| Search | Login/Register
   Home » Analog Playback» Copper Mat on a Micro Seiki Gun Metal Platter (123 posts, 7 pages)
  Print Thread | 1st Post |  
Page 6 of 7 (123 items) Select Pages:  « First ... « 3 4 5 6 7 »
   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  584727  01-30-2006
  »  New  Micro RX 5000..  Alternative method...  Analog Playback Forum     9  69850  11-09-2008
  »  New  Micro RX5000: is that bearing spins normally?..  How many turns do the good bearing......  Analog Playback Forum     7  42842  02-03-2014
  »  New  Fetish of Micro's?..  Size of ceramic ball...  Analog Playback Forum     122  413907  10-29-2017
11-07-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 101
Post ID: 24551
Reply to: 24550
Silicon nitride
I think that I saw someone offering a silicon nitride thrust plate along with the ball bearing years ago. Jam, your solution of simply flipping the thrust plate upside down makes perfect sense, but I suppose a silicon nitride (or similarly hard) plate might offer the lowest friction/wear and lowest noise solution. The dimple in Measet’s plate looks cavernous, almost enough to have gradually affected VTA Smile But I suppose the close-up picture makes it look worse than it is.

That cracked ball bearing is a reminder to us all that brittle ceramic balls, while hard, can’t handle very much shock. This reinforces the importance of VERY GENTLY lowering the platter down onto the spindle using the T-handles. And never try to move the turntable with the platter in place (who would try with that much weight?) Measet, I am not suggesting that you were less than gentle with your platter, but that over the decades and through multiple owners, who knows what that ball had been subjected to? Jam, were either of your original ball bearings cracked? A ball on a fresh thrust plate makes contact on an infinitesimally small point, therefore pressure (which is force divided by area) is enormous at that point. Fortunately silicon nitride is more shock resistant than other ceramics. I have a silicon nitride ball ready if I decide to perform bearing surgery, but so far I have resisted the temptation to open it.

By the way, I put a tiny amount of grease onto the conical spindle surface that mates with the platter. Not enough to ooze out, barely more than a greasy fingerprint. I do this to make it easier to pull the platter the next time.

______________
Brian
11-07-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017
Post #: 102
Post ID: 24552
Reply to: 24551
Old oil to laboratory
Jam, Thanks for great infos.
I suppose the original MS ss platter is lighter than the gun metal one? Are you filled with oil the whole bearing or just the bath in the bottom side? The viscosity of oil would be ISO 32 VG as my new oil which is 46 VG looks thicker a bit than the original one. Just for fun I sent out the old oil to laboratory and we will see the main properties of it. I have no doubt the test result will show us many contaminations (just think on the Fe what disappeared from the plate) which doesn't help to the lubrication, even can cause damage.
Please find a closer pic of dimple, looks strange:
thrust_plate.jpg

To flipping the plate is a good idea but if we are thinking in long-term can be worth considering the idea of silicon nitride or other hard plate.
11-07-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 103
Post ID: 24553
Reply to: 24552
Scratchy balls
Measet, Because your ball bearing was cracked, it might have locked into one position relative to the spindle and then the sharp edges of the crack wore those concentric scratch marks into the thrust plate. Just guessing here.

I look forward to reading the lab results regarding the oil.

