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  »  New  The Foolishness of Analog People..  Late to the discussion but cannot resist...  Analog Playback Forum     56  559970  01-30-2006
  »  New  Micro RX 5000..  Alternative method...  Analog Playback Forum     9  66188  11-09-2008
  »  New  Micro RX5000: is that bearing spins normally?..  How many turns do the good bearing......  Analog Playback Forum     7  39820  02-03-2014
  »  New  Fetish of Micro's?..  Size of ceramic ball...  Analog Playback Forum     122  370104  10-29-2017
10-29-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017

Post #: 81
Post ID: 24518
Reply to: 24502
Fetish of Micro's?
Interesting to see your different opinions also regarding the complementary inertia options.
Again, I'm touched in this subject because of HS-80 which no question is sexy but with it unfortunately I didn't have chance to set up the stable speed on my neither RX-5000.
I got the best result when I mounted back the original SF-1 belt to the platter and K thread to flywheel.
The speed is accurate and stable (with belt or thread) just when I get rid of the HS-80.

Probably influenced also by my fetish to Micro's I was decided to build an RX-5000 system with tonearms and cartidges from the same eras.
Still I'm on the way so I really like to read your experiences (also in other threads) regarding RX-5000 even if some of them are contrary but this is common in our hobby...

Probably will be long but I hope not never ending project and finally I can compare it with my current main Michell Orbe/SME V/VdH Grasshopper II combination which I like very much and represent a totally different school.

Jam, I follow your path and I keep one RX untouched and the other one I dedicate to experiments.
Please describe your ideas regarding bearing and power supply tweaks.
As I'm not really professional so the electronic schematics would be really helpful.

Thanks a lot!
10-29-2017 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,049
Joined on 05-28-2004

Post #: 82
Post ID: 24519
Reply to: 24518
Be carefully.
 measet wrote:
unfortunately I didn't have chance to set up the stable speed on my neither RX-5000. I got the best result when I mounted back the original SF-1 belt to the platter and K thread to flywheel. The speed is accurate and stable (with belt or thread) just when I get rid of the HS-80. 

If your RX-5000 has no stable speed then do not “cure” is with HS-80.  Fix the bearing and motor of your RX-5000. A properly operating RX-5000 should give you speed stability that it will never be a factor of your worry. It is not as perfect and some supper duper contemporary electronic stabilized TTs but it is enough not to be concerned about it.
 measet wrote:
Probably influenced also by my fetish to Micro's I was decided to build an RX-5000 system with tonearms and cartidges from the same eras. 
 Find another hobby them as to cultivate the Micro fetish is not healthy things to do. A TT is just a tool for getting something ease. If you willing to dedicated your to cultivating tools then it is up to you but be advised that Micro did not bold good tonearms and cartridges.



"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
10-30-2017 Post does not mapped to Knowledge Tree
Stitch


Behind The Sun
Posts 235
Joined on 01-15-2009

Post #: 83
Post ID: 24521
Reply to: 24519
Motor
The motor can't hold the specs forever.  
When you have drift it is time to replace some parts, a qualified technician will know what to do. You can find information in the web to open it correctly.
The spindle needs some oil also (same for HS-80). You have to open it for this. The motor itself drives platter + HS-80 easily.
It will not work with SX-5000 motors (with string), they are totally different, they work with inductivity and are too weak for that. Air bearing does not need strong motor.




Kind Regards
Stitch
10-30-2017 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,049
Joined on 05-28-2004

Post #: 84
Post ID: 24522
Reply to: 24518
Some ideas....
 Stitch wrote:
The motor can't hold the specs forever…..The motor itself drives a HS-80 easily.
 Yes, and no. When people talk about it they forget to note that it is not a motor problem most of the time but the interface between platter and motor. The tension of belt (tape, string or whatever you use) between the motor and platter is a very key and it is high neglected subject. One person loves to have high tension belt between motor and platter, another love to have high tension connection between motor and platter, use high power motors with a lot of logic in motor drive, other person use super light belt that literary slips over the platter and no brain in motor… there are many scenarios available in it but generally if you have a very light tension between motor and platter then the motor will live longer then you do.
 
