Motor Casing Grease

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Conan4480

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Is there something that I can buy from my local autoparts store that I can use to lube the motor casings with?
 
I assume you mean the inside of the case or the liners to make cleanup easier and be able to extract the liner..

I use Synco SuperLube. I've never seen it at an autoparts store, though. I get it locally. You can also get it from Aerotech at their valuerockets.com website as well as online.
 
Slick 50...... "'ONE grease" ....500 degree grease. 3.00 a tube Available everywhere.

Was recommended to me by AMW/ProX. click on pic below for where to get.

Picture 3.png
 
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The previous two recommendations are both good and work well.

High-temperature bearing grease works very well, too. Just make sure you don't get a type that has metal in it -- apparently, some do, but they're labeled as such.

I think I spent $2 for the last tub of it I bought, and it's going to last a long time.

-Kevin
 
Thank You for that link Jim, I've had the same question for a while now. I will have to go out and see if I can find either of those now!
 
This is what in your typical "Premium" Brand Name Grease contains the following chemicals. (Superlube in this case)
Specific Chemical/Identity; Common Name(s)
SYNTHETIC HYDROCARBON, CAS# 68037-01-4, 70-80% (linear C10H20 molecule)
HYDRO TREATED POLYMER, CAS# 8042-47-5, 10-20% (Plain old white mineral oil)
ANTI-OXIDANT, CAS# 41484-35-9, 0.5-2% (3,5-Bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid thiodi-2,1-ethanediyl ester)
FUMED SILICA, CAS# 68611-44-9, 7-10% (same stuff you thicken epoxy with)
THERMAL STABILIZER CAS# 68648-89-5 3-5% (BENZENE, ETHENYL-, POLYMER WITH 2-METHYL-1,3-BUTADIENE, HYDROGENATED which is a fancy name for a THERMOPLASTIC RUBBER)
POLYTETRAFLUORETHYLENE, CAS# 9002-84-0, 0.5-2% (teflon particles)
POLYGLYCOL, CAS# 025322-69-4, 1-2% (common thickener, like in shampoo)
PROPRIETARY ADDITIVES, 0.25 -1% (whatever)

Really nothing special.

Synthetic Greases use an oxidation resistant single long straight chain hydrocarbon molecule such as Decene (C10H20), whereas regular greases simply use a distillation fraction of crude oil with an average molecular composition of ~C10H20.

Many greases add mineral oil, a stiffener like fumed silica, an anti-oxidant, and a thickener like polyglycol to give the lubricity, viscosity and long-term thermal stability you need in a car where the lubricant needs to last for years. Teflon and the propriety additives simply make each produce slightly different and gives an excuse to raise the price. (Product differentiation mean high prices - Economics 101)

Synthetics make a big difference and save money in the long-term in automotive applications where the lubricant must not change properties for years and in that application are worth the extra money. For lubing a motor casing, you simply need something that doesn't pyrolize too badly when subjected to temperatures of 200C-300C for a few seconds so virtually any stiff grease will do with the exception of Krytox (R) or any perfluorinated grease. Perfluorinated greases can react violently with aluminum at high temperatures and should not be used in rocket motors because fluorine is a stronger oxidizer than oxygen, and even the PTFE in the "premium" greases is not a really good idea.

Bottom line. Don't think because you're paying a premium price for a "premium" lube you're going to get better results removing the liner because you won't.

Bob
 
Bottom line. Don't think because you're paying a premium price for a "premium" lube you're going to get better results removing the liner because you won't.

Bob

Agreed.....another big, big factor often overlooked is: How easy will it clean up after use. I have used many types over the years and have settled on one [Slick 50] that not only does it job, but cleans up easily with just soap and water or baby wipes.
There are others, but I fly a lot of AMW and this is what they use, because of its ease in clean up.

Some of these greases get like glue after use and are a bear to clean up,requiring solvents to remove the residue. I don't even grease the liners any more.

Sand to fit, if it goes in easy, it will usually come out just as easy.

Only on certain large motors[ m's& n,s] I use it on the liners, and then VERY sparingly.
Grease's main function is to prevent damage to the O rings, thus sealing the closures.
It is the typical case of: a little is good, so a lot must be better. How untrue, but most must learn this on their own.
 
Dow 111, I use it all the time, mostly due to I got 3 tubes for a gift at X-mas 3 years ago, only have 1/2 tube left.

heard but never tryed the Slick 50, Maybe I will try some
 
I use plain ol' Vaseline, and have never had a problem. Granted, I've only flown 24mm and I don't usually grease the liner (terrified I'll get it where it shouldn't be) just the O-rings, so YMMV.
 
I'd imagine vaseline will do more harm than good to the O rings. I don't have a casing yet but was just planning on using white litheum grease unless I get huge boooooos, from the crowd.
 
Dow 111, I use it all the time, mostly due to I got 3 tubes for a gift at X-mas 3 years ago, only have 1/2 tube left.

Dow 111 is really gummy and a lot harder to clean up than the products listed.

-Kevin
 
Actually the Aerotech instruction specifically mention Vaseline. It's all I've used on cases from 24mm to the I1299N in my 38/480 case. I only use it on the o-rings and threads. The biggest issues I've had is with the G motors in the 29/40-120 casing and their c-slot design. One side of the liner always seems to crack or burn through a little. Never hurt the casings, but I don't think grease would help that.

BTW, the only real problem I've ever had getting a liner out was in the only Loki snap ring case I ever flown. That was a I110W moonburner I used for my L1 cert.
 
Actually the Aerotech instruction specifically mention Vaseline. It's all I've used on cases from 24mm to the I1299N in my 38/480 case.

I've used Vaseline up to J350/J420 loads. Once I began flying larger motors (54mm J, K and up) I switched to the high temp greases. Now, I use the high temp grease on all loads because I always have it available.
 
@bobkrech:

Perfluorinated greases can react violently with aluminum at high temperatures and should not be used in rocket motors because fluorine is a stronger oxidizer than oxygen, and even the PTFE in the "premium" greases is not a really good idea.

that's interesting - I've always used either the Radio Shack teflon grease, or SuperLube, which is apparently the same stuff for 2x price. I have never seen any issues related to it reacting with the aluminum motor cases. but the cases are anodized, maybe that protects it?

the only trouble I've had removing a liner was the CTI N1100 out of the 98/15360 case. man that thing was just baked on.
 
Here is what I use:

You can find it at your local NAPA auto parts store, or what ever you have in your area.

The link to this on their website is:
https://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=BK&PartNumber=7651827&Description=Grease+-+Dielectric+Silicone

I only use a small amount on each of the threads, smear it around until I can't even see it, and then use what ever I have on my finger to grease the o-rings. Again, just enough to make them shiny. The tube is small, but with the amount I use with each application, a tube will lasts me at least one flying season.

Grease.jpg
 
Dow 111, I use it all the time, mostly due to I got 3 tubes for a gift at X-mas 3 years ago, only have 1/2 tube left.

heard but never tried the Slick 50, Maybe I will try some
Dow 111 is very good for lubricating o-rings and has a better heat resistance than hydrocarbon grease, but is awfully expensive for greasing liners, and doesn't clean up very easily as it's not soluble in most solvent.

[Note: You grease an o-ring so it doesn't tear or abrade when you install it. The grease does not make the seal. If the sealing surfaces are scratched or not smooth and clean, the o-ring will not seal whether you grease it or not.]

It contains the following materials:

CAS Number, Wt %, Component Name
63148-62-9, >60%, Polydimethylsiloxane (silicone oil)
7631-86-9, 7%-13%, Silica, amorphous (the stiffener)
70131-67-8, 7%-13%, Dimethyl siloxane, hydroxy-terminated (silicone rubber monomer)

Any silicone grease will contain similar components however the amount of silicone oil, silica and silicone rubber monomer will vary depending on the viscosity (stiffness) required for the application specified. Silicones are not water soluble, and don't dissolve in many organic solvents so they don't clean up well, but that's also why they are used to lubricate o-rings.

Bob
 
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I assume you mean the inside of the case or the liners to make cleanup easier and be able to extract the liner..

