it was up to playing speed in about 1/3rd of a platter revolution which is good news..
For good measure I added some additional oil to the top and bottom motor bearings as I believe Steve is correct and I simply did not use enough oil on the felts. I have seen all of the motor rebuild sites, and referred to them as I rebuilt the motor - I guess I scrimped a bit on the oil because of the mess the stuff makes.. It's very important to use sufficient oil, and even with pre-oiled bearings I would now recommend following at least part of the recommendations listed here: ƒg�[ƒŒƒ“ƒX THORENS model TD 124
It still takes about 10 minutes for my table to warm to the point where it attains set speed, but it is very cool down here in my listening room, and it is also pretty clear from the issues I've had that the new bearings are not broken in yet.. (Note that it is immediately usable - mine is running around 1% slow initially.)
I am coming to understand why many motor rebuilders run these motors continuously for a week, and then tear down, clean and relubricate them before re-installation in the table. I was anxious to get the table going and only ran in the motor for a couple of hours before installing it - just long enough so that it was no longer running excessively warm. I also haven't fully disassembled the motor and cleaned the bearings and shaft as I probably should - my reasoning was that the factory making these motors certainly didn't do this so why should I? Well once I achieve a couple of hundred hours of run time I now think I will pull it apart and clean it.
Checked early this morning to determine how quickly the turntable starts from cold, again it was up to playing speed in about 1/3rd of a platter revolution which is good news..
For good measure I added some additional oil to the top and bottom motor bearings as I believe Steve is correct and I simply did not use enough oil on the felts. I have seen all of the motor rebuild sites, and referred to them as I rebuilt the motor - I guess I scrimped a bit on the oil because of the mess the stuff makes..
It's very important to use sufficient oil, and even with pre-oiled bearings I would now recommend following at least part of the recommendations listed here: ƒg�[ƒŒƒ“ƒX THORENS model TD 124It still takes about 10 minutes for my table to warm to the point where it attains set speed, but it is very cool down here in my listening room, and it is also pretty clear from the issues I've had that the new bearings are not broken in yet.. (Note that it is immediately usable - mine is running around 1% slow initially.)
I am coming to understand why many motor rebuilders run these motors continuously for a week, and then tear down, clean and relubricate them before re-installation in the table. I was anxious to get the table going and only ran in the motor for a couple of hours before installing it - just long enough so that it was no longer running excessively warm. I also haven't fully disassembled the motor and cleaned the bearings and shaft as I probably should - my reasoning was that the factory making these motors certainly didn't do this so why should I? Well once I achieve a couple of hundred hours of run time I now think I will pull it apart and clean it.
Last edited:
It's still running in.. The good news is that I have a friend with a close serial # MKII which is behaving quite similarly even down to the noise issues with different belts, unfortunately like mine it also has the geltec bushings.
I guess have no idea where my belt came from because according to every reputable source I have contacted the belt has always been 0.9mm thick, but mine is definitely 0.58mm thick and runs a lot quieter with the geltec bushings installed than my new CB965 although as I have indicated there is no audible consequence to performance when playing records - the machine is just a bit noisier.
I should be able to listen to the drive train noise in an unrestored, but running low serial # MKI in the near future. The owner says it is very quiet. (It will be restored prior to actual use.)
Probably flogged this subject to death, but I took the table apart again today and looked at everything again in excruciating detail.
The motor now comes up to speed very quickly, and after an hour's operation is barely warm to the touch. It appears that the motor is now largely broken in.
I have examined the motor bushing issue and it appears to me that all three deflect equally and quite minimally and deflection is a function of the length and elasticity of the belt. There is no evidence that the motor pulley running surfaces aren't perfectly parallel to the intermediate pulley running surfaces.
I also played with pulley alignment and even went so far as to deliberately slightly mis-align (angle - the other more appropriate word is censured by the forum software) the motor by hand relative to the intermediate pulley, and discovered this has an almost indiscernible effect on the noise I have been complaining about. Changing the motor pulley height also has minimal effect as long as any part of the belt is still riding on the crown of the intermediate pulley. I like mine well centered, and there it stays.
