Ok to use Krytox GPL-226 instead of silicone on disco internals ?

[ninsei]

Hi.  Got my hands on some Krytox GPL-226 and am about to re assemble my Disco tube.  Ok to use Krytox instead of silicone grease?  Seems like yes after reading a few threads on here.

[Motorhead]

As an o-ring lube ... stay with silicone grease.

[nced]

As an o-ring lube ... stay with silicone grease.

LOL....Krytox is made for lubing metal and orings!

https://www.chemours.com/Lubricants/en_US/assets/downloads/Krytox_Overview_LowRes_H-58505-5.pdf
From the above.........
"Compatibility with Elastomers and Plastics
Krytox™ base oil is compatible with all elastomeric seal
materials and engineering plastics . The limiting factor
when using standard Krytox™ with any material is the
thermal stability of the elastomer or plastic . "

Anywhoo, it's rather easy to demonstrate the poor METAL lubricating properties of 100% silicone oil/grease. Chuck a steel rod in a lathe or drill press, lube the rod with silicone oil, start the rod spinning and hold another piece of steel tightly against the rod, take note about how fast galling starts between the two metals. Krytox on the other hand is a great all around lubricant for metal!

[nervoustrigger]

True, silicone is not a good lubricant for metal-to-metal contact but it appears the context here is static O-rings (rubber-to-metal).  For that role, silicone grease is perfectly fine.  Krytox would be big time overkill.  I suppose if it's all you have on hand and you don't mind wasting it, go for it.  Personally I would reserve it for applications that would actually benefit from its use.

[Motorhead]

True, silicone is not a good lubricant for metal-to-metal contact but it appears the context here is static O-rings (rubber-to-metal).  For that role, silicone grease is perfectly fine.  Krytox would be big time overkill.  I suppose if it's all you have on hand and you don't mind wasting it, go for it.  Personally I would reserve it for applications that would actually benefit from its use.

Exactly .... absolutely NO reason to use a high grade LUBRICANT to ease assembly of static use o-rings.  Silicone is proven cheap & effective as any high tech lube such as krytox based lubes.

understand ED uses O-ring piston seals that are DYNAMIC ( In motion ) and silicone would be a VERY lousy choice in such a case as this.
But as stated ... static use = excellent.

[nced]

True, silicone is not a good lubricant for metal-to-metal contact but it appears the context here is static O-rings (rubber-to-metal).  For that role, silicone grease is perfectly fine.  Krytox would be big time overkill.  I suppose if it's all you have on hand and you don't mind wasting it, go for it.  Personally I would reserve it for applications that would actually benefit from its use.

What you say is completely true, however I do wonder if silicone grease/oil would affect the "metal to metal parts" if it migrated past the "rubber to metal" areas. Probably not an issue even if it did get in the "metal to metal parts" if those metal surfaces aren't highly loaded.

[nced]

True, silicone is not a good lubricant for metal-to-metal contact but it appears the context here is static O-rings (rubber-to-metal).  For that role, silicone grease is perfectly fine.  Krytox would be big time overkill.  I suppose if it's all you have on hand and you don't mind wasting it, go for it.  Personally I would reserve it for applications that would actually benefit from its use.

Exactly .... absolutely NO reason to use a high grade LUBRICANT to ease assembly of static use o-rings.  Silicone is proven cheap & effective as any high tech lube such as krytox based lubes.

understand ED uses O-ring piston seals that are DYNAMIC ( In motion ) and silicone would be a VERY lousy choice in such a case as this.
But as stated ... static use = excellent.

LOL....completely agree as long as the silicone stays on the "static parts". maybe it does since I have little use or knowledge about PCPs/CO2s. The original query was concerning the use of Krytox that was already in hand I saw no need to steer the shooter to silicone grease if he/she didn't already have some on hand.

[ninsei]

makes sense.  thanks folks.  it's all I have on hand right now and since it's rated for orings i'll use it.

[KnifeMaker]

If it does migrate, say into the hammer area, it can really slow down  the hammer, and also give erratic velocities.

Knife

[nced]

If it does migrate, say into the hammer area, it can really slow down  the hammer, and also give erratic velocities.

Knife

Hummm....I didn't know that! I've been using Krytox for a few years now and found it to be very resistant to viscosity changes.

Krytox isn't like the old dinosaur oil based molly tar that will thicken with age as the petroleum carriers outgas. Here is a pic of a tub of "tar" that got thick enough just sitting sealed on the shelf to support a socket head cap screw on the rim of the tub by just a couple threads on one side........
 
LOL....Krytox GPL 205 through 226 is practically useless for muting spring twang since it's not thick like "tar".

Anywhoo.....even if Krytox grease would migrate (not sure it does or if it would affect the hammer if it did), how does it migrate from a static oring seal to the hammer spring?

[nervoustrigger]

Yeah, Silicone grease is very viscous so you absolutely do not want it in the hammer area but it is not going to migrate there short of perhaps the valve O-ring blowing out.

That viscosity is one of the properties that makes it particularly good as an O-ring assembly lube.