I use Synco SuperLube. I've never seen it at an autoparts store, though. I get it locally. You can also get it from Aerotech at their valuerockets.com website as well as online.

Saw this used by quite a few people at MDRA so it's what I bought.
What's Up Hobbies is where I got mine. What I like is the tube container is very durable so it stands up to being thrown in toolbox.

Works and cleans well so far.
 
I just can't see using hyper-expensive grease on o-ring that are used once. One time I had a copperhead fail to ignite a White Lightening load and it was over a month before I could get launch again. I had to dissemble the case to insert a new igniter, so the o-rings were effectively used twice. (well twisted on twice) And I saw no damage, before or after launch, from the Vaseline attacking the o-rings. The flight was prefect, so I'll continue to use Vaseline.
 
I use:



It takes just seconds to lubricate a motor case of any size. Once the solvents are gone it is basically the same as what comes out of the tube.

I broke down and used the web store to order this because I hadn't seen it in any local stores for a while. Of course the next time I was in the local ACE Hardware store it was sitting on a shelf mocking me.
 
I just can't see using hyper-expensive grease on o-ring that are used once. One time I had a copperhead fail to ignite a White Lightening load and it was over a month before I could get launch again. I had to dissemble the case to insert a new igniter, so the o-rings were effectively used twice. (well twisted on twice) And I saw no damage, before or after launch, from the Vaseline attacking the o-rings. The flight was prefect, so I'll continue to use Vaseline.

Hmmm. approx 2 dollars for small tub of vaseline vs 5 dollars for a tube of super lube.
Risking about 800 in rocket materials (my current 4" project) and dozens of hours of labor to using an inferior product to possibly save a few nickels a flight.... Superlube wins out for me.
 
Hmmm. approx 2 dollars for small tub of vaseline vs 5 dollars for a tube of super lube.
Risking about 800 in rocket materials (my current 4" project) and dozens of hours of labor to using an inferior product to possibly save a few nickels a flight.... Superlube wins out for me.

Bingo!
 
Sorry, sorry... didn't mean to offend anyone, remember I said all I had was 24mm casing. Granted I don't want to loose it, but Vaseline is mentioned by Aerotech and it works for me. I'm an unemployed disabled guy, I gotta be real careful with money. 50 bucks is a very expensive rocket for me. If I was spending that much cash on a rocket I'd probably buy expensive lube too.
 
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My apologies if I seemed a bit sarcastic, no malice was intended. I've seen and flown some very nice inexpensive rockets.

And my best wishes MKP, sounds like a challenging position your in right now.
 
Sorry, sorry... didn't mean to offend anyone, remember I said all I had was 24mm casing. Granted I don't want to loose it, but Vaseline is mentioned by Aerotech and it works for me. I'm an unemployed disabled guy, I gotta be real careful with money. 50 bucks is a very expensive rocket for me. If I was spending that much cash on a rocket I'd probably buy expensive lube too.

No offense. Vaseline is perfectly fine for those smaller motors. As I said previously, I've used vaseline on large 38mm motors without problems.
 
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Hmmm. approx 2 dollars for small tub of vaseline vs 5 dollars for a tube of super lube.
Risking about 800 in rocket materials (my current 4" project) and dozens of hours of labor to using an inferior product to possibly save a few nickels a flight.... Superlube wins out for me.

You make perfect sense, if your assumption that Vaseline is inferior in this application is correct. Other then opinions based on the "more expensive must be better" thinking, I've never seen anything that says Vaseline is any worse then any other lube, and some valid explanations why it's better then some.
 
Sorry, sorry... didn't mean to offend anyone, remember I said all I had was 24mm casing. Granted I don't want to loose it, but Vaseline is mentioned by Aerotech and it works for me. I'm an unemployed disabled guy, I gotta be real careful with money. 50 bucks is a very expensive rocket for me. If I was spending that much cash on a rocket I'd probably buy expensive lube too.

Vaseline does work; lots of us (including me) have used it.

My primary reason for moving away from it initially is that it liquifies at such a low temperature, causing it to get everywhere you don't necessarily want it.

-Kevin
 
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