The tool itself is made from a fiberglass resin rod, the modified screw driver shaft is intended to allow you to wedge the tool in the individual bushings, but I have found it simpler and more effective to drive them out rather than pulling. It worked rather well with the other bushings that do not fit, and with nylon bushings, but I suspect it would have some difficulty with these bushings if extraction was necessary.
Using my dial gauge I attempted to measure the bearing play from the platter edge, and what I saw was a change of about .003" of an inch at most and I am not entirely sure that some of that wasn't the platter itself. Zamac is not that stiff and the casting is pretty thin at the center so I suspect it will flex if you press on it hard enough. Let's put it this way it took more than a few pounds of force on the platter edge to get any indication at all. Fortunately it did return to a reading of 0 so I did not wreck the platter. I can't really recommend this test technique as I feel the possibility to damage the zamac platter is real. This platter will eventually get replaced with cast iron. The next change to this table will be an upgrade to the motor mounting to 124/II type with double bushings when I have sufficient dexterity to do the upgrade.
Using my dial gauge I attempted to measure the bearing play from the platter edge, and what I saw was a change of about .003" of an inch at most and I am not entirely sure that some of that wasn't the platter itself. Zamac is not that stiff and the casting is pretty thin at the center so I suspect it will flex if you press on it hard enough. Let's put it this way it took more than a few pounds of force on the platter edge to get any indication at all. Fortunately it did return to a reading of 0 so I did not wreck the platter. I can't really recommend this test technique as I feel the possibility to damage the zamac platter is real. This platter will eventually get replaced with cast iron. The next change to this table will be an upgrade to the motor mounting to 124/II type with double bushings when I have sufficient dexterity to do the upgrade.
As an aside I did not even have to adjust the speed when I put the table back together which is a clear indication that there was no significant change in spindle drag with the bearing change.
The bearings both stayed put when I reinserted the spindle/platter, a first.
I'd swear it sounds better too, probably self-suggestion, but this is a very happy machine.. lol Came back from the dead, some might have kept it as a parts unit, but I didn't - had to fix it at ridiculous expense. Having learned my lesson I have another which I am not going to restore, in fact many of the parts on this one came from that table.
The bearings both stayed put when I reinserted the spindle/platter, a first.
I'd swear it sounds better too, probably self-suggestion, but this is a very happy machine.. lol Came back from the dead, some might have kept it as a parts unit, but I didn't - had to fix it at ridiculous expense. Having learned my lesson I have another which I am not going to restore, in fact many of the parts on this one came from that table.
Kevinkr - thanks for the info. Sounds like you got a great result, & also sounds like the I.D. didn't change much, but the O.D. did. What, if anything, did you do with respect to the bushing oil? Leave it as is, Change to 3-in-one electric motor oil?
thanks. Interesting. Wonder if mine are dry as well. Haven't checked. Assumed they were loaded with whatever oilite uses.
This is my first post here on Diyaudio. I am a Norwegian playing around With vintage hifi Components, and I have been Lucky enough to find a TD124. I have been cleaning and lubricating according to information found in this tread and on other sites on the internet.
I have a spare motor I would like to rebuild, and I have ordered new bearings from Audiosilente in Italy. Last night I dismantled the motor, and I found that the motor coils/windings was loose. Is this normal, or should they be fixed in any way?
I have never seen loose coils/windings on any motor before, and would suspect that they could be vibrating under operation?
Are you using the same oil for the motor as for the main bearing?
I have a spare motor I would like to rebuild, and I have ordered new bearings from Audiosilente in Italy. Last night I dismantled the motor, and I found that the motor coils/windings was loose. Is this normal, or should they be fixed in any way?
I have never seen loose coils/windings on any motor before, and would suspect that they could be vibrating under operation?
Are you using the same oil for the motor as for the main bearing?
How loose are they? I think slightly loose is ok as I recall at least one of my motors has slightly loose windings, they don't really seem to have any influence on motor performance.
I use the same oil in all of the bushings, they're all sintered bronze types.. And as close to the original weight as possible.
I use the same oil in all of the bushings, they're all sintered bronze types.. And as close to the original weight as possible.
Eddy Current Brake Noise
Both of my TD-124 require the brake magnet to be in close proximity to the stepped pulley in order to maintain speed within a desirable range, wider spacings which result in quieter operation do not impose sufficient drag to keep the table running at the proper speed.
