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General Discussion To Gateway To Airguns => The Shop => : mjb108 November 10, 2008, 10:40:13 AM

: Molybdenum
: mjb108 November 10, 2008, 10:40:13 AM
I’ve tried both Jim Macarri’s moly paste as well as Beeman’s.  I prefer the Beeman’s due to its thicker consistency, but I don’t know if this is better.  It just may be an uninformed impression.  Does anyone have an opinion on which is better?

Also, Wikipedia has an interesting article on Molybdenum for those interested, see

http://en.wikipedia.org/wiki/Molybdenum

This is sure more readable than the classic text MOLYBDENUM published years ago by the Climax Molybdenum company!  LOL.  I love the name of one of the ores - WULFENITE.
: Re: Molybdenum
: Graham November 11, 2008, 12:22:30 AM
Macarri's is best, as it contains 70% moly, and Beeman's is 60%.
: Re: Molybdenum
: Gene_SC November 11, 2008, 12:47:54 AM
Good point Graham, also the heavier or thicker the moly the slower the spring will work.

Gene
: Re: Molybdenum
: Gene_SC November 11, 2008, 10:08:16 AM


Like I said the thicker the moley the slower the spring will move. That is especially the case when shooting during the colder months when you are shooting outside. Velocity tar is so thick that it is even hard to get it out of the jar and even spread it when it is below 50 degrees out..:)





Gene

: Re: Molybdenum
: dave2288 November 11, 2008, 10:12:50 AM
but how much could it slow it down?  doesn't heavy tar only slow down a pellet by 20-30 fps?  thats not bad.

what exactly is the rest of moly paste, if its only 60% molybdenum?
: Re: Molybdenum
: mjb108 November 11, 2008, 11:47:23 PM
Dave, Good Question!  The rest is probably similar composition to most greases - a vehicle oil (e.g. petroleum, synthetic or silicone, etcl) and powdered thickener (e.g. graphite for black greases, lithium, aluminum, clay, etc)  The MoS2 in this case is an additive to those more fundamental components of any grease.

There is an excellent discussion of this topic in the McMaster-Carr catalog, an online version is at http://www.mcmaster.com , search on GREASE and click on the result "about grease".  (sorry, direct links to their catalog are somehow prevented).

Cheers,

Mike

: Re: Molybdenum
: mjb108 November 11, 2008, 11:48:21 PM
I was aware of that but the thickness makes me like Beeman's better.  Call me old fashioned.
: Re: Molybdenum
: mjb108 November 11, 2008, 11:49:53 PM
Gene, Graham, I had not considered that.  Are you guys putting 60/70% moly grease on springs or using macarri's tar?  I was using tar, but maybe I am missing something.  Thanks for the comments.
: Re: Molybdenum
: mjb108 November 11, 2008, 11:53:18 PM
Gene, Graham, Fix, I had not considered that. Are you guys putting 60/70% moly grease on springs or using macarri's tar? I was using tar, but maybe I am missing something.

Also, Jim Macarri tells me he no longer sells velocity tar, said it was too messy (?! I should have asked about that, I thought reassembling the inside of a spring piston gun was pretty darn greasy/oily/messy to begin with!).  Is there another source?  I just use the standard tar.

Thanks for the comments.

Mike
: Re: Molybdenum
: mjb108 November 11, 2008, 11:54:25 PM
Ahhhh...

Fix - please tell us about your "goo"...

Cheers,

Mike
: Re: Molybdenum
: dave2288 November 12, 2008, 06:01:09 AM
hmmmm....will moly work on the spring like tar used to?
: RE: Molybdenum
: CharlieDaTuna November 12, 2008, 07:04:03 AM

Wait a minute….. I must be missing something here, or perhaps it’s just a confusion between the moly and tar or maybe some do not understand the difference in moly vs. Heavy Tar or grease and their applications and I think that there is some misunderstanding about lubes and how they are used …. especially in springer’s. That is unless I and the old masters that I have leaned from have been doing it all wrong all these years.

Now it is my understanding that moly, whether in grease lube form or in a spray can or whatever certainly has little or no value when used on the spring in springer’s with the exception of the spring ends and thrust washers. Using it on the coils is a waste and does nothing for the most part.

Moly is used where there is direct and constant surface contact where the two surfaces move against each other in usually opposite directions or one surface is fixed. The moly acts like molecular ball bearings and is used very sparingly, and good moly is very expensive.  I use a 77% moly that is used in the Aerospace industry and cost about $150 for 16 ounces. It is used on the spring ends and in certain areas of the piston OD and in some cases, the rim of the seal as well as on some areas of the trigger and should be burnished in that area. I use leather for burnishing.

The coils of the spring should be lubed with Heavy Tar, Velocity Tar or something of the equivalent and just on the outer surfaces of the coils. Heavy Tar does several things including dampening the spring, reducing the slight friction that it may encounter if the spring has wall contact with the piston and reducing vibration and harmonics of the spring. But it has to stay on the spring and moly cannot do that because it is no where heavy enough or thick enough and just gets flung off fairly quickly.

I read posts where some talk about different moly lubes and how they use it on springs. It really has little or no value especially long term (above all Aerosol spray moly, a true waste of money) when it comes to internal mechanical performance.

And no Dave … moly will not work like tar used to and never will because it is a lube designed for totally different applications.

Just my opinion for what it’s worth.
: Re: Molybdenum
: dave2288 November 12, 2008, 07:21:39 AM
bob, then where do we get tar from if jm doesn't sell it anymore?  he was my source for lubes, and i'm sure many others used him too.

thanks for clearing it up, bob!
: Re: Molybdenum
: Splash November 12, 2008, 07:57:34 AM
JM still has the heavy tar, just not the velocity tar.
: Re: Molybdenum
: dave2288 November 12, 2008, 08:02:31 AM
...is there a difference?
: What is TAR
: kiwi November 12, 2008, 05:46:01 PM
Hi guys what is this tar?...is it a thick grease  dose it have any lubeing ability.
Because of everything I have read about it it dose not seem to be a REAL grease.
So if thats the case of the cuff I can think of 3 or 4 other replacements if it has a limited lube ability.
 ie....lanocote / rustveto..both very thick corrosion inhibiters with a limited lubeing ability.
: Re: Molybdenum
: Graham November 13, 2008, 02:25:01 AM
I use moly paste on pistons, guides, and spring ends. I use Abbey gun grease (UK PRODUCT) on spring coils. Charlie has it about right, as it should be! If you're putting moly along the length of the spring you're just wasting it, as it's for surface to surface contact areas. The tar or grease is used to dampen the sound of the spring twang!
: Yes, it is a lubricant.
: vinceb November 16, 2008, 01:32:36 PM
It's a relatively thick 'open-gear' grease that is used in industrial applications. The high viscosity and stickiness of it is meant to prevent the stuff getting slung off gears that are not encased in a housing of some sort that could catch a lighter lubricant and return it to the moving parts.