I personally drive my motor VERY light and my belt is dried by cover with baby powder and hands very loosely. Interesting that my belt does not sit on the side of the platter but run over the indentation at the very top of the platter, where the platter diameter is smaller. I feel that running a smaller diameter mage the gyroscope effect of the platter much stronger. The disadvantage is that it take a while to speed to stabilize. Still with the mass of the platter and the lightness of the belt tension the belt does not really drives the palter but just compensates the loss of inertia… 
 measet wrote:
I didn't have chance to set up the stable speed on my neither RX-5000. 
Measet, one more tip I would like to pass to you. Do you have a Cat in home? If you do not them you need to get one. Anyhow, for whatever reasons Cats find the air pipes to Micro pneumatic suspension is very attractive and they sometimes bite the air pipe. If they do then the pipe might have a very-very minor leak, you will not be able to see or hear it but it will drop the air suspension pressure and will affect the disk stability. So, what you need to do it to make the testing. Here is how I do it. Run you TT at 33RPM and then remove the belt, presumably it hangs lightly. Then measure how long time it will take the platter to have completely stop. Let presume that it take 5.5 minuts. Then take you air pump, connect it with a new very short air pipe and do the same experiment. If you have shorter time that take platter to stop them you main air pump is compromised. I have a pipe connector that I switch to test my pipes. I do not do it lately as nowadays my air pile are wrapped I past the only reasons why I have problem with stability is because my Cats eat my pipes. Below are a few link that you will fine useful.
 
https://www.amazon.com/gp/product/B071NNNWVH/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1
 
https://www.amazon.com/gp/product/B01MFX7LBP/ref=oh_aui_detailpage_o09_s02?ie=UTF8&psc=1
 


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
10-30-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 85
Post ID: 24523
Reply to: 24522
Rebuild
Measet,
The bearing oil on the RX-5000 should be replaced with a good low viscosity turbine oil, Zoomspark works well. When opening the bearing you will notice there is a steel thrust plate that will have a dimple on it, you can flip around and use the other surface if you wish. The ball is white ceramic which I replaced with a Silicon Nitride ball (that is also an option). Replace the O-ring seal. The rebuild has to be done by someone that is experienced.
The electrolytic capacitors in the motor control boards should be replaced as some of them will eventually fail causing speed problems, remember these components are more than 30 years old. The motor itself should be cleaned and lubricated. This also should be performed by someone qualified.
Performing these steps should extent the life of the turntable for a long time.
I am working on a power supply upgrade for the motor, initial results are promising but it will take several months to complete.
10-30-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 86
Post ID: 24524
Reply to: 24523
PIC1
PIC1
10-30-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 87
Post ID: 24525
Reply to: 24524
PIC2
PIC2
10-30-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 88
Post ID: 24526
Reply to: 24525
PIC3
PIC3
10-30-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 89
Post ID: 24527
Reply to: 24526
PIC4
PIC4
10-30-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011

Post #: 90
Post ID: 24528
Reply to: 24527
Get the lead out?
I have not opened my bearing yet to change the oil, following the philosophy of “if it ain’t broke, don’t fix it”. It’s a different situation here than a car’s oil. The seals prevent the oil from being exposed to oxygen, moisture and other contaminants, maybe not perfectly for 30 years though. There is no degradation from heating cycles such as in a car. Some of the more volatile components in the oil could have evaporated, even through good seals after 30 years, though. My seals show no leakage, but if they did, the situation would be more dire.  But Jam may convince me to change my mind.

A caution: Micro Seiki used lead-powder in their oil. The dark oil that you see in the bowl in Jam’s picture is therefore quite toxic. I’m betting that the dark color is not due to bearing wear. Use vinyl gloves and a disposable bowl. Then there is the question about whether or not to add lead powder to the new oil. Micro Seiki didn’t add the lead just to make it toxic; they had a reason. Some say it adjusted the viscosity, while others say it filled the tightly-machined voids. I do not know, but its use was certainly intentional.

