Yes I used 3 in 1 blue bottle electric motor (SAE20) The motor, rotors and laminations were all pretty clean and no outward signs of oil dripping down onto them, no build up. I really think the top sintered bushing from Simone absorbed the oil from the pads. I can't come up with another explanation.
To reassemble my 2nd tear down I cut strips of business card .014" thick and used them as spacers in the rotor, in hopes of better alignment. This worked pretty good and I only needed very slight adjustment to get RPM's up to 1744. I let it run for 12 hours yesterday. Temps are still in the 130's F. Simone says there are hot motors (they run near 60C) and cool motors (around 48C). I have a hot one. Today I may finish assembly, put in the old stock plinth with new mushrooms from Simone and play my first record with this table. I'll run the original idler first to get a sense of its sound before switching to Simone's idler. I am also toying with the idea of using a 40mm very quiet PC/server fan, run from a linear PSU inside the plinth to cool the motor a bit, does that idea carry any merit. Fan will only output 12db of noise.
I'm also looking to replace the stock SME 3009 ser 2 improved arm. I've narrowed it down to Audiomods Classic V or Sorane SA-1.2.
To reassemble my 2nd tear down I cut strips of business card .014" thick and used them as spacers in the rotor, in hopes of better alignment. This worked pretty good and I only needed very slight adjustment to get RPM's up to 1744. I let it run for 12 hours yesterday. Temps are still in the 130's F. Simone says there are hot motors (they run near 60C) and cool motors (around 48C). I have a hot one. Today I may finish assembly, put in the old stock plinth with new mushrooms from Simone and play my first record with this table. I'll run the original idler first to get a sense of its sound before switching to Simone's idler. I am also toying with the idea of using a 40mm very quiet PC/server fan, run from a linear PSU inside the plinth to cool the motor a bit, does that idea carry any merit. Fan will only output 12db of noise.
I'm also looking to replace the stock SME 3009 ser 2 improved arm. I've narrowed it down to Audiomods Classic V or Sorane SA-1.2.
If the bushings from Audiosilente are not already impregnated with lube, the oil that you put into the upper motor bushing will drizzle down and out of that bushing due to the force of gravity. So in practice it becomes necessary to routinely re-lube that upper bushing from time to time. Otherwise it runs dry.
Another thing to check: were the original bushings really all that worn out? I have a background in machining and also mechanical inspection. So measuring stuff precisely is my thing. And my opinion, after working on several E50 motors, is that it may be advisable to simply clean the old bushings, clean and dress the rotor shaft, then re-lube and assemble. The motor may offer better running performance this way than with new bushings that reduce the running clearance between bushing wall and shaft.
Adding to this I might add that some of these motors have come to me with the nickle plates that comprise the central structure of the motor, showing signs of warp. When this happens it becomes more of a chore to achieve adequate alignment between upper and lower bushings.
This motor needs a redesign, I think. We need to build a better E50.
-Steve
Another thing to check: were the original bushings really all that worn out? I have a background in machining and also mechanical inspection. So measuring stuff precisely is my thing. And my opinion, after working on several E50 motors, is that it may be advisable to simply clean the old bushings, clean and dress the rotor shaft, then re-lube and assemble. The motor may offer better running performance this way than with new bushings that reduce the running clearance between bushing wall and shaft.
Adding to this I might add that some of these motors have come to me with the nickle plates that comprise the central structure of the motor, showing signs of warp. When this happens it becomes more of a chore to achieve adequate alignment between upper and lower bushings.
This motor needs a redesign, I think. We need to build a better E50.
-Steve
Mostly these motors are good for another 40 years if cleaned and relubed. If there is no obvious play in the bearings they often are better than any other option. 90% are likely to be usable. Don't be put off by what you see. They are made to very tight limits. If unusable often they look oval. The coils if giving a measurement for resistance are likely to be good as new. Strictly speaking inductance is what we need to know. However the DC resistance says the coil is as it should be. A crude test which should be reliable. Any DC resistance change will be an inductance change. If the DC resistance is calculated at 230/115V it will show a vastly higher power use than is reality. The inductance can be calculated from that if the VA known. Very low DC resistance will show a faulty coil as will excessive heat. That would be when coil sections fuse together.
