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Turntable bearing oil? Modern synthetic or traditional

maccavelli

pfm Member
I do a lot of cycling, and a lot of listening. I remember, a long time ago, a fellow audio enthusiast (and keen cyclist) and waxed lyrical about how effective gun oil was on his chain. I'm from a dry lube synthetic age and will use teflon fortified chain lube on my Madone road bike. But it did make me wonder, how good is the bearing oil they use for the bearing housings in turntables?

I can understand thinner, synthetic lubes are probably not suitable for heavier mass, conventional thinking designs such as an LP12. But I reckon it's probably worth tinkering with a few different lubricant samples.

I'm sure my LP12 inner platter spins freer with some of my modern chain lube.
 
Many decks use sintered bronze bushings and some modern oils are not safe to use in this context (they'll damage the bronze), so I'd want to be sure of the specific bearing structure before wandering too far from the manufacturer's recommendation. I'm sure the same issue exists with some plastic bearing inserts too, e.g. very early TD-124s, one generation of LP12 etc.
 
I thought bearing oil was EP80 or 90, EP stands for Extreme Pressure like the point load between the turntable shaft and ball, so thin oil might be good enough to maintain a film of lubricant between the ball and shaft and you might as well run it dry.

Pete
 
Man,

I just don't know where to go with this. I'll try to be simple about it and say that there is a certain lube for every application for the reasons mentioned above and even more. Applies to other products as well. Specific products for specific reasons, I say. To muddy things a little, there will always be a new and improved(not proven) product on the market, tempting us along the way.
 
My TT runs dry that is no oil.Oh and no springs nor grommets nor any bodge like the screw etc...

LP12 is really old technology especially considering its price.

Cheers,

DV
 
most of the TTs are perfectly fine with sewing machine oil unless supplied with something entirely different.
at least that's what i use. despite all the internet hype and warnings. never had any problems with at least 4-5 decks i used, idlers or kuzma.
 
Your lp12 will spin freely with light oil but that might not give the greatest speed stabilty. Also more viscous oils provide more physical damping of the bearing. I still consider the Lp12 bearing to be very advanced, they have a long lifespan and very low self noise and have a hybrid construction. Apart from those with ceramic shafts I'd struggle to think of many more advanced.
 
... I'm sure my LP12 inner platter spins freer with some of my modern chain lube.

Be carful with chain bicycle lube. As a cyclist myself (both road and general commuting) most chain lubes are actually a thick synthetic lubricant (usually a paraffin or Teflon based substance) dissolved in an evaporative fluid for easy flowing application.

Once applied, the chains lube’s evaporative fluid is intended to evaporate off the chain leaving behind an even coating of the lubricating agent.

On older Linn bearings that have accumulated a few decades of use, a 50-weight hypoidal gear oil with an EP (extreme pressure additive) is usually a good start.

LPSpinner
 
On the Linn bearing you can use pretty much anything you like as long as it isn't in a volatile carrier than makes the plastic swell.
 
If your turntable uses sintered bronze bushes it is important to use the correct type of lubricant.

Sintered bronze bushes are porous and can be made to absorb oil. This gives them a certain degree of self lubricating ability.

Older automotive gear oils are most definitely a very bad choice as they contain sulphur based EP additives (extreme pressure) which are corrosive to yellow metals. Most modern gear oils contain buffered or deactivated sulphur which is less far less corrosive to yellow metals. However these are still damaging to yellow metals when you have a hard metal like steel in contact with a soft metal like bronze. This is exactly what we have in a turntable such as a Thorens TD124 or TD125.

You might get away with a modern gear oil I wouldn't risk it.

Engines oils are a slightly better option but they do still contain additives which are totally irrelevant in a turntable bearing and may even cause some problems.

I would not use any oils containing PTFE (teflon) or molybdenum disulphide.

The best easily available type of oil to use is an oil designed for air compressors. These oils do not contain additives which will be damaging to bronze bearing, they come in suitable viscosities and they are relatively easily obtainable.