The intermediate pulley bearing and shaft are free of any evidence of wear, and my dial indicator was not able to detect any significant eccentricity in the belt running surface or the pulley. (A couple of thousands or less - better than my dial indicator) This tells me there is nothing wrong with the pulley other than what it is made of - it is really resonant. This component was significantly redesigned between the MKI and the MKII to improve some other aspect of its performance, but I wonder if the bearing assembly as originally installed in the pulley provided some damping...
Belt elasticity, thickness and tension all seem to have a very large effect on the noise levels generated followed closely by surface imperfections on the motor and intermediate pulleys. I had previously checked the intermediate pulley for surface roughness and it appears reasonably if not perfectly smooth. The crown of the 60Hz pulley on the motor was another matter - I'm not sure what the issue was but I lightly burnished the surface and was able to significantly reduce excitation of the belt by surface roughness on the motor pulley - this had a small but noticeable effect on noise, however it also seems to have resulted in a significant reduction of friction. (This could even be old belt residue..) All of this points to the need to keep things scrupulously clean. I also noted that a wet belt (alcohol - I don't care about the longevity of this belt..) runs dead silent - so I am thinking that some talc might actually be in order here.
I have, umm.... ordered more belts to try.. I am currently running the Thakker Thorens CB965 and this is definitely the second quietest of the three belts I currently own. The third belt by turntablebasics is a good deal noisier. I want to see if the Thakker belt will quiet down with more running time and/or talc as I need a long term solution - the original belt serves as a reference.
I have decided barring some unforeseen disaster I am going to move on to plinth and other issues as it is clear I am wasting my time. Nothing is audible at the cartridge, the table is extremely quiet playing anything including the lead out grooves at the end of a side. The main bearing is excellent. I will soon get to hear the mechanical noise levels of an unrestored MKI (allegedly very quiet) and a restored MKII (the owner reports having exactly the same noise issues) and that will be more revealing I think. FWIW I am not expecting any surprises..
The areas I do think worth most immediately addressing are a better plinth and that zamac platter - I am pretty sure that its colorations are audible as a bit of extra zing in the upper midrange. I'm going to try (reversibly) damping the platter as some changes I have tried as noted previously have not really been an improvement - they might have addressed an issue, but the medicine was far worse than the disease..
Anyway for all of the commentary I'm pretty happy with what I am hearing, and there is potential to go a lot further as resources permit.
The motor now comes up to speed very quickly, and after an hour's operation is barely warm to the touch. It appears that the motor is now largely broken in.
I have examined the motor bushing issue and it appears to me that all three deflect equally and quite minimally and deflection is a function of the length and elasticity of the belt. There is no evidence that the motor pulley running surfaces aren't perfectly parallel to the intermediate pulley running surfaces.
I also played with pulley alignment and even went so far as to deliberately slightly mis-align (angle - the other more appropriate word is censured by the forum software) the motor by hand relative to the intermediate pulley, and discovered this has an almost indiscernible effect on the noise I have been complaining about. Changing the motor pulley height also has minimal effect as long as any part of the belt is still riding on the crown of the intermediate pulley. I like mine well centered, and there it stays.
The intermediate pulley bearing and shaft are free of any evidence of wear, and my dial indicator was not able to detect any significant eccentricity in the belt running surface or the pulley. (A couple of thousands or less - better than my dial indicator) This tells me there is nothing wrong with the pulley other than what it is made of - it is really resonant. This component was significantly redesigned between the MKI and the MKII to improve some other aspect of its performance, but I wonder if the bearing assembly as originally installed in the pulley provided some damping...
Belt elasticity, thickness and tension all seem to have a very large effect on the noise levels generated followed closely by surface imperfections on the motor and intermediate pulleys. I had previously checked the intermediate pulley for surface roughness and it appears reasonably if not perfectly smooth. The crown of the 60Hz pulley on the motor was another matter - I'm not sure what the issue was but I lightly burnished the surface and was able to significantly reduce excitation of the belt by surface roughness on the motor pulley - this had a small but noticeable effect on noise, however it also seems to have resulted in a significant reduction of friction. (This could even be old belt residue..) All of this points to the need to keep things scrupulously clean. I also noted that a wet belt (alcohol - I don't care about the longevity of this belt..) runs dead silent - so I am thinking that some talc might actually be in order here.