Here is a snippet from an Audiogon post:

“Micro-Seiki used lead (Pb) "powder" in their oil -- it is very toxic, and should be handled with care. Before you go through the exercise of removing the oil and changing it, you should listen to bearing housing base with a stethoscope -- if the bearing moves freely,and is not noisy, just use it as is. Otherwise you will need to replicate the same original treatment - and use powdered lead (Pb) [available here - www.testbourne.com/materials/metals-details/3523-640/Lead-powder/ ] in your replacement oil. This is due to the spacing in the bearing, and I am not sure if graphite powder would be a good substitute, as graphite might etch or corrode the stainless steel -- whatever you do, use a "high molecular weight" oil -- or an impregnated one.”

A Google search will turn up other references to the lead situation, no doubt.

Finally, a lot of people seem to think that the test of an ideal bearing of this type is that it exhibits zero friction. That is not necessarily desirable. It is possible that some SMOOTH friction (not “scratchy”) that is  created mostly by oil viscosity would damp angular (rotational) resonances. It would also load the motor slightly, which could be beneficial (or not). Also, as I recall, this bearing had some sort of pumping mechanism that circulates oil to keep the upper parts lubricated. I’m not sure about that though. That pumping action, if it is working properly, adds more viscosity friction due to the work required to pump the oil.  It is theoretically possible for an underfilled bearing to show lower friction (at least in the short term) since oil cannot be pumped. So there is a lot of uncertainty and some conjecture here. My real point is that changing the oil brings up new concerns.

Jam, do you have insights into any of these points? Did you see any grooves inside the housing to indicate an Archimedes-screw-type oil pump or any other pumping means besides capillary action?


______________
Brian
10-30-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011

Post #: 91
Post ID: 24529
Reply to: 24528
It’s in the manual
The MS manual itself describes the lead in the oil and the desirable effect of significant viscosity on damping rotational resonances:
https://www.vinylengine.com/ve_downloads/index.php?micro_seiki/micro_seiki_rx-5000-ry-5500.pdf
(You may have to log in to retrieve this manual)


______________
Brian
10-31-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 92
Post ID: 24530
Reply to: 24529
Bearing
Wellington,
It is my understanding that lead was used because it'a anti an anti-seize properties. The bearing fit is very tight and I suppose this helped with the lubricants of the period and is not a problem with modern synthetics.
The bearing does not have a spiral grove machined on it's surface, the whole assembly is filled with lubricant .
I have tried oils of different viscosity and found the low viscosity ones work best, there is no play in the bearing at all. If I spin the platter as fast as I can manually and release(no belt) it will spin in excess of six minutes before coming to rest.
I only see the need for high viscosity lubricants for loose fitting bearing. Higher viscosity means more torque required by the motor and the attendant increase vibration, and so on. 
The Feickert turntables (inverted bearing) just replaced their bearing lubricant with a lower viscosity one with was an improvement. A great turntable by the way but definitely no Micro-Seiki. I have tried a lot of turntables and the RX-5000 rules and the only turntable I think (That I have heard)  is better is the American Sound but that is another story................
10-31-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 93
Post ID: 24531
Reply to: 24530
PIC
PIC
10-31-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011

Post #: 94
Post ID: 24532
Reply to: 24531
No seizures
Jam,
Yes, as I now see, you are right that the bearing was merely filled to the rim with oil and that it doesn’t have a pump feature (like some older turntable bearings did). And yes, the lead is touted for anti-seize (mostly copper these days), but also I read it was used for wear-reducing and friction-reducing. I guess these are similarly-derived benefits. It was more commonly used in industry than I knew. It was largely abandoned due to its not being environmentally friendly (to say the least) and very toxic, than it was for any lack of performance. Some have replaced it with graphite particles with the same hoped-for mechanisms in mind. Apparently when tight-fitting metal surfaces squeeze the oil film out of the way, the lead particles remain in the microscopic gap and act as soft ball bearings in a microscopic sense.

From the 5000’s manual: “Furthermore, there is an impressive damping effect [of the oil bath] to combat the resonance which is generated as the platter rotates, and the total signal-to-noise ratio is also improved.” The 5000’s brochure says it similarly: “An oil bath system is featured between the shaft and bearing and since this is full with oil, there is no fear that the oil will run out, [sic] the resonance which accompanies the rotation of the platter is superbly damped down, and the total signal-to-noise ratio is improved.” I take this to mean that the oil’s viscosity damps the second-order resonance created between the rotating mass of the platter and the compliance of the belt/string acting as a spring in this rotating mechanical system. If that second-order resonant system has an under-damped peak it would “amplify” motor noise as well as any rotational noise from the spindle bearing itself. I have to assume that Micro knew what it was doing here, and that the benefits of some degree of viscosity are real.

