Lubricant for spar pins

On Saturday, January 6, 2018 at 8:44:13 PM UTC-8, Jonathan St. Cloud wrote:
Did a search of RAS and all the threads were quite old, so I thought I would ask what lubricant do you use when assembling your glider? I have noticed that the lube that comes with Schleicher gliders seems to have more friction and lube. Of course there is the old standby of white lithium, but any new ideas?



I have always used a molybdenum grease (aeroshell 33) for my main-pin. That is a grease intended for heavily-loaded pins in large aircraft. It's a grey grease, but it cleans up fine. I could only buy it in a fairly large tube, which has lasted me 15 years and the tube still has plenty left, even with me sharing the tube with a few friends. I also add a smear of super-lube grease to the main pin too. This practice has never caused me any problems. For other pins, I use superlube grease.

Another vote for Super Lube here. I'm convinced that the PTFE really makes a difference in ease of assembly. Plus it's a lot less messy than other greases I've used over the years.

wrote on 1/7/2018 5:15 PM:
On Saturday, January 6, 2018 at 8:44:13 PM UTC-8, Jonathan St. Cloud wrote:
Did a search of RAS and all the threads were quite old, so I thought I would ask what lubricant do you use when assembling your glider? I have noticed that the lube that comes with Schleicher gliders seems to have more friction and lube. Of course there is the old standby of white lithium, but any new ideas?



I have always used a molybdenum grease (aeroshell 33) for my main-pin. That is a grease intended for heavily-loaded pins in large aircraft. It's a grey grease, but it cleans up fine. I could only buy it in a fairly large tube, which has lasted me 15 years and the tube still has plenty left, even with me sharing the tube with a few friends. I also add a smear of super-lube grease to the main pin too. This practice has never caused me any problems. For other pins, I use superlube grease.

My ASH 26 E manual warns against using molybdenum disulphide grease (Aeroshell 33
contains 5% of it) on the main pins because it can damage the brass bushings in
the wing. So, be sure to check it's compatibility if your bushings are brass.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

Hi Eric
I see the Aeroshell 5% molybdenum disulphide grease is now sold as Aeroshell 64. It's widely used in aircraft. I wasn't aware of the Schleicher caution against it, and haven't seen any caution from SH. I wonder where Schleicher got their information. I don't see any problems reported when using it with brass in an internet search. There is a copper-corrosion test in the 21164 mil standard for greases (5% moly grease passes) but the real-world meaning of that test isn't clear to me.
regards



My ASH 26 E manual warns against using molybdenum disulphide grease (Aeroshell 33
contains 5% of it) on the main pins because it can damage the brass bushings in
the wing. So, be sure to check it's compatibility if your bushings are brass.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

On Monday, January 8, 2018 at 4:42:18 AM UTC-8, wrote:
Hi Eric
I see the Aeroshell 5% molybdenum disulphide grease is now sold as Aeroshell 64. It's widely used in aircraft. I wasn't aware of the Schleicher caution against it, and haven't seen any caution from SH. I wonder where Schleicher got their information. I don't see any problems reported when using it with brass in an internet search. There is a copper-corrosion test in the 21164 mil standard for greases (5% moly grease passes) but the real-world meaning of that test isn't clear to me.
regards



My ASH 26 E manual warns against using molybdenum disulphide grease (Aeroshell 33
contains 5% of it) on the main pins because it can damage the brass bushings in
the wing. So, be sure to check it's compatibility if your bushings are brass.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

Dry moly can cause corrosion, as it absorbs moisture from the air and the disulphide turns into sulfuric acid. Any good grease is a concoction of ingredients, some of which are inhibitors to make sure that doesn't happen. I believe the concern is theoretical, more than real.

On Monday, January 8, 2018 at 6:42:18 AM UTC-6, wrote:
Hi Eric
I see the Aeroshell 5% molybdenum disulphide grease is now sold as Aeroshell 64. It's widely used in aircraft. I wasn't aware of the Schleicher caution against it, and haven't seen any caution from SH. I wonder where Schleicher got their information. I don't see any problems reported when using it with brass in an internet search. There is a copper-corrosion test in the 21164 mil standard for greases (5% moly grease passes) but the real-world meaning of that test isn't clear to me.
regards



My ASH 26 E manual warns against using molybdenum disulphide grease (Aeroshell 33
contains 5% of it) on the main pins because it can damage the brass bushings in
the wing. So, be sure to check it's compatibility if your bushings are brass.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

I have seen molybdenum disulphide grease cause galling in brass parts on some pneumatic equipment. Moly is pretty much an "anti-lubricant" for brass.

We wax our pins twice a season, usually once before winter storage and again in the spring, mostly for corrosion protection. During the flying season we use whatever slippery comes to hand, usually the same grease as we don't use on O2 system parts.


--Bob K.

On Monday, January 8, 2018 at 2:33:59 PM UTC-5, Bob Kuykendall wrote:
We wax our pins twice a season, usually once before winter storage and again in the spring, mostly for corrosion protection. During the flying season we use whatever slippery comes to hand, usually the same grease as we don't use on O2 system parts.


--Bob K.

I've used plain old Vaseline petroleum jelly for 40 years or so with no known bad effects.
UH

Come on, the most important quality for main pin grease it that it leave a permanent circular stain on the thighs of your favorite flying pants/shorts - how else will other glider-guiders recognize you as one of the true believers at the field?

Even Pez D. Spencer knew that!


Ahhh, yes. The Schempp-Hirth sphincter kiss!

Thanks for the Pez reminder. Gotta check that out again.

On Saturday, January 6, 2018 at 8:44:13 PM UTC-8, Jonathan St. Cloud wrote:
Did a search of RAS and all the threads were quite old, so I thought I would ask what lubricant do you use when assembling your glider? I have noticed that the lube that comes with Schleicher gliders seems to have more friction and lube. Of course there is the old standby of white lithium, but any new ideas?

Super Lube for the pins, Tri-flo for everything else.. Lithium grease becomes lithium glue after a while...