I have, umm.... ordered more belts to try.. I am currently running the Thakker Thorens CB965 and this is definitely the second quietest of the three belts I currently own. The third belt by turntablebasics is a good deal noisier. I want to see if the Thakker belt will quiet down with more running time and/or talc as I need a long term solution - the original belt serves as a reference.
I have decided barring some unforeseen disaster I am going to move on to plinth and other issues as it is clear I am wasting my time. Nothing is audible at the cartridge, the table is extremely quiet playing anything including the lead out grooves at the end of a side. The main bearing is excellent. I will soon get to hear the mechanical noise levels of an unrestored MKI (allegedly very quiet) and a restored MKII (the owner reports having exactly the same noise issues) and that will be more revealing I think. FWIW I am not expecting any surprises..
The areas I do think worth most immediately addressing are a better plinth and that zamac platter - I am pretty sure that its colorations are audible as a bit of extra zing in the upper midrange. I'm going to try (reversibly) damping the platter as some changes I have tried as noted previously have not really been an improvement - they might have addressed an issue, but the medicine was far worse than the disease..
Anyway for all of the commentary I'm pretty happy with what I am hearing, and there is potential to go a lot further as resources permit.
Last edited:
Belt Noise
This morning I picked up some talcum powder and carefully removed the CB965 belt and applied it after listening to the drive train for a quick baseline. The belt noise is substantially reduced by this treatment which I guess is why Thorens recommended it in the first place.
It seems that the tighter/stiffer the belt the more the belt chatters as it goes around the circumference of the two pulleys. In the MKII the intermediate pulley is not well damped and rings badly due to this excitation. The talc seems to provide some lubrication between the belt and pulleys which allows the belt to run without chattering.
It's a good idea before reinstalling the "dusted" belt to make sure that there is as little loose talc as possible so it doesn't end up all over the inside of the turntable and potentially in the motor or main bearings.
I am not sure how long term this fix is, and I expect that at best it means periodic belt maintenance may be required.
This morning I picked up some talcum powder and carefully removed the CB965 belt and applied it after listening to the drive train for a quick baseline. The belt noise is substantially reduced by this treatment which I guess is why Thorens recommended it in the first place.
It seems that the tighter/stiffer the belt the more the belt chatters as it goes around the circumference of the two pulleys. In the MKII the intermediate pulley is not well damped and rings badly due to this excitation. The talc seems to provide some lubrication between the belt and pulleys which allows the belt to run without chattering.
It's a good idea before reinstalling the "dusted" belt to make sure that there is as little loose talc as possible so it doesn't end up all over the inside of the turntable and potentially in the motor or main bearings.
I am not sure how long term this fix is, and I expect that at best it means periodic belt maintenance may be required.
Belt Noise and Ongoing Tweaks
Ran the table continuously for more than 8hrs yesterday and am happy to report that noise levels did not increase and may in fact have decreased very slightly over the course of the day.
Design of a custom plinth will start soon.
Will attempt to minimally damp the platter from the bottom side if at all possible. (Depends on material thickness and clearance to components in the drive train.)
There is something organic to the sound that is hard to describe. I have never heard records sound better (prat, detail, imaging, sound stage, presence, noise floor, tonal balance, you-are-there presentation) in my current system or any prior system I have owned. Getting this vinyl playback thing right is not nearly as trivial as I thought, and I never really thought it was that trivial. (i.e. known good hardware automatically results in good sound if carefully set up. I now realize there is something more to it.) Having this finicky turntable has forced me to really focus on the details, and somehow everything on the table along with my arm and cartridge works synergistically to retrieve the maximum amount of musical "enjoyment" from the disk - not to mention a whole lot of things I have never even heard before. In some extreme instances it is almost like hearing another recording altogether, and it's FUN..
Ran the table continuously for more than 8hrs yesterday and am happy to report that noise levels did not increase and may in fact have decreased very slightly over the course of the day.
Design of a custom plinth will start soon.