Well, you have tried replacing the oil and I have not. Playing with various oils and additives is not as easy as rolling tubes or capacitors, is it? Smile I’m less inclined to touch mine now that I have given this more thought. Besides I have other fish to fry, including our 5000 power supply project!

Does your second 5000 still have its original oil, for comparisons?

Romy, you would probably say that this is all very interesting, but that the heavy platter and plinth render much of this discussion as academic. You might be right.


______________
Brian
10-31-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017

Post #: 95
Post ID: 24533
Reply to: 24532
Lubing
 Romy the Cat wrote:

Find another hobby them as to cultivate the Micro fetish is not healthy things to do. A TT is just a tool for getting something ease. If you willing to dedicated your to cultivating tools then it is up to you but be advised that Micro did not bold good tonearms and cartridges.


Romy, You can call as you want but to spin vinyls nowadays is not just about sound...
I'm not really thinking in Micro tonearm not at all in their cartridges but SME 3012R, flagship of Fidelity Research, SAEC, Audiocraft, Exclusive is on my scope.
Some advice for vintage cartridges, momo as well I really welcome.

 Romy the Cat wrote:
Do you have a Cat in home?


I have a cat but do not an air bearing Micro :-)


To change few electrolytic caps is not a big deal and I'm curious about your future power supply upgrades.
I agree with Wellinington, the bearing question is more complicated.
Maybe there is reason that Micro used PB in their oil or just as a good anti-wear additive was common for lubing in that period. Now we cannot find easily such compounds so to replace the oil with original parameters is impossible.
Compare to old one there are many modern oils but also dozen of forum topics where people are argue about what is good or not.
I got an idea! One of my friend who is the CEO of the biggest petrol company in CEE for sure can help me to do some investigation.
I'll took the oil out from one of my RX-5000 and I send to laboratory.
We will know for sure the index of viscosity and much more data. No doubt the 30 year old oil is full with oxidants, moisture and wear contaminated incongruous materials.
Really I don't know which is good, not to touch the Micro and keep the bearing in such glop or try to find a new lub for the engine refreshment and conservation?
10-31-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 96
Post ID: 24534
Reply to: 24533
Meanwhile back in Kansas
Hi Wellington,
I have rebuilt the other table after living with both for several months of comparison. The oil comparisons were done over several months as well, granted the differences in oil viscosity well smaller compared to the other changes. The main differences was that speed stability was improved over the stock bearing, and turntable came up to speed much sooner. Some of the speed problem was also due to dried out electrolytic's. The biggest improvement came with the stainless steel platter(heavier) and copper mat.
Hi Measet,
Basically the modification to the power supply would be
a) Outboard DC supply with a toroidial  transformer , filtering and pre-regulator.
b) Second regulator inside the motor unit.
c) Possible tuning of the servo circuit driving the motor.

The bearing rebuild is not really that hard and I have rebuilt three RX-5000 bearings and four RX-1500 bearings.
Note. The RX-1500 Air uses grease for bearing lube because because regular oil would clog up the air passage.
Nice looking cat, by the way.
10-31-2017 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,049
Joined on 05-28-2004

Post #: 97
Post ID: 24535
Reply to: 24533
Do not ask me to prove it.
 measet wrote:
I'm not really thinking in Micro tonearm not at all in their cartridges but SME 3012R, flagship of Fidelity Research, SAEC, Audiocraft, Exclusive is on my scope. 
Some advice for vintage cartridges, momo as well I really welcome. 

