lube on air cylinder threads
Moderators: pilkguns, m1963, David Levene, Spencer, Richard H
lube on air cylinder threads
In the Pardini manual with regards to refilling the air cylinders it states . ''keep the threaded portion on the connector lubricated with a simple lubricant" So we use a very little of what ? Thanks
opps ment to post in olympic pistol , well it is early here in NZ lol
opps ment to post in olympic pistol , well it is early here in NZ lol
lube
Not sure what they recommend, but I used a synthetic light grease that I use on my mountain bike. I think the brand was Pedro's. not that it matters, and a very small amount. Almost to the point I wasn't sure that there was any applied. It definitely reduced the effort required to hand screw the cylinder on.
This was on my FWB700.
This was on my FWB700.
be in the moment
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Re: why?
Errr... Isn't silicon grease exactly what you should use on O rings?rmca wrote:It destroys the rubber o-ring.FredB wrote:Why?David Levene wrote: DO NOT use silicon grease.
http://en.wikipedia.org/wiki/Silicone_grease
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Re: why?
It can cause cylinders to bind up solid.FredB wrote:Why?David Levene wrote: DO NOT use silicon grease.
The last time this was discussed on TT I think someone used the word "spalling" but I could be wrong.
Silicone grease is exactly what you want for O-rings.
http://www.amazon.com/CORNING-MOLYKOTE- ... B00B2OHYMU
The point is to use a lubricant that will not degrade O-rings, will not diesel under pressure ( causing a secondary detonation ) and lubricates the cylinder threads to prevent "galling".
Gort
http://www.amazon.com/CORNING-MOLYKOTE- ... B00B2OHYMU
The point is to use a lubricant that will not degrade O-rings, will not diesel under pressure ( causing a secondary detonation ) and lubricates the cylinder threads to prevent "galling".
Gort
Re: why?
Be warned; some silicone greases are rheopectic.David Levene wrote:It can cause cylinders to bind up solid.FredB wrote:Why?David Levene wrote: DO NOT use silicon grease.
The last time this was discussed on TT I think someone used the word "spalling" but I could be wrong.
and, when David mentions 'solid', he means REALLY SOLID!!!
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Interesting question. I wish manufacturers would give more explicit information. There are many materials in use for O rings. Some will be attacked by petroleum products. I'm not aware of silicone grease being incompatible with any O ring material (please correct me if I'm wrong - this is important!) and I've used the Molycote silicone grease recommended by Gort on all sorts of O rings for years without problem.
What worries me more is aluminium alloy threaded into aluminium alloy. I suppose the cylinder and housing threads are anodised, but aluminium and (some of?) its alloys can gall or cold-weld when threaded together. Anti-sieze compounds, also marketed as 'assembly pastes' containing a high concentration of molybdenum disulphide or graphite will help, but these will be based on petroleum grease, possibly incompatible with the O ring. Molybond GA 50 is available in NZ, over-priced, of course.
I've come across a range of silicone oils containing molybdenum disulphide, marketed as gun lubricants. Sorry, I can't remember the brand: it was in UK, ages ago. Sounds like it could be the answer...
What worries me more is aluminium alloy threaded into aluminium alloy. I suppose the cylinder and housing threads are anodised, but aluminium and (some of?) its alloys can gall or cold-weld when threaded together. Anti-sieze compounds, also marketed as 'assembly pastes' containing a high concentration of molybdenum disulphide or graphite will help, but these will be based on petroleum grease, possibly incompatible with the O ring. Molybond GA 50 is available in NZ, over-priced, of course.
I've come across a range of silicone oils containing molybdenum disulphide, marketed as gun lubricants. Sorry, I can't remember the brand: it was in UK, ages ago. Sounds like it could be the answer...
PCP Grease
Lupus professional, its been the recomended grease ever since PCP's came out, I think its PTFE based. I've also seen factory techs using it.
I've used it for years and had no issues.
www.lupus-pro.de
Hochstrasse 150
Willich
D - 47877
Not sure how current the details are as my tub is donkeys years old.
I've used it for years and had no issues.
www.lupus-pro.de
Hochstrasse 150
Willich
D - 47877
Not sure how current the details are as my tub is donkeys years old.
Steyr recommends "acid free Silicone grease", refer to section 9, page 38 in the manual.
http://www.steyr-sportwaffen.at/media/L ... E_c_en.pdf
Gort
http://www.steyr-sportwaffen.at/media/L ... E_c_en.pdf
Gort
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This is interesting. Although silicon grease appears to be suitable for the O rings, it's not suitable for the thread.
Problem is, every time the cylinder is removed the "psshhh" of air that escapes blows any lube that was only on the O ring on to the thread as well.
So, whatever is used really has to be suitable for both the O ring and the thread.
Problem is, every time the cylinder is removed the "psshhh" of air that escapes blows any lube that was only on the O ring on to the thread as well.
So, whatever is used really has to be suitable for both the O ring and the thread.
Thanks for replies, looking at both the pistol and fill adaptor the male threads on both have a very light film of a black grease like substance, applied at the factory . There are no visible O rings in either the cylinder, or male connector on the pistol, or fill adaptor
.I think the factory is referring to an anti seize product for the threads rather than O ring lube .
Anyway I must admit with all the PCP's in use i assumed there would be a commonly used process. A very interesting discussion. Thanks again
.I think the factory is referring to an anti seize product for the threads rather than O ring lube .
Anyway I must admit with all the PCP's in use i assumed there would be a commonly used process. A very interesting discussion. Thanks again
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See http://www.targettalk.org/viewtopic.php?t=39217
re- Galling and Pure silicone dive grease
re- Galling and Pure silicone dive grease
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In response to the original post you might be interested in Pardini USA's response (from Emil Milev) in this thread.
"You can use a drop of regular motor oil, not much."
Having used silicon grease (from a dive shop) on a Morini, with the resulting extreme difficulty in removing the cylinder after about a month of use, I won't use silicon grease on threads again.
My experience is obviously very different from David M's.
"You can use a drop of regular motor oil, not much."
Having used silicon grease (from a dive shop) on a Morini, with the resulting extreme difficulty in removing the cylinder after about a month of use, I won't use silicon grease on threads again.
My experience is obviously very different from David M's.