The motor coming to speed in 10 to 20 minutes is typical. This type of motor approximates to a constant speed when warm and at a light load. The result is less vibration over synchronous types. Unlikely to cog. Original bearings with the right oil will be a good mix. The harmonic distortion of the motor current waveform is about -50dB or better. A Linn Airpax motor - 25 dB or worse. This is due to motor type. The Airpax has just enough torque to work, the TD124 has surplus torque.
The motor coming to speed in 10 to 20 minutes is typical. This type of motor approximates to a constant speed when warm and at a light load. The result is less vibration over synchronous types. Unlikely to cog. Original bearings with the right oil will be a good mix. The harmonic distortion of the motor current waveform is about -50dB or better. A Linn Airpax motor - 25 dB or worse. This is due to motor type. The Airpax has just enough torque to work, the TD124 has surplus torque.
"the nickle plates that comprise the central structure of the motor, showing signs of warp"
I only have a basic micrometer so measuring to your level is above my equipment. New bearings already installed. Simone says his bearings are prelubed. 7 days, 90 hours and my top felts were almost dry. Motor rotor and lamination section appeared clean and free of oil residue. I really think the bearing sucked the oil from the felts. I have very slight warp in my lamination, but was able to align to hold 1743/1744 RPM's. I am pleased with the alignment. I was also very surprised how little vibration this rebuilt motor has. I am suspending it with MK2 posts and 2 sorbothane grommets per post, used to hold a PC board and reduce vibration. I had them and tried, northing to lose, I am very impressed. I also have the spring set in the wings to try. I agree a new improved E50 would be at the top of most 124 owners wish list. It works, dang hot though.
The step pulley, like most, is the noise maker (I have gen 1 shaft on chassis). Today I installed 4mm ceramic bearing, and a drop or two of Phils (wood) tenacious oil (used for bicycling). Shaft is polished and bearing has no play. I also installed Simone's Idler wheel, ground round version and his belt. Very quiet. With needle on record, no rotation, I can hear soft mechanical noise if my ear is right by my midrange drivers. I am using a SME 3009 S2 imp. arm with a very cheap AT3600L cart the previous owner got right before he sold the table. I think with a better arm and cart. this rig will come close to my reference SME30mk2 I owned for 20 years. Its sounding very good with that cheap AT cart now, shockingly good.
I only have a basic micrometer so measuring to your level is above my equipment. New bearings already installed. Simone says his bearings are prelubed. 7 days, 90 hours and my top felts were almost dry. Motor rotor and lamination section appeared clean and free of oil residue. I really think the bearing sucked the oil from the felts. I have very slight warp in my lamination, but was able to align to hold 1743/1744 RPM's. I am pleased with the alignment. I was also very surprised how little vibration this rebuilt motor has. I am suspending it with MK2 posts and 2 sorbothane grommets per post, used to hold a PC board and reduce vibration. I had them and tried, northing to lose, I am very impressed. I also have the spring set in the wings to try. I agree a new improved E50 would be at the top of most 124 owners wish list. It works, dang hot though.
The step pulley, like most, is the noise maker (I have gen 1 shaft on chassis). Today I installed 4mm ceramic bearing, and a drop or two of Phils (wood) tenacious oil (used for bicycling). Shaft is polished and bearing has no play. I also installed Simone's Idler wheel, ground round version and his belt. Very quiet. With needle on record, no rotation, I can hear soft mechanical noise if my ear is right by my midrange drivers. I am using a SME 3009 S2 imp. arm with a very cheap AT3600L cart the previous owner got right before he sold the table. I think with a better arm and cart. this rig will come close to my reference SME30mk2 I owned for 20 years. Its sounding very good with that cheap AT cart now, shockingly good.
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One not so obvious reason for the heat of the motor is in its design. It is a shaded pole motor and has 4 copper loops around the 'corners' of the stator. These are 'shorted turns' and provide the necessary phase shift to provide the rotating magnetic field. A side effect of the copper shorted turn is the wasted energy being turned into heat
The Phil Woods Tenacious Oil is, iirc a chain lube for bicycles. I've used that in the past. I really think it might be wrong for the step pulley axle and for the idler wheel axle. RPM's might be too high for that type of lube. Just go with regular 20 wt turbine oil.
Good to know that Audiosilente pre-lubes these bushings.
Over the years I have modified my bushing alignment process. With my early units I used a scrap of info I found on a Japanese site that described listening to the motor with a stethoscope while making minute adjustments between upper and lower bushings in order to achieve best possible coaxial alignment between them. Since then I have found it is far simpler to achieve optimal alignment simply by holding the motor in my hands and adjust until I get the longest spin-down times. And this is simply spinning the rotor between thumb and fore-finger. Finger spin, if you will.