The main advantage of synthetic base stock oils is their ability to withstand higher temperatures without breaking down and there better cold flow properties at the other end of the temperature range. This is of no benefit in your turntable bearing. Having said that the cost difference is pretty negligible in the quantities we are talking about so if you want to buy synthetic then go ahead. It certainly won't do any harm and it may provide some slight advantages.

Compressor oils tend to come is ISO viscosity ratings. Here is a rough guide.
ISO 32 = SAE 10
ISO 46 = SAE 20
ISO 68 = SAE 20w
ISO 100 = SAE 30

If your turntable has tighter bearing clearances a lower viscosity may be better and conversely if your turntable bearing is old and has widened clearances and higher viscosity may be better.
 
If your turntable uses sintered bronze bushes it is important to use the correct type of lubricant.

Sintered bronze bushes are porous and can be made to absorb oil. This gives them a certain degree of self lubricating ability.

Older automotive gear oils are most definitely a very bad choice as they contain sulphur based EP additives (extreme pressure) which are corrosive to yellow metals. Most modern gear oils contain buffered or deactivated sulphur which is less far less corrosive to yellow metals. However these are still damaging to yellow metals when you have a hard metal like steel in contact with a soft metal like bronze. This is exactly what we have in a turntable such as a Thorens TD124 or TD125.

You might get away with a modern gear oil I wouldn't risk it.

Engines oils are a slightly better option but they do still contain additives which are totally irrelevant in a turntable bearing and may even cause some problems.

I would not use any oils containing PTFE (teflon) or molybdenum disulphide.

The best easily available type of oil to use is an oil designed for air compressors. These oils do not contain additives which will be damaging to bronze bearing, they come in suitable viscosities and they are relatively easily obtainable.

The main advantage of synthetic base stock oils is their ability to withstand higher temperatures without breaking down and there better cold flow properties at the other end of the temperature range. This is of no benefit in your turntable bearing. Having said that the cost difference is pretty negligible in the quantities we are talking about so if you want to buy synthetic then go ahead. It certainly won't do any harm and it may provide some slight advantages.

Compressor oils tend to come is ISO viscosity ratings. Here is a rough guide.
ISO 32 = SAE 10
ISO 46 = SAE 20
ISO 68 = SAE 20w
ISO 100 = SAE 30

If your turntable has tighter bearing clearances a lower viscosity may be better and conversely if your turntable bearing is old and has widened clearances and higher viscosity may be better.


Some good advice there and also in the posts above some misunderstandings confusing perhaps oil viscosities and shear resistance.

Avoid anything with sulphurs in it such as gear oils, as these will corrode bronze bushings. Modern engines oils ARE generally safe for spindle-end ball bearings providing you pick one without any sulphur additives, Teflon or Moly'. Viscosity is not the same as shear strength, and you CAN use higher viscosity oils with tighter tolerances, just as you can use low viscosity oils with very high shear resistance. A motor oil such as a synthetic SAE 5W30 is fine for most turntable ball bearings and spindleshafts and should not damage sintered bronze bushings. There are many sintered bearings used in the automotive industry running on this oil.

If in doubt, 3-in-1 is commonly used by the machine shops locally to me as sintered bearing oil (I asked).
 
Just for the record (no pun intended) I use an ISO 46 fully synthetic compressor oil in my own turntable.
 
I use 10k silicon diff fluid.

I was once told by a reliable (aerospace enginer) friend that Silicone (please note spelling SQ: Silicon is a metallic element) fluids do not have particularly good shear strength, even if high/thick viscocity and, hence, would not be suitable for highly loaded metal-to-metal bearing surfaces, such as gear cogs, ball thrust bearing etc.

Silicone fluid is suitable for metal-to-plastic bearings and pads, such as Well Tempered platter bearing etc.
 
just to resurrect this thread,my rock 2 has an inverted bearing,after reading a thread elsewhere and a suggestion from mark i tried some 30.cs silicone fluid/oil.
to my ears it seemed to reduce the noise floor,i heard a noticeable difference,tonight i tried 12,500 cs and that's better still.
so whats going on? i can only assume the heavy viscous fluid is damping out micro vibrations?
my only slight concern is its lubrication properties compared to oil.
 
I still need to try high viscosity diff oil in my LP12 - it certainly makes a difference RC car drive trains :)
 


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