I am not good to give advice. I personally love SME 3012R and after having a few other tonearms I wish I had all 3 of my tonearms SME 3012R. Does it means that I need to advice it? To me audio is very individualistic discipline.  It is like a type underwear that you ware. You do not want to copy anybody and you do not care if anybody copies you or follow your recommendations. It is about to find a proper underwear to what you feel… The same goes to advice about the mono cartridges. I for instance had 3 SPU Mono identical cartridges. One was beyond believe wonderful, truly stunning. My cleaning lady killed and two others identical cartridges that I got as a replacement are not so good, in fact they are very bad, including the one that I run on my Mono arm now. So, what can I recommend? I have no idea….
 measet wrote:
I agree with Wellinington, the bearing question is more complicated. 
Maybe there is reason that Micro used PB in their oil or just as a good anti-wear additive was common for lubing in that period. Now we cannot find easily such compounds so to replace the oil with original parameters is impossible. 
Compare to old one there are many modern oils but also dozen of forum topics where people are argue about what is good or not. 
I got an idea! One of my friend who is the CEO of the biggest petrol company in CEE for sure can help me to do some investigation. 
I'll took the oil out from one of my RX-5000 and I send to laboratory. 
We will know for sure the index of viscosity and much more data. No doubt the 30 year old oil is full with oxidants, moisture and wear contaminated incongruous materials. 
Really I don't know which is good, not to touch the Micro and keep the bearing in such glop or try to find a new lub for the engine refreshment and conservation? 

I feel different. I think that bearing question is not complicated and particularly the Micro original intend is not relevant. Over the 40 years since Micro was made there is a HUGE progress in lubrication, enormous, and the oils that we have today are much better then whatever Micro was able to see in the dreams. I am sure the same as the bearing material. Micro used steal for the bottom ball plate in RX5000 and I have seen a few of them that had very bad indentations. Today we would probably go with different materials, perhaps china, which would require very different lubrication. Years back, I had a theory that the RX5000 with steal ball and steal slightly worn up bottom plate, where the ball is sitting in very-very shallow hole is “better for sound”. Do not let me to prove it, I can’t.


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-06-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017

Post #: 98
Post ID: 24548
Reply to: 24535
Intervention is needed
Just take a look what I found after dismounting the bearing and motor. No question, the intervention is needed.
I have already replaced all the caps and two trimmers, I removed the rust from the ferrit and magnet after that I lubricated slightly the bearing of motor.
ry-5500_motor.jpg

The ceramic ball is cracked so I'll replace it with Si3N4 one, the oil is very dark and small dusts are visible. I just drew a schematic about bearing.  I found enough lubricant in the bottom bath but the quantity was less than to be enough also for side part of the shaft. It is logical but somebody can confirm that the bearing must be filled full with oil. I'm courious if the thrust plate was drilled intentionally or has been eaten by ball, the hole it seems too deep for a wearing sign.
rx-5000_bearing.jpg

I found here very fine hydraulic oil with viscosity 46 but it looks quite thick comparing to the original.
Jam, please let me know what kind of oil do you use, maybe do you know also the index of viscosity of it. Regarding ss platter do you have the same design what Wellington invented or you just copied the parameters of gun metal platter?
Thanks a lot.
11-06-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017

Post #: 99
Post ID: 24549
Reply to: 24548
Rx-5000
Hi Measet,
The oil I would use is Zoomspout, it works great. I have a platter with a similar profile that Wellington has, my second RX-5000 has a stainless platter made by Micro Seiki with the same dimensions as the original gun metal platter.
Just flip the thrust plate over and use the side without the dimple, do not try to use a different material for the thrust plate (eg. Carbide) as it will start to wear pretty soon. Your motor looks in great shape,  the rotor can be protected with on a light coat of lacquer. I would replace the O-ring seal on the bottom of thge bearing.
You can get hold of me at jsomasundram@hotmail.com if you need any further help.
Jam
11-06-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011

Post #: 100
Post ID: 24550
Reply to: 24549
Nice photos
Excellent photographs, Measet. There is not a lot of documention about the inner workings of the 5000 and this helps.


______________
Brian
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   Target    Threads for related reading   Most recent post in related threads   Forum  Replies   Views   Started 
  »  New  The Foolishness of Analog People..  Late to the discussion but cannot resist...  Analog Playback Forum     56  559970  01-30-2006
  »  New  Micro RX 5000..  Alternative method...  Analog Playback Forum     9  66188  11-09-2008
  »  New  Micro RX5000: is that bearing spins normally?..  How many turns do the good bearing......  Analog Playback Forum     7  39820  02-03-2014
  »  New  Fetish of Micro's?..  Size of ceramic ball...  Analog Playback Forum     122  370104  10-29-2017
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