Molybdenum based grease - please don't use!

[emgcr]

I too am no expert on the finer points of the chemical make-up of greases but attach the specification of the properties of the Comma CV Lith-Moly product which I like and continue to use successfully---"High in extreme pressure additives to give long life under heavy loads". I am also happy with the thought and concept of the equivalent of micro ball bearings in compression helping to avoid direct metallic contact in extremis. A grease capable of resisting a four ball weld load of 3,600 Newtons or 809 lbs or 7.2 cwt would seem to be a more than appropriate product.

[De Soto Frank]

Be careful about lubricants containing Extreme Pressure additives: these are usually NOT compatible with yellow metals, eg: brass / bronze.

EP lubes were developed for applications where there are a combination of extreme contact loads and sliding loads... a great example would be hypoid ring and pinion gears in an automotive differential. The loading in such an application is many times the forces that are generated in most spring-wound talking machines.

It would seem that some important characteristics for spring barrel grease would be:

1) slipperyness

2) corrosion protection

3) neutral pH

4) resistance to evaporation of volatile elements, causing drying / sticking.

5) Low odor factor


I wonder if the modern family of synthetic lubricants might have a suitable member ?


Folks in the Antique Fan Collectors Society are really keen on "Royal Purple" synthetics...

[need4art]

I have been working on and building vintage cars for 40 years and picked Mobil 1 Bearing grease after playing around with the Vaseline and flake combo and after using some other things that were recommended by the forum. I have used the Royal products as well but just like the "feel" of the Mobil 1.

The process I use is fairly simple. I remove the spring and clean it in my parts cleaner unit, with a bio safe cleaner. I use compressed air to dry it and then I look the spring over to see if anything is still adhered to it. I coat both sides of the spring with the Mobil 1 as I assemble so that the spring is coated once it is in the barrel. I add 1 tablespoon to the barrel once the spring is in place and then assemble.

I have used the Mobil 1 product on cars and my trailer and never had a bearing failure. Just to see whats going on I took the spring barrel out of my 5 year old victor IX and the spring and the Mobil 1 look like the day that I put it in and I play this machine almost every day.
Abe

[soundgen]

Wow ! what a lot of tosh ! In the UK HMV always lubricated with graphite grease presumably obtained from Victor or used a Victor formulae , this always fails sooner or later and leaves a solid yellow gunk behind which makes the springs bump and if not treated eventually break

I have replaced springs since 1975 , initially I used Castrol Graphited grease , when this became unavailable I used another graphited grease which worked well , when I couldn't get this again I used Moly grease all work well ,

In the UK Garrard and thus UK Columbia who's motors were made by Garrard just used grease , what type I don't know BUT it is almost never necessary to change the Garrard grease

So use any grease Graphited , Moly or ordinary BUT again as an old HMV guy who repaired machines at HMV told me , put loads in

[Ivor-Duncombe]

Please see article below.

[emgcr]

Many thanks for your further comments and in view of the fact that we now seem to have diametrically opposed opinions/experiences, it might be sensible to ask the manufacturers to comment with reference to our specific use ? In particular, it would be very enlightening to ascertain exactly why use of a Lith-Moly grease should lead to "bump".

[Ivor-Duncombe]

See below - I didn't see my posts and thought that they'd been lost again due to timeout. I was wrong in this regard.

[Ivor-Duncombe]

My preferred grease for lubrication of spring-driven motors and, indeed, automotive wheel bearings is Castrol LM. This grease is, as stated on the container as being:-

“A lithium-based NLGI No.2 multi-purpose grease with protection against rust and corrosion.”

 Suitable for use between –30 and +130 degrees Celsius.
 It is recommended for use in roller bearings such as wheel bearings and general purpose grease points.

I have also used Castrol LMX grease for servicing of larger motors (and whenever I have run out of LM grease for smaller motors). This grease is, as stated on the container as being:-

“A lithium-based NLGI No.2 complex high performance wheel bearing grease.”

 Multi-purpose grease with protection against rust and corrosion.
 A stable grease with excellent load carrying abilities and high temperature operating characteristics”

Both of these Castrol greases are a caramel light brown in colour and hardly translucent (i.e. light from a bright source only just passes through the grease when it is new). This is definitely not the same automotive grease as used back in the 1950s that looked like transparent golden brown petroleum jelly.

The molibdenum greases in my workshop (which I now retain for CV joint servicing only) are :-

1] Valvoline Special moly EP Grease: “Extreme pressure grease fortified with a fine molybdenum disulphide to render a superior grease for automotive and industrial lubrication.”

 “SUITABLE FOR CV JOINTS.
 Can be employed at operating temperature up to 170 degree Celsius.
 For use in trucks, tractors, draglines, bulldozers, cranes and many other off-road and industrial applications.