After some recent experimentation with externally imposed drag and a less aggressive brake setting I have decided to try 30wt non detergent motor oil in the main bearing to see if this will provide the additional drag I need in order to back off the brake setting to the point where the brake operates more quietly. Worst case I have to clean the housing drive the 30wt oil out of the bushings and reinstall 20wt oil..
I realized due to the significantly lower motor speed on 50Hz and the much higher belt tension due to the larger motor pulley required that available torque is probably 20% lower for 50Hz operation than for 60Hz operation. (Mechanical advantage of pulley ratio is about 17% greater for 60Hz operation) I have not heard of anyone in 50Hz countries having trouble with the table running fast, but it is a very common complaint here.
The other option is to reset the motor voltage tap to 125 - 150V which seemed the last time I tried it killed the dynamics. I am going to try this now and see what effect it has.
Both of my TD-124 require the brake magnet to be in close proximity to the stepped pulley in order to maintain speed within a desirable range, wider spacings which result in quieter operation do not impose sufficient drag to keep the table running at the proper speed.
After some recent experimentation with externally imposed drag and a less aggressive brake setting I have decided to try 30wt non detergent motor oil in the main bearing to see if this will provide the additional drag I need in order to back off the brake setting to the point where the brake operates more quietly. Worst case I have to clean the housing drive the 30wt oil out of the bushings and reinstall 20wt oil..
I realized due to the significantly lower motor speed on 50Hz and the much higher belt tension due to the larger motor pulley required that available torque is probably 20% lower for 50Hz operation than for 60Hz operation. (Mechanical advantage of pulley ratio is about 17% greater for 60Hz operation) I have not heard of anyone in 50Hz countries having trouble with the table running fast, but it is a very common complaint here.
The other option is to reset the motor voltage tap to 125 - 150V which seemed the last time I tried it killed the dynamics. I am going to try this now and see what effect it has.
It looks like the higher viscosity oil in the main bearing housing might be the better way to go.. My TD-124/II is running ok with the revised tap setting, my older TD-124 I noticed that the oem neon strobe lamp no longer illuminates on the 125 - 150V tap.
The 124/II is significantly quieter with the intermediate tap, but I still feel as though something is missing, it seems more laid back than I am used to. Perhaps the power of suggestion as it is running dead on speed right now and takes no longer really to come up to speed.
Autozone and Walmart locally both sell 30wt non detergent motor oil so I plan to pick some up tomorrow and give it a try in the older table first and if it works I will do the other and reset the tap to 100 - 120V. (My mains run about 116 - 117V in the evening when I do most of my listening and during the day may reach 120V)
The 124/II is significantly quieter with the intermediate tap, but I still feel as though something is missing, it seems more laid back than I am used to. Perhaps the power of suggestion as it is running dead on speed right now and takes no longer really to come up to speed.
Autozone and Walmart locally both sell 30wt non detergent motor oil so I plan to pick some up tomorrow and give it a try in the older table first and if it works I will do the other and reset the tap to 100 - 120V. (My mains run about 116 - 117V in the evening when I do most of my listening and during the day may reach 120V)
You've obviously not only restored the drive system, but also supercharged it!
Did a US version with the correct pulley ever exist?
Yes, all TD-124s from the factory were equipped with a dual pulley set up on the motor, the larger diameter pulley is for 50Hz, the smaller for 60Hz. The E50 motor has three taps: 100 - 120, 125 - 150, and 200 - 250V.
There was a single speed cost reduced version of the TD-124 known as the TD-121 for the US market that had a 60Hz/117V shaded pole induction motor based on the E50 with untapped coils, also had a smaller 10mm main bearing, no strobe or platter brake and a less expensive zamac platter. It was sold only for a year or two around 1963 time frame IIRC.
The TD-124 in all incarnations is quite common here, I own two in running order, and one parts unit. I have a number of friends who own at least one. The first ones were imported here in late 1957/58 time frame and I have worked on one with a serial # of just over 1000..