With regard the warped core plates about which I wrote of earlier, I have seen several motors with very slight evidence of warped plates but one motor where the plates were severely warped. And even this motor was able to be aligned for acceptable operation. And that motor did perform well.
With regard to Nigel's comments about 10 to 20 minute warm up period before stable speed is reached. I can say that it is possible to get the E50 to start up from cold and achieve closer than 1% of 33-1/3rpm within the first 'platter' rpm. And under its own power. However I have noticed that these units will over a period of 10 minutes or so achieve ultimate stability and stay that way for the rest of the listening session. However, room temperature plays its part. The difference between winter and summer performance. All very slight but it is there.
Of course I'm on 60 hz power at my location. I use a large variable output transformer to adjust output voltage to my Td124. Currently it is operating on 105 vac and seems happy right there.
Another thing worth noting. These TD124 players come with a neon lit strobe and one can't help but pay attention to it. Meanwhile, these motors, apart from external difference in case design, are of the same design as those used on the Garrard 301 and 401. I suspect that owners of the Garrard models have spent less time worrying about speed accuracy simply because their units did not have working strobes, or those that had the strobe patterns on the exterior of the platter were set to report to 50 hz and never 60 hz, so in the USA no one paid attention to speed accuracy of those units.
-Steve
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The speed is usually about 0.3% out cold to hot. By the time a cup of coffee is made the speed is about 0.1% out. Over the next hour it reaches 0%. The heat as rightly said is caused by the shorted copper bars inside the motor. The speed relates to how the oil thins.
The very low harmonic distortion shown in the current waveform says why the vibration is so low. Also it is mainly second harmonic which is ideal. The graph is the Garrard 501 which gives similar results. The 501 uses a pure sine wave at 120 to 240 VAC ( 33 to 120 RPM ). It uses a 50 watt amplifier and SVF oscillator.
This below is the 1 watt LP12 motor. High levels of third harmonic which will cause vibration.
This is a mildly sucessful TD124 filter. The mains is worse. The third harmonic is mains rather than motor. This is a real TD124 in use. It says 401 which isn't correct. It was a 124 project. I borrowed one from Loricraft.
This is the mains electricity before the filter. Most of you will have the same. Graph two and three are the ones to look at.
The very low harmonic distortion shown in the current waveform says why the vibration is so low. Also it is mainly second harmonic which is ideal. The graph is the Garrard 501 which gives similar results. The 501 uses a pure sine wave at 120 to 240 VAC ( 33 to 120 RPM ). It uses a 50 watt amplifier and SVF oscillator.
This below is the 1 watt LP12 motor. High levels of third harmonic which will cause vibration.
This is a mildly sucessful TD124 filter. The mains is worse. The third harmonic is mains rather than motor. This is a real TD124 in use. It says 401 which isn't correct. It was a 124 project. I borrowed one from Loricraft.
This is the mains electricity before the filter. Most of you will have the same. Graph two and three are the ones to look at.
I liked the Phil's oil because I thought it was thicker than the 3 in 1 SAE20 and specifically was for metal to metal. I don't think phil's has additives like many other oils do. It has mostly worked so far and with the audio silente belt and idler it is pretty quiet, more so than the day before with a cheap replacement belt and the OEM idler wheel. I am certainly open to using the 20SAE, for this application.
My motor takes about 2 minutes to really have stable platter speed, then is it rock solid. I set it just a touch fast and watched when I put the needle down and it stabilized and stopped moving so friction of needle does have some effect.
I am heading to northern Michigan tomorrow for a 10 day trip. System is unplugged and waiting for my return, I'll miss my music. BTW, I love the clutch. I wasn't sure how I would like it but using it is really easy and just works. Before this I have owned SME 30mk2, SME20MK2, Pink triangle ? can't remember model, looked a bit like a Linn, and of course the Linn LP12 none of those had a clutch.
My motor takes about 2 minutes to really have stable platter speed, then is it rock solid. I set it just a touch fast and watched when I put the needle down and it stabilized and stopped moving so friction of needle does have some effect.
I am heading to northern Michigan tomorrow for a 10 day trip. System is unplugged and waiting for my return, I'll miss my music. BTW, I love the clutch. I wasn't sure how I would like it but using it is really easy and just works. Before this I have owned SME 30mk2, SME20MK2, Pink triangle ? can't remember model, looked a bit like a Linn, and of course the Linn LP12 none of those had a clutch.
I agree, I never used it much for the bike unless I was riding in really bad weather, it's perfect your your weather. I'd have chatter from that dang step pulley put a drop drown the bronze shaft with PW Tenacious and immediately it quieted down. My experience with it for this use is very short term though. The step pulley has been quiet the last 6 hours of listening with ceramic BB, Audio Silente belt and that one drop of Phil's.
Best of my recollection is that Audio Silente makes a replacement bearing for the original intermediate pulley. Replacing it would require some precision jigs be made up.
On the subject Nigel has raised about power quality, etc. I designed and built a single phase drive for one of mine using a synthesized source and filters with LM3880A in parallel to a step up transformer. I run that E50 at approximately 110V.. Distortion of the waveform is much less than on the mains here, which look a lot worse than the waveform Nigel presented. (Mine is a trapezoid of around 175Vpk most of the time.)
The Papst runs on a Siemens Micromaster 420 3 phase VFD modified for sinewave output via a custom filter not of my design. The Papst exhibits better speed stability and is somewhat quieter than the E50. (Fan noise notwithstanding LOL)
The MKII/E50 is equipped with a prototype arm and panasonic strain gauge, the 124/Papst is equipped with a Jelco TK-850L, HS30 shell and a Mutech Hayabusa. Electronics are all of my design.
It's the end of the vinyl era here so I am not geared up nor am I particularly interested in doing any measurements. (maintenance mode only now - I will run these until they break and then figure out what if anything to do about it)
Mostly digital now and some tape. (I have a Studer A810) Vinyl is about 5% of what I listen to these days.
On the subject Nigel has raised about power quality, etc. I designed and built a single phase drive for one of mine using a synthesized source and filters with LM3880A in parallel to a step up transformer. I run that E50 at approximately 110V.. Distortion of the waveform is much less than on the mains here, which look a lot worse than the waveform Nigel presented. (Mine is a trapezoid of around 175Vpk most of the time.)
The Papst runs on a Siemens Micromaster 420 3 phase VFD modified for sinewave output via a custom filter not of my design. The Papst exhibits better speed stability and is somewhat quieter than the E50. (Fan noise notwithstanding LOL)
The MKII/E50 is equipped with a prototype arm and panasonic strain gauge, the 124/Papst is equipped with a Jelco TK-850L, HS30 shell and a Mutech Hayabusa. Electronics are all of my design.
It's the end of the vinyl era here so I am not geared up nor am I particularly interested in doing any measurements. (maintenance mode only now - I will run these until they break and then figure out what if anything to do about it)
Mostly digital now and some tape. (I have a Studer A810) Vinyl is about 5% of what I listen to these days.
It shows the actual vibrations of a Garrard 501 motor fed from a very low distortion amplifier ( Like HH MX 1200 in topology, Hitachi design circa 1979 ). The other graphs show how this is badly changed by mains electricity. Somehow stop using mains electricity is the answer ( not easy ). What you see is proportional to vibration. The voltage is measured through a small resistance in series with the motor. Very risky for yourself and the computer if you get it wrong. The 501 probably is 20 dB quieter than the TD124 ( factor of 10 ). Half of that is the giant size of the motor needing less current for a given torque. The rest is the regenerator PSU. It has been measured at -79dB. From memory TD124 is about -58 dB. I would imagine -66 dB is possible. Most LPs will not better that.
The Linn LP12 had an excellent amplifier in the Valhalla. Alas the motor did nothing with it except make it the same day to day.
My third graph shows how a passsive filter much like a subwoofer filter is only semi sucessful. The wave looks nice so worth a try. Higher harmonics are still there. It gets hot. No worse than a class AB amplifier. In the UK it is easier to do as we have 240 Vrms which can be reduced to 115 Vrms. Calculations are tricky as the motor inductance is partly what influences the filter. I used a Variac to keep things safe. The inductance is helpful if wondering as it limits higher harmonics.
The final graph is typical mains. It's like drinking river water. Not ideal. If the problem is removed a stiffer bellt could be used. That would give more punch.
Thanks for that follow-up. With regard the plot posted above, I gather that the spikes describe the dominant character of the noise I'd hear if holding a stethoscope to it. The part that gets through the grommets somewhat filtered out and flows into the cast chassis.
Yes, the quality of mains water could flow smoother than it does. I gather it takes more than just a large transformer to smooth out what flows into our systems.
Any chance we could take a look (nice photo) of a 501 motor?
-Steve
I didn't find the built up motor yet. I did find this. During Lockdown I was so bored I took the least suitable idea I could think of and made it work. Usually fire is the result when this brave/stupid. It's the 1970s PW Texan/PE Rondo/Rega Brio. It is an op amp plus an output stage with gain. The latter is a No No. The next No No is to make it run from a 50 VA Meanwell SMPS. The residuals are mostly due to that. Adding feedback required some lateral thinking. The seemingly redundant 1 uF class X2 in red made it more stable. The parts are mostly what I had many of. Use better ones if you want trouble. I seem to remember I simplified this a little. Sorry to say that file is a bit lost also. It was a simplified and quieter centre voltage at +22.7VDC. 177Vrms AC is for 78 RPM.
More remarkable is this one off is point to point. Doubtless a PCB would change something. Sorry to say you are on your own if you try this. A Velleman kit amp lasted ten seconds on the same. A six volt transformer might work better for TD124. The gain of the output pair is about right like this. 120R + 39R sets it. I use the original Texan idea for that. I did use a Garrard 401 ( my own ).
The output is shown as a voltage graph. As I know tthe motor it's enough. The input wasa SVF oscillator from the Analogue electronics cookbook. I used LED stabilizers. The biasing works just well enough and prevents trouble. 82R x 3. A Paul Kemble web page - PW Texan amplifier and the PE Rondo.
More remarkable is this one off is point to point. Doubtless a PCB would change something. Sorry to say you are on your own if you try this. A Velleman kit amp lasted ten seconds on the same. A six volt transformer might work better for TD124. The gain of the output pair is about right like this. 120R + 39R sets it. I use the original Texan idea for that. I did use a Garrard 401 ( my own ).
The output is shown as a voltage graph. As I know tthe motor it's enough. The input wasa SVF oscillator from the Analogue electronics cookbook. I used LED stabilizers. The biasing works just well enough and prevents trouble. 82R x 3. A Paul Kemble web page - PW Texan amplifier and the PE Rondo.
http://artduson.com/images/magazines/garrard-audio-2015-09-as-good-as-it-gets.pdf
If you can wade through this it's all shown. My two 501 motors I have don't have the pretty bits on.
If you can wade through this it's all shown. My two 501 motors I have don't have the pretty bits on.
thanks again for those additional posts. With the 3rd harmonic spike at -68 db that's gotta be a quiet running 501 motor. Power supply is important.
I've been looking for some photos of a 501 motor and have only found a few, one of which is in the document you link. Not much out there. I presume it to be strongly related to the 301/401 design. And so I've russled up a photo or two of a 301 motor. What I find indicates a different sort of outer casing. when compared to the E50. And that is what I want to do here. To compare the E50 to other shaded pole motors such as that on the 301.
Just looking at the externals it would seem that the 301 motor has a much more robust case work surrounding its rotor. And the casework holds the entire works, the upper and lower bearings as well as the core plates. All of it. And isn't the spring isolation design worthy of serious study..!
The E50 makes use of its 'core plate stack up' structure in that the core plates serve not only for the electro-magnetic function, but also to support and hold the rest of the motor architecture. The plate stack becomes a stressed member.
So my curiosity has me wanting to make comparisons between the two different motors with regard to operational characteristics. How much each is effected by temperature, room temperature, for instance.
-Steve
I've been looking for some photos of a 501 motor and have only found a few, one of which is in the document you link. Not much out there. I presume it to be strongly related to the 301/401 design. And so I've russled up a photo or two of a 301 motor. What I find indicates a different sort of outer casing. when compared to the E50. And that is what I want to do here. To compare the E50 to other shaded pole motors such as that on the 301.
Just looking at the externals it would seem that the 301 motor has a much more robust case work surrounding its rotor. And the casework holds the entire works, the upper and lower bearings as well as the core plates. All of it. And isn't the spring isolation design worthy of serious study..!
The E50 makes use of its 'core plate stack up' structure in that the core plates serve not only for the electro-magnetic function, but also to support and hold the rest of the motor architecture. The plate stack becomes a stressed member.
So my curiosity has me wanting to make comparisons between the two different motors with regard to operational characteristics. How much each is effected by temperature, room temperature, for instance.
-Steve
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