It depends on the table, actually on the bearing to be more precise. What works in one bearing could be a disaster in another.
If your bearing was designed to use grease, then grease is what you should use. Bearings designed for grease typically have large tolerances between surfaces. Using a much thinner, lighter lubricant like machine oil will allow play, which will increase surface wear and shorten component life.
OTOH, a bearing designed for lighter grade oils would have very tight tolerances. Packing that with grease, if possible at all, would make the bearing virtually immobile.
Stick to what the TT manufacturer recommends.
I agree with Dougdeacon on what the maufacturer recommends. I run a Michell Gyrodec and I use Mobile 1 5w30 Synthetic motor oil on my bearing.
Dear friends: Dewald visser is the manufacturer!!!!
Regards and enjoy the music.
In that case he should know the answer!
It depends, as I said, on the tolerances of the bearing and also on the materials inside the bearing.
With that information a mechanical engineer with lubrications expertise could make a recommendation based on real knowledge. Recommendations from audiophiles who use different tables would be useless, and I've already posted many useless things here! ;-)
Being a mechanical engineer, I can tell you that it is fairly straigh forward to pull out a machine design text and look for lubrication weight formulas. It's all based on hydrostatic forces created by the oil between two rotation cylindrical surfaces.
The tough part is determining the clearance between the two bearing surfaces. I seriously doubt you find such informoation in the turntable manual.
Long story short, its just like Dougdeacon said- large clearances need grease (often called bushings) and small clearances need oil (often called journal bearings).
I have sound, after careful research that oil is the better choice for lubing the bearing...
It is a low tolerance bearing with plastic sleeves and thus the oil be better.
Thanx anyway - what I want to know is what do you find works best in your machine?
On my rega planar 3 I replaced the stock (80w hypoid gear oil) with 140w Mobil synthetic gear oil (SHC 634) and the sound improved very noticeably.
I think Lucas has the best answer, but it is worth experimenting with viscosity, as a more viscous oil can better damp the bearing, and reduce rocking.
I have an oracle alexandria with a worn upper bearing. Not sure what oracle reccomends, but they told me to run something heavier. I am running the silicone type stuff that is meant for the well tempered tables with great success, the sound quality was very dramatically improved. It is VERY thick and a pain to clean up. It got rid of almost all of the sibilance I was experiencing.
If you have an oracle, the upper bushing/bearing is likely worn.
Just thought I would chime in with some experience I had last week.
Doug's and Raul's answers are the most comprehensive.
Proper lubrication (e.g. protecting the bearing) is the starting point.
From there, you need to try various lubes to determine what sounds the best. By changing viscosities, you are tuning (or de-tuning) a resonant system which is comprised of all of the rotating parts in your turntable:
- Motor and its torque
- Controller circuit - how quickly it responds to the changing environment.
- Drive interface and its compliance (e.g. belt / material, idler wheel / material, direct-drive)
- Platter mass
- Bearing tolerance
Changing any one of these will affect what you hear (especially as far as timing is concerned), and not necessarily for the better.
Let your ears tell you what's right, and realize that if you make a system change elsewhere, that you may well need to return to this evaluation.
Thom @ Galibier
Thom - thank you for the feedback.
I think I have found the lube for my machine - the sound is open & relaxed with lots of "air" in between. Rumble has gone down to virtually zero and it was a change for the better.
You see - I use radical VESCONITE to make the main-bearing sleeves from. This is a super low-friction plasic with excellent wear-resistance. It doesn't have that nasty ring/ping that copper have... I like it very much.
I have found that the lubricant that I use in my trumpet to be good and musical to boot.
FWIW, changing to Mr. van den Hul's zirconium oxide-doped spindle oil made all the difference in my Goldmund TT.
Supposedly the super hard zirconium oxide particles act like nano ball bearings which actually keep the metal surfaces apart from one an other, thus eliminating bearing noise. The oil itself is used more as a "vehicle" to keep the particles in suspension.
Because the zirconium oxide is so hard, I'd check with A.J. vdHul before using it in bearings with plastic components.
Have you compared this lube against something of equivalent viscosity without the particles?
I'm trying to separate the relevant variables in the context of your turntable.
Thom @ Galibier
Thom, I've had this TT since new (it's a Studietto w/ the JVC quartz controlled motor) and only changed the oil twice before in the last 16 years (my bad!) although it hadn't dried out or anything. (I think I used some kind of super-refined machine oil but I can't remember for sure now -- could have been 10-40W ;--)
About two years ago, I decided to un-spring the TT and replace them with sorbothane PandaFeet in densities corresponding to the different spring strengths. This not only made the table a lot easier to use, but resulted in tighter bass and a really black resonant-noise-free background.
So when I read about the vdH spindle oil on their website, I thought it sounded pretty interesting in theory, plus a vdH dealer in Belgium said he got great results on his Pluto TT. To be honest, I was NOT unhappy with my TT's performance at that point, but being an audiophile, well you know the rest. . . .
Anyway, I put some in my TT and a friend's Studietto, and we both noticed the same two improvements -- they were subtle, but the kind of subtle that if you had to go back, you'd be unhappy ;--)
The JVC rotor/bearing has a hemispherical shaft bottom that rides on a (looks like) teflon or nylon pad, I'm not sure. And it only takes about 1.5 cc for a complete lube replacement, so I have quite a bit left if you'd like to try a little ;--)
It's funny that Oracle recommended a heavier weight oil for the old, worn bearing of your alexandria. They told me that the teflon coated bearing in the Delphis would probably benefit from lighter oil in an older bearing due to the fact that the teflon swells slightly with age, tightening up the clearance.
I don't know what type of bearing is used in the alexandria. Do you know? Is it teflon coated? From what they told you, it seems as though it is not teflon coated.
To see whether you have too heavy of an oil in your bearing, give it a little spin and observe how the platter comes to a stop. If it's quick and you can clearly see the point when it stops, either the clearance may be too tight or you might be using too heavy of an oil. In this case you can use a lighter oil. It should come to a stop very slowly. It should be difficult to see when it actually stops.
Dewald_visser, what did you machine the bearing clearance to when you built your table?
Lets just say the VESCONITE sleeves fits precisely over the platter shaft. The engineer did a fantastic job of making it fit perfectly without any 'resistance'.
You see, Vesconite has a build-in lubricant and can be used without oil... but oil is needed to quiet the main-bearing.
The shaft is 20mm and the tip rides on two ball-bearings ontop of eachother.