______________
Brian
11-07-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 104
Post ID: 24554
Reply to: 24553
Bearing issues.
Hi Measet,
The original platter for the RX-5000 was gun metal which I replaced with a platter with a similar platter to Wellington's weighing about 50 lbs. ,  the other table came from Japan with a original stainless platter made by Micro Seiki (rare). The density of gun metal and steel are about the same. The main differences here are the resonant properties of the material used and total mass of the platter. I have found that Stainless steel sounds the best, followed by gun metal and aluminium being a distant third. I will post pictures of my platter if you wish.
The bearing has to be filled completely with oil. After you have cleaned the bearing and replaced any parts that have aged, insert the spindle into the bearing until it clears the bottom bushing and fill with oil from the top wile pushing the spindle up. When the area between the bushings is filled and the spindle is all the way up invert the bearing and fill the bottom with oil. Replace the bearing and thrust plate and screw the plate back to the bottom of the bearing, you will fell some resistance due to trapped air, this is taken care by holding the bearing horizontally with the setscrew in the middle of t facing up. Slowly release the setscrew to release any trapped air and re-tighten the set screw. Clean any spill with alcohol. 
Your thrust plate was damaged by the defective ball. Newer ceramic materials are a lot tougher. There will always be a small dimple on the thrust plate which is normal. 
I would advise always using a stainless thrust plate as harder materials such as ceramics and carbide will sometimes start breaking at the interface between the ball and thrust plate. Steel being a different slightly softer material prevents this. I have confirmed this with several carbide thrust plates I have tried. An all ceramic bearing might work with a light platter but no so with a Micro Seiki with a heavy platter.
About the question of oil viscosity, I prefer a lighter viscosity than originally used and due to faster startup and speed consistency, I feel you do not need lead or other questionable additives with today's synthetics.
I would like to know if hear any differences with the repaired bearing and if there are any changes in start up speed.
Jam
11-12-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017
Post #: 105
Post ID: 24555
Reply to: 24554
Lab result
Hello Guys,
Here is the lab result, is in Hungarian but all data it speaks for itself. It is mentioned that the oil contains Pb as main anti-wear additive what MOL company doesn't apply from 20 years. The kinematic viscosity  is 37 mm2/s, so it can bi fit to ISO VG 32-46 standards. It is contaminated heavily by few elements and the wear pollution is very critical (see in red Cu, Fe and Mn). Of course I described all background info to lab engineer (very kind and willing lady) and she pointed me out that condition of this lubricant is very harmful to the bearing system and the immediate replacement is needed. She advice me an oil for cleaning (MOL Hydro HLPD 46 AL KM) and another extra fine one for final use (MOL Hydro 46 Al Extra) which has perfect anti-wear properties also in case of low rpm. Both oil looks quite thick but as I got small bottles I did a try. The turntable runs smooth but has got the stable speed later then before and even later when I mounted the thread. I do not have any arm installed now so I coudn't make audition. My oppinion is the same like Jam has, better to use a bit thinner oil, maybe ISO VG 32 would be perfect. If you would like more info just let me know, if needed also I can forward further questions to the lab.
mol_lubricant_forum.jpg
11-12-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 106
Post ID: 24556
Reply to: 24555
Valuable data!
Measet,

Thank you very much for posting this extremely valuable information! It adds to the data base for the 5000. I will have to translate it to English using the Google translator. Now, if someone could locate and post the RY-5500 schematic, we’d all be even more pleased!

A lot of that iron contamination and maybe some of the other contaminants must have come from that worn divot in the thrust plate. That lost material had to go somewhere, and it went into the oil as a suspension.

You say “better to use thinner oil” after noticing that your platter takes longer to come up to speed. Part of that change is viscosity and part of it must be that you have filled the housing to full capacity now.

But why is it “better to use thinner oil”? I would say don’t worry about the viscosity as long as you are matching whatever MS used. I think I posted earlier some words directly from Micro Seiki itself about the oil’s viscosity providing a valuable damping function of rotational resonances. This is not my opinion; it is their design intent, and it makes sense. I know that my friend Jam disagrees and used lighter oil, but I think I will choose to stay with the original intent.

Garrard 301 aficionados (I am not one) argue about the advantages of the grease bearing version versus the oil bearing version. Perhaps a similar argument here.

______________
Brian
11-12-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017
Post #: 107
Post ID: 24557
Reply to: 24556
Translation
 Wellington wrote:
I will have to translate it to English using the Google translator.
Wellington, if you would like I can revise your translation.
 Wellington wrote:
But why is it “better to use thinner oil”? 
Of course this is just my opinion.  I don't know exactly how the bearing was filled, probably was not full with oil but what I know with new VG 46 oil my tt get the right speed later compared with the old one and also compared with my untouched RX-5000. For sure we cannot obtain new oil with VG 37, as the standards are 5, 10, 15, 22, 32, 46, 68, etc... Also we can consider that the viscosity of original oil was 32 mm2/s and since 40 year it could changed a bit thanks to wearing, oxidation, contamination, etc. and reached the current 37 mm2/s. I do risk nothing to try also the ISO VG 32 oil to see what is the difference. I think VG 32 is also a thick oil, good enough for damping. Of course the verdict would be after auditions.
11-12-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 108
Post ID: 24558
Reply to: 24557
Oil
You are right that 32 is not too far from 37, but I would probably not want to use any lighter oil than 32. Yes, a translation of the Hungarian report to English would be appreciated! No rush.