2] VW/Audi Original Schmiervett Fur Gleichlaufgelenke (MoS2) G000 602

3] Similar Spirex (brandname) CV joint lubricant

3]Similar Solid (brandname) CV joint lubricant

I have used (but not mixed) any of these molybdenum types for motor spring lubrication with most unsatisfactory results.

When restoring gramophone motors I replace or properly repair damaged, dented, worn or rusted spring drums when overhauling any motor. Springs are washed in solvent and dried out in the sun. I remove all traces of old grease and lightly polish spring surfaces which are dull or show signs of rust lightly with steel wool to remove light rust and clean them again with petrol when all surface rust was easily and satisfactorily removed. Pitted, cracked, kinked or previously repaired springs are discarded and replaced with new or good clean second hand springs. I found that reassembled spring drums only ever tended to bind and suddenly release (slither or bump) when I used molybdenum grease. Disassembly, removal of all grease, washing in solvent drying and reassembly with LM or LMX grease has resolved the problem in all cases of noticeable spring-binding or “bumping”.

I have standardised on lubricants mainly to stay compatible with the requirements of the workshop manual of my 1967 Jaguar. Initially, whenever I found that the specified lubricant for my Jag couldn't be found, I could always find a modern Castrol equivalent and so keep the car (and other Jaguar owners) happy. I have also use Castrol lubricants for my Honda motorcycles (of which I only own and use one at a time) I'm pretty sure that all well-known automotive lubricant manufacturers have suitable equivalents of one another's products, and I think that we will find that each of us is using one of three or four basic types of grease quite happily and successfully.

As far as I'm concerned, the modern lithium based wheel-bearing greases offer good resistance to rust, corrosion and wear that is far superior to the protection offered by the lubricants available at the time when my machines were made. I use any of my machines as often as I like and I have found that I can relax their servicing schedules considerably. I don't believe that Castrol oils and greases are superior in any way to other brands of lubricants designed to offer the same function and protection.

I inspect and service the motors only if they show signs of not operating properly, and otherwise at roughly 2-year intervals. Greases must not have moved away from interfacing surfaces that they are supposed to lubricate and the colour, "viscosity and smoothness" (gauged subjectively by feel and touch) of the lubricants should be good. Typically, if all goes well, I remove old lubricants and re-lubricate at 5 yearly intervals.

I have enjoyed and learnt something interesting from each of your contributions to this chat, thank you, and I hope that I have addressed any doubts or questions that you may have raised. I trust that you will find a suitable lubricant to replace molybdenum at the next convenient opportunity if you are using it.....but I feel that I have good reason to use it only for CV joints.

PS: Emger I believe that the reason I experienced spring binding in several machines, all with springs lubricated with one molybdenum-based CV joint grease or another is because CV joints don't have flat profile springs in them. The molydenum grease adheres extremely well to clean metal and does not cavitate (pull away from itself or from the metals that it is adhering to) and allow air in and release tightly bound spring coils. Most of all the CV joint grease specifications for all of its good properties are are well beyond those required of for light wheel bearing greases. For instance, if the viscosity CV joint grease would only ease up a little when the grease starts to work in a gramophone spring drum (perhaps thin out a little), then it would cavitate more easily. But you are quite right, we are not going to solve this between us. My motor springs bind if I use molybdenum and yours don't. It is possible that I wind my motor springs up a bit harder than you do (there are other variables too!). Please do investigate further and let me know what you find. I think that I've worked this one to death and everyone must be getting pretty bored by now. Regards, Owen.

[Orchorsol]

Interesting. Personally (and I have past experience of grease formulation, testing and manufacture - although not of these types) I can't imagine how cavitation, or the lack of it, could be significant. With the spring in mind, we are never dealing with the condition where two parallel surfaces are forced to separate in a perpendicular direction - there is always one open edge at the point of separation. So there can only be resistance due to very low viscosity of the grease, some kind of chemical binding (which I do not believe is possible between commercial moly grease formulations and steel), or some kind of mechanical resistance (nothing to do with the grease).

I'm with Graham and Ian, I believe moly CV joint grease is highly appropriate for the job.

[emgcr]

I have just spoken to the Technical Advisor (a trained chemist) from the company responsible for the manufacture of Comma grease and related our difficulties. He can think of no reason why their CV Lith-Moly product should lead to any problems of springs unwinding in an uneven manner inside a high pressure gramophone barrel situation. The pressures involved are likely to be considerably less than in other theatres of operation. He did, however, qualify his statement to say that he has no practical experience of such a use.

Owen, I wonder whether any of the moly products you list have additives which are not appropriate for our use ? Our problem is that manufacturers will not divulge full details for fear of compromising their competitive marketing positions. In the end, we are reliant upon our individual personal experiences. Many thanks for your comments and caveats.