Will attempt to minimally damp the platter from the bottom side if at all possible. (Depends on material thickness and clearance to components in the drive train.)
There is something organic to the sound that is hard to describe. I have never heard records sound better (prat, detail, imaging, sound stage, presence, noise floor, tonal balance, you-are-there presentation) in my current system or any prior system I have owned. Getting this vinyl playback thing right is not nearly as trivial as I thought, and I never really thought it was that trivial. (i.e. known good hardware automatically results in good sound if carefully set up. I now realize there is something more to it.) Having this finicky turntable has forced me to really focus on the details, and somehow everything on the table along with my arm and cartridge works synergistically to retrieve the maximum amount of musical "enjoyment" from the disk - not to mention a whole lot of things I have never even heard before. In some extreme instances it is almost like hearing another recording altogether, and it's FUN..
Your daily/semi-daily notes indicate good progress. It does take some time and tinkering before one gets really comfy with how well the project went on one of these models. Particularly on the first one. It is not an overly complex drive train, but does seem to have its fussy adjustments.
re: belts. They do stretch over time. The ones we think are too tight initially become less so in a month or two. Even so, it is disconcerting to find that 3 out of 3 belt suppliers offer belts for this TT with significant dimensional differences between them.
With that in mind, I'd have to admit that the good old days haven't really returned. For those of us still spinning vinyl in the 21st century, some amount of ingenuity is required to keep some part of the thing working.
But maybe that is part of the fun.
-Steve
re: belts. They do stretch over time. The ones we think are too tight initially become less so in a month or two. Even so, it is disconcerting to find that 3 out of 3 belt suppliers offer belts for this TT with significant dimensional differences between them.
With that in mind, I'd have to admit that the good old days haven't really returned. For those of us still spinning vinyl in the 21st century, some amount of ingenuity is required to keep some part of the thing working.
But maybe that is part of the fun.
-Steve
It continues to work well, so I am going to focus on running it as much as possible. The talc really seems to have done the trick as the table remains relatively and consistently quiet. Speed consistency is very good with no tweaks being required to the setting.
I will probably need to adjust the eddy current brake at some point as the restored turntable apparently has less friction induced losses than when built. It now runs a bit faster at any given setting of the eddy current brake and so is no longer centered at +/-3% when running at a nominal 33.33rpm.. The fact that the motor runs only warm to the touch after hours of use might tend to confirm this..
The belt plot thickens as yesterday I received a set of belts from a seller on eBay represented to be for the TD-124, right length, 0.025" thick, but only 0.125" wide.. They came with a nice note about how much money I had saved, unfortunately the fact that they are incorrectly designed for the table means I can't use them.. No savings in that, hopefully I can return them soon. Sadly they appear to be of good quality too...
All in all though I would say more than worth the trouble, and based on the ones literally coming out of the wood work around here I will probably be helping some friends to get their's going as well. It is a truly amazing feat for a designed engineered at the dawn of stereo to remain more than just relevant 53 yrs after its original commercial release..
Edit: Just heard from the belt seller, and he is going to ship me a pair of the correct ones. I'll report back on how they are..
I will probably need to adjust the eddy current brake at some point as the restored turntable apparently has less friction induced losses than when built. It now runs a bit faster at any given setting of the eddy current brake and so is no longer centered at +/-3% when running at a nominal 33.33rpm.. The fact that the motor runs only warm to the touch after hours of use might tend to confirm this..
The belt plot thickens as yesterday I received a set of belts from a seller on eBay represented to be for the TD-124, right length, 0.025" thick, but only 0.125" wide.. They came with a nice note about how much money I had saved, unfortunately the fact that they are incorrectly designed for the table means I can't use them..
No savings in that, hopefully I can return them soon. Sadly they appear to be of good quality too...All in all though I would say more than worth the trouble, and based on the ones literally coming out of the wood work around here I will probably be helping some friends to get their's going as well. It is a truly amazing feat for a designed engineered at the dawn of stereo to remain more than just relevant 53 yrs after its original commercial release..
Edit: Just heard from the belt seller, and he is going to ship me a pair of the correct ones. I'll report back on how they are..
Last edited: