Silicon or what other oil?

[bigHUN]

This is a silicon gel I am using it for several years already, looks like a lifetime volume. It works flawless with orings over summer hot days, but during Canadian winter = sub zero C - it feels that I would need something thinner on orings and running.

I may wanna go with seasonal re-lubing if I want to shoot year around.

 

[mtnGhost]

This is a silicon gel I am using it for several years already, looks like a lifetime volume. It works flawless with orings over summer hot days, but during Canadian winter = sub zero C - it feels that I would need something thinner on orings and running.

View attachment 314742

I may wanna go with seasonal re-lubing if I want to shoot year around.

That's the same o-ring grease that I use exclusively for nitrile o-rings. It's rated to -50C/-58F, are you saying that your PCPs get that cold??

 

[2L8]

That's exactly what I use here in Colorado. It's good to -50C and has a pour point down to -45C
Would love to hear if there is anything better.

Patrick

 

[nervoustrig]

You're using the best thing you could possibly use. Silicone lubricant has better low temperature properties than the O-rings themselves.

 

[bigHUN]

I am happy with that gel but...
Noticed during couple of last air top-ups at my range that I got a leak up to some level of pressure, when it reaches that level the leak stops. The Leshiy2 Valve is sliding on oring, and most likely a spring pushing it away from closed until the plenum pressure over rides the spring. Also the Reg piston slides on oring.
I toke that Valve apart and had a closer look and nothing is wrong, put it back on and refilled in my basement @ 22C works fine, outdoors in subzero - leaks again up to a certain pressure then stops again. OK, different materials shrink with some different rate, but at this moment the silicon gel in subzero is my first suspect.

 

[beerthief]

This is a silicon gel I am using it for several years already, looks like a lifetime volume. It works flawless with orings over summer hot days, but during Canadian winter = sub zero C - it feels that I would need something thinner on orings and running.

View attachment 314742

I may wanna go with seasonal re-lubing if I want to shoot year around.

or you could move to a warmer climate ? just kidding . Canada is a beautiful place . crappy laws but beautiful place to be .

 

[nervoustrig]

I am happy with that gel but...
Noticed during couple of last air top-ups at my range that I got a leak up to some level of pressure, when it reaches that level the leak stops. The Leshiy2 Valve is sliding on oring, and most likely a spring pushing it away from closed until the plenum pressure over rides the spring. Also the Reg piston slides on oring.
I toke that Valve apart and had a closer look and nothing is wrong, put it back on and refilled in my basement @ 22C works fine, outdoors in subzero - leaks again up to a certain pressure then stops again. OK, different materials shrink with some different rate, but at this moment the silicon gel in subzero is my first suspect.

Bear in mind that while the silicone lubricant may (or may not) aid with consistency of the valve's operation, it does not influence the sealing behavior to any meaningful extent. Only the O-ring itself can prevent air from leaking, therefore I think the topic to explore is instead the elastomer of which the O-ring is made and/or its durometer.

 

[Bigragu]

Attila- try treadmill mat lubricant. That and divers silicone grease is all I use. If you’ve ever bought and used a regulator rebuild kit from huma, the silicone oil that comes in those kits syringes is the same viscosity.

I feel sometimes if we over lubricate o rings, the HPA against the over lubricated o ring can role or tilt slightly out of its groove, and cause a leak. More especially the DURO 70 rings

 

[Rob_in_NC]

I only use kerosene to lube o rings. I find that it only slightly melts the o rings and creates a better seal.


and in case anyone reads this and doesnt realize it's a joke... it's a joke.

 

[Elbowgrease]

I use diver silicone grease and radio control car silicone shock oil. You can get that in different weights.

 

[Airgun-hobbyist]

Several things come to mind with this intermittent leak. First, I've been told by a wise engineer and manufacturer that when the high pressure air rushes over an o-ring during filling or the like that it burns or burnished them over time. This in essence makes it slick so it doesn't seal well. On another note of interest, o-rings seem to get a memory of sorts from being in a particular state of compression, so it may be that they are not elastic enough any more under certain conditions. Environmentally, going from heat to the extreme cold probably sucks the elasticity out of the rubber just like they do with vehicle tires. So that could be it as well. Basically, the o-rings may just need changed out sooner on a Leshy2 in Northern climates.

 

[Rawroots]

Automatic trans oil is synthetic and works well for all conditions, just add a drop more often to breach oring, if you forget to bring on an outing just pull the dipstick on your vehicle for a drop or two.

 

[nervoustrig]

when the high pressure air rushes over an o-ring during filling or the like that it burns or burnished them over time

To the best of my knowledge, a fill port's check valve O-ring is the only one susceptible to heat damage in a common PCP. And only if filling from a tank, not from a hand pump or compressor. And even then, likely only if slamming it with a quick fill from low pressure. Essentially a very low but nonzero probability.

going from heat to the extreme cold probably sucks the elasticity out of the rubber just like they do with vehicle tires.

^ This. Elastomers become less compliant at low temperatures, and may not seal properly or may take longer to relax and conform to surfaces after having been cycled (e.g. dynamic O-rings on a regulator spool, bolt or breech O-ring, etc.). Material selection and durometer...

 

[Peashooter]

I also use super lube and have so for many years on RC stuff, i also have some oil on spray, and i have also used RC car silicone oil for shock absorbers as you can get this in several viscosities.

I also have another grease,,,,, its really thick but for this reason i rarely use it on small stuff, but for rubber seals on things that need to be waterproof i find it useful.