The TD-124 was brought to market with strong encouragement from the U.S. importer - it may be the case that without it, it might not have made it to production. I am not sure of the exact numbers but I suspect roughly half of the entire production of TD-124 were sold here in the USA. The hifi market was much bigger here in the U.S. in the TD-124's heyday than anywhere else for a variety of economic reasons including much lower taxes on luxury items. Garrard sold a lot of 301/401 here in the same time frame. Lenco was here too, but much more obscure than in Europe.Hello kevinkr
That brings up a question I've been wanting to ask for a long time:
Once the parts in a "parts unit" have been used up, can the empty chassis be purchased?
Sincerely,
Ralf
That brings up a question I've been wanting to ask for a long time:
Once the parts in a "parts unit" have been used up, can the empty chassis be purchased?
Sincerely,
Ralf
The problem with the speed you mentioned is not uncommon here because the motor is running faster at a higher mains voltage.
The mains here is about 230-235 Volt when you bring back the voltage to 210-220 the motor runs quiet with a normal speed regulation.
I'm going to take measurements on the E50 motor with 120 volts and 60 Hz.
volken
Sounds like we have the same problem then, I figured the lower torque available due to the lesser mechanical advantage might help in the 50Hz case, but apparently not.
I have generally had to run mine with the magnet about 1mm from the step pulley on both tables, changing to 30wt oil in one so far seems to have allowed me to both open up the distance to about 3mm and not set the brake for near maximum drag.
I am going to do the other one shortly. Note that this seems to be a win on several levels as the much noisier basket case 124 while not silent, is much quieter and this seems to have improved its reproduction quality without adversely affecting the energetic presentation I like about these tables.
I have generally had to run mine with the magnet about 1mm from the step pulley on both tables, changing to 30wt oil in one so far seems to have allowed me to both open up the distance to about 3mm and not set the brake for near maximum drag.
I am going to do the other one shortly. Note that this seems to be a win on several levels as the much noisier basket case 124 while not silent, is much quieter and this seems to have improved its reproduction quality without adversely affecting the energetic presentation I like about these tables.
Main Bearing Oil/Eddy Current Brake/Running too fast issue
I have been thinking about the brake noise issue for a while and the fact that I had 1mm or less of magnet to stepped pulley clearance and the thing cranked almost all the way slow in order to get the speed correct on both of my tables.
Both tables have good unworn main bearings.
I changed out the 20wt oil in the bearing and replaced it with 30wt Non-Detergent motor oil I purchased at a local Auto Zone. I have now done this in both tables.
I have been able to back off the magnets to about 3mm and run them closer to centered when warm than before the lubricant change. The eddy current brakes are significantly quieter on both tables.
The tables also achieve speed stability much more quickly, not sure why at this point in time.
The most interesting thing is the apparent improvement in sound quality which I did not expect at all. Both tables seem to have picked up some additional low level/background detail, and the sound is a bit tighter/cleaner overall. Something has been removed, and I suspect that is some vibration propagated through the chassis from the overworked brake.
I would recommend this change to anyone running a TD-124, but note that it is important for the life of the oilite bearing that you find non detergent motor oil, I can't vouch for the long term effect of some additives on the performance of the bearing.
I'm probably understating the improvement to some degree, but am also not aware of any deficits either.
For the time being I would stick with 20wt electric motor oil to lubricate the motor and other bushings in the table.
I have been thinking about the brake noise issue for a while and the fact that I had 1mm or less of magnet to stepped pulley clearance and the thing cranked almost all the way slow in order to get the speed correct on both of my tables.
Both tables have good unworn main bearings.
I changed out the 20wt oil in the bearing and replaced it with 30wt Non-Detergent motor oil I purchased at a local Auto Zone. I have now done this in both tables.
I have been able to back off the magnets to about 3mm and run them closer to centered when warm than before the lubricant change. The eddy current brakes are significantly quieter on both tables.
The tables also achieve speed stability much more quickly, not sure why at this point in time.
The most interesting thing is the apparent improvement in sound quality which I did not expect at all. Both tables seem to have picked up some additional low level/background detail, and the sound is a bit tighter/cleaner overall. Something has been removed, and I suspect that is some vibration propagated through the chassis from the overworked brake.
I would recommend this change to anyone running a TD-124, but note that it is important for the life of the oilite bearing that you find non detergent motor oil, I can't vouch for the long term effect of some additives on the performance of the bearing.
I'm probably understating the improvement to some degree, but am also not aware of any deficits either.
For the time being I would stick with 20wt electric motor oil to lubricate the motor and other bushings in the table.