______________
Brian
11-13-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 109
Post ID: 24559
Reply to: 24558
Much to do about oil.
The oil I use has a viscosity of about 30-31 and I have used it for years with no problems. I have tried about six different viscosity oils and grease and the best results were with in the range I specified for (sound as well as mechanically), please feel free to experiment. I have done these experiments both with the RX-1500 and RX-5000. I also find using a lower viscosity oil helps adjusting belt tension easier.Modern synthetics are much better than lubricants were forty years ago. I remember when we used dolphin based oil in tape decks because there were no alternatives. Micro used the best compromise they had at the time..........but then you don't have to take my word for it.  
11-13-2017 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 110
Post ID: 24560
Reply to: 24559
Oiled up
Jam, when you first mentioned ZoomSpark perhaps your spellchecker was hyper-active and you meant Zoom Spout. I think it’s this product, right?

http://www.highsidechem.com/zoom_spout.html

OK, so that is ISO 32 (at the bottom of this page) paraffin oil, not too far from the ISO 37 measured by the lab. When you consider that the oil tested probably had gummed up somewhat after 30 years, plus had lead particles added, it might have been right around 32 anyway when it was new. I think we’ve converged.

I admire your willingness to test and experiment here. Changing oil in a Micro Seiki bearing is not quite as easy as changing interconnects or rolling tubes 😀 If and when I do mine I would like it to be the only oil change I ever have to do, and this discussion and your experience have helped enormously to understand what’s needed.

______________
Brian
11-13-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 111
Post ID: 24561
Reply to: 24560
Sorry my apologies.
You are correct. It is Zoom Spout. There are several oils used for turbines that work well.
Once you have done a few it gets easier....still messy though. If you are willing to do it. I will send you the necessary supplies.
11-13-2017 Post does not mapped to Knowledge Tree
measet
Posts 15
Joined on 08-15-2017
Post #: 112
Post ID: 24562
Reply to: 24561
HS-80 still is on the table
Hello Jam, 
Have you experience also with HS-80? After I found how the Micro's bearing is behaving with thicker oil I have a feeling that my flywheel has no right or fitting lubrication and therefore I'm not able to setup with neither RX-5000. I didn't dismounted yet but probably I will do it. Has similar design like the tt bearing but I wonder if Micro used the same oil in HS-80?! By my logic no, as the working speed is higher and the turning resistance is smaller. What do you think?
11-14-2017 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 113
Post ID: 24563
Reply to: 24562
HS-80
Hi Measet,
I tried the HS-80 and it worked best with the bearing lubricated with lower viscosity oil (same as I used in the RX-5000) and kevlar string but once set up (which can be a pain) I could not hear much difference. Belt tension made far more difference in sound. 
Granted the above experiment was tried with a stainless platter and not the gun metal platter.
The bearing is smaller but similar. Cleaning and lubing the bearing can make a difference on ease of setup but ...........I chose to buy a second RX-5000 instead.
You might get different results. Please let us know.
11-30-2022 Post does not mapped to Knowledge Tree
rom661
Kansas City
Posts 10
Joined on 04-03-2022
Post #: 114
Post ID: 27028
Reply to: 24501
CU-180 and bearing maintenance
I've had an RX-5000 for a few months now.  I've read yours and other comments with great interest.  I'm a long time high end dealer who is losing his vision and is mostly retired.  I've known this particular turntable for about 35 years since it belonged to someone who was a friend, my lawyer, and a customer.  It hadn't been played in 20 years but the bearing moved freely.  I don't want to bore you overly much with details but I spent a month or so restoring its appearance, changed out the Grado tonearm to a Dynavector 507 MKII with a Dynavector DV1-S cartridge and found a truly flat CU-180 copper mat, which lived up to your description.  I write this because of your account of rebuilding your bearing.  This guy is functional but I believe there is too much friction.  Romy's 33rpm then disconnect belt and it should spin for 3 min. only goes for 30 seconds.  I'm at a total loss as to how to approach the bearing.  It may be that lubrication is all it needs.  Obviously there's no agreed upon answer to that, even for viscosity.  Mike Pranka, a friend who distributes Dynavector is a car enthusiast and has several viscosities of extremely high quality gear oil.  I've no idea how to address the bearing itself.  Apparently the thrust pad can be flipped so maybe that would do it.  Any pointers, either tips or literal pointers to "how to"information?  Thanks for your time and the CU-180 tip.  I had tried a half dozen options and it was like the Goldilocks story, just right.  Damped but not dead, focused but still lively.

Richard Milam
12-01-2022 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 115
Post ID: 27029
Reply to: 27028
Bearing fix
Richard,
My platter spins for about 8 min. I would replace the oil with a light turbine oil and replace the rubber o rings as well.Replace the ceramic ball with a high tolerance silicon nitride piece and flip the thrust plate and all should be well
Regards,
Jam 
12-01-2022 Post does not mapped to Knowledge Tree
rom661
Kansas City
Posts 10
Joined on 04-03-2022
Post #: 116
Post ID: 27030
Reply to: 27029
Thanks
Thanks so much for the reply.  Not to push your courtesy further, but are these readily available components?  Lube is no problem, of course. Thanks again.

Richard Milam
12-01-2022 Post does not mapped to Knowledge Tree
rom661
Kansas City
Posts 10
Joined on 04-03-2022
Post #: 117
Post ID: 27033
Reply to: 27030
Is RX-5000 bearing assembly the same as RX-1500?
Not much to say since I asked the question in the Subject line.  If anyone knows, please answer.  Thanks

Richard Milam
12-02-2022 Post does not mapped to Knowledge Tree
Wellington


South Florida
Posts 38
Joined on 10-03-2011
Post #: 118
Post ID: 27034
Reply to: 27033
Bearing sizes
I have owned both. I still have the 5000, but recently sold the 1500. As I recall, the bearing for the 5000 is considerably larger and heavier than the bearing for the 1500.

______________
Brian
12-08-2022 Post does not mapped to Knowledge Tree
rom661
Kansas City
Posts 10
Joined on 04-03-2022
Post #: 119
Post ID: 27039
Reply to: 27029
Source for replacement ball
Thanks again for all the info, Jan.  I picked up some Mobil DTE 25 hydraulic oil at the recommendation of someone else.  Do you feel that is inappropriate?  You seem to be the resident expert on this.  I'm going to flip the plate but as long as I'm there I would like to have a replacement bearing ball if it seems needed.  I've no idea where or specifically what to look for.  Any suggestions would, as always, be appreciated.

Richard Milam
12-08-2022 Post does not mapped to Knowledge Tree
jam
Auburn
Posts 21
Joined on 10-10-2017
Post #: 120
Post ID: 27040
Reply to: 27039
Oil and Ball
I would use a trurbine oil like Zoom Spout and get the bearings from Boca Bearings

https://www.amazon.com/Original-All-Purpose-Turbine-Telescoping-Spout-GuruShop/dp/B09MDJPKV5

 https://www.bocabearings.com/products/bearing-and-ball-types/balls/ceramic-silicon-nitride-(si3n4)-series?loadseries=true&ProductType=0

Jam
Page 6 of 7 (123 items) Select Pages:  « First ... « 3 4 5 6 7 »
   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  584727  01-30-2006
  »  New  Micro RX 5000..  Alternative method...  Analog Playback Forum     9  69850  11-09-2008
  »  New  Micro RX5000: is that bearing spins normally?..  How many turns do the good bearing......  Analog Playback Forum     7  42842  02-03-2014
  »  New  Fetish of Micro's?..  Size of ceramic ball...  Analog Playback Forum     122  413907  10-29-2017
Home Page  |  Last 24Hours  | Search  |  SiteMap  | Questions or Problems | Copyright Note
The content of all messages within the Forums Copyright © by authors of the posts