Lubing the piston

[Oneshotwillie]

When lubing the piston is it nesscary to coat the whole piston in a lite coat of grease or just the seal and other pieces that touch the cylinder wall?  I watched a vedio where the person coated the whole piston before sliding it into the cylinder and I was thinking maybe that is a waste of grease.  Thanks

[GumpIsrael]

I used a VERY light film of dielectric grease on my piston face when I installed it, and a light film on the sides. Seemed to work so far, IDK if it's absolutely necessary though.

[Springrrrr]

If the piston has buttons or a ring of delrin or another material that contacts the piston tube, there is no need to coat the entire piston, just the points of contact and the seal --  lightly.  If the piston rides in the tube along its entire length a VERY light coat of a high quality molly or Krytox would work well.  I have put a small dab on my index finger and spread it on the piston to the point it could not be seen, just its presence felt.

The more grease in the piston tube, the better the chances it will get in front of the seal and cause dieseling.

It sometimes becomes a matter of trial and error to find out what the break over point is between too much and not enough.

[SpiralGroove]

+1 Springrrrr,
It seems invariably,  I use a little too much lube, usually smelling the oil burning when shooting for about 100 shots.
For me, it's SuperLube w/PTFE (per CDT) in the compression chamber of all my springers and a little molly on the piston seal and piston in general.

[Privateer]

What Bob and Kirk said. +1
I did change to the Krytox stuff instead of Superlube though.

[SpiralGroove]

Jeff,
What are the positives of Krytox vs. SuperLube w/PTFE?

[Springrrrr]

Krytox, albeit expensive as that hot place down below, has been generally accepted as a non dieseling lubricant although the spec sheet says it is stable up to about 500 degrees.  The instantaneous temperature at the pellet port of an air gun can reach over 1000 degrees and I have heard it may be closer to 2000.

That is enough to ignite a mineral based lubricant, even molly grease but for some reason Krytox seems to just make smoke if applied too heavily.  That smoke has been said to be somewhat toxic in that it can cause respiratory problems although on the Dupont website the following is claimed.

Odorless and colorless
•
Inert, non-toxic, and nonflammable
•
Stable in 100% liquid or gaseous oxygen environment

Either way, it has proven itself as a very slippery and a fine lubricant to use in air guns.  Standard Krytox
grease is formed by blending PFPE base oil with polytetrafluoroethylene (PTFE, teflon)  powder.   PFPE identifies a family of synthetic lubricants entirely composed of carbon, oxygen and fluorine, belonging to the class of perfluoropolyethers.

So there it is in a nutshell.

[Privateer]

Bob's got all the info.

I can't say it's better then SuperLube myself.
I bought a small tube mostly to see if the Hype was worth it.
I gave half of it away.

Given I do have a few new Guns to do some work on I'll get a chance to check it out.

I'm still not sure the latest and greatest makes that much difference when you look at the costs.