Lubrication

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BTW, are you sure all silicone lubes are the same? It could be there is petroleum in some of those, too? Even so, I would bet that friction, caused by inadequate lubrication or by dirty, boken down lubricant, destroys O rings faster than does any petroleum in them. Has anybody just submersed an O-ring in petroleum based oil and seen how long it takes to disintegrate? That might be an interesting experiment.

Dunno about silicone lubes maybe having petroleum. The NyoGel noted earlier is a petroleum product thickened with silica, might be considered a silicone lube. I've checked Dow Molykote 55 and Permatex Dielectric Grease, both are pure silicone. The Permatex is cheap and easy to find at auto parts stores. Permatex Spark Plug Boot Grease and other similar products seem to be the same stuff in different packages.

Lubricants don't break down in a simple flashlight, unless you're using cooking oil. I'm more concerned about the lubricant attracting grit, which will wreck sealing surfaces.

There are studies of how long it takes for butyl rubber to fail with various chemicals, google around maybe.
 
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Silicone grease will definately thicken, as the tailcap on my surefire has noticably more resistance during cold as opposed to warmer weather. If that triflow stuff is butyl safe (I doubt it, but maybe?) then I'd like to try that as its supposed to be significantly trackier than most greases (which is good, IMHO)
 
You should use lubrication on your flashlights for two main reasons:

1- To protect the threads.
The constant twisting action will grind down the threads over time. You minimize this constant wear and tear by lubricating the threads. To a lesser extent you also want to prevent the threads from galling. You can use most any lube for this including graphite, silicone, petroleum based oils/greases, etc. Even teflon tape will work.

Galling/seizing of the threads is generally not of big concern especially with aluminum since aluminum forms a protective oxide coating. Titanium and stainless steel, however, are more prone to seizing, but you should not worry unless you plan on leaving your lights sitting around for 20 years or so unused. The exception being the titanium screws used on the clips of some titanium lights. Those will probably seize over time unless anti-seize compound is used.

If your threads are gritty, this is bad. Clean them out thoroughly and then apply the lube of your choice.

2- To protect the o-rings.
O-rings are lubed to keep them pliable. If they dry out, cracken and stiffen, they would no longer serve their purpose. Choice of lube, gets more complicated because not all o-ring materials are the same.

The most common o-ring material is Buna-N which is a nitrile based rubber which is resistant to petroleum based oils. Other common materials are EPDM (another rubber type o-ring), Silicone (red-orange color) and Polyurethane (clear white color). The only lubricants compatible with all of these materials are perfluorinated, Teflon type lubricants like Krytox. Silicone based lubricants are a close second and are compatible with all the aforementioned materials except for silicone.

But don't take my word for it. Look up o-ring chemical compatibility on google. Here is a link to the makers of Nyogel, Nye lubricants, which discusses chemical compatibility. Examine the lower left table. Note, perfluoropolyethers are Teflon like compounds, Buna-N is a.k.a. nitrile and the Nyogels 779 and 760 are synthetic hydrocarbon based gels.

In reality though, for our use in flashlights, it probably really does not matter what you use, as long as you use something. It is not like your o-ring will instantly decompose if you use an incompatible oil or grease on it. We are talking long term effects over the course of years. Chemical compatibility becomes much more important in higher temperature and pressure processes encountered in industry. However, I suspect for o-rings that are actuated constantly, like the ones used in the popular piston drive lights, it becomes more important to use the correct lubricant. It is also important to use the correct type of lubricant if you want to ensure the water proof rating of your light if you are a diver.

In summary, use a Teflon (perfluoro) based oil or grease on both your threads and o-rings. If you do not have silicone o-rings, you can safely use a silicone based oil or grease. If you have a current favorite oil or grease, go ahead and continue using that, it is much better then using nothing at all. Just keep an eye on your o-rings for extra wear and tear.
 
I use distilled water for a lot of things I won't use tap water for. But they're the same thing. "Synthetic" hydrocarbons aren't made from a block of carbon and a tank of hydrogen. They need to get hydrocarbon molecules from somewhere, and they get them from petroleum. The website you attached says they don't make their base stock, they buy it. It's made from petroleum and highly refined. This was the conclusion of the failed lawsuit by Mobil to stop everyone from claiming to have synthetic oil. The judge found that they were all just refining crude oil and calling it synthesized. So "synthetic" lubes are more pure than "natural" lubes, but basically the same chemical properties.

That's not quite correct. A true synthetic oil is actually made from methane (CH4) or carbon dioxide (CO2) or carbon monoxide (CO). No petroleum products are involved.

Here is an excellent summary of the differences between motor oil, synthetic oil and synblend oil.

Also, while a hydrocarbon is a hydrocarbon is a hydrocarbon, the chemical and physical properties of the oil can vary greatly based on the impurities found in distilled petroleum products. For example, taken from this website:

Without getting too technical, suffice it to say that synthetics have a much higher resistance to heat than mineral-based oils. Because synthetic oil is composed of molecules that are uniform in weight and shape, its heat of vaporization is much higher (more than 600 deg. F.) compared to conventional oil, which begins evaporating at temps as low as 350 deg. F. This added stability at high temperature means that your hard-working engine wont burn up as much oil- and that means less sludge and fewer varnish deposits in the engine.
 
That's not quite correct. A true synthetic oil is actually made from methane (CH4) or carbon dioxide (CO2) or carbon monoxide (CO). No petroleum products are involved.

I'm neither lawyer nor chemist. In Mobil's lawsuit it was revealed that none of the "synthetic" motor oils were synthesized from pure chemicals, it was much too expensive to produce that in quantity. Apparently the few producers of "synthetic" base stock are simply refining petroleum products, and the judge set a standard for defining "synthetic" as including refined petroleum. A hydrocarbon molecule is just a hydrocarbon molecule, no matter the source.

Also, while a hydrocarbon is a hydrocarbon is a hydrocarbon, the chemical and physical properties of the oil can vary greatly based on the impurities found in distilled petroleum products. For example, taken from this website:

I agree. I only use high-grade synthetic motor oils and lubes in my cars. The difference is slight chemically, but significant in long-term performance of the product, mostly due to purity and additives. But the most pure synthetic hydrocarbons in the world will still dissolve butyl rubber O-rings, perhaps faster than low-grade hydrocarbons.

We each have to make our choices on what lube to use, hopefully this information helps us understand the risks and benefits of our options. I probably have some facts oversimplified or worded poorly, but I think we have the gist of this figured out. There are forums devoted to discussion of oil, and many automotive forums have sub-forums for oil discussions, lots of information out there.
 
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In summary, use a Teflon (perfluoro) based oil or grease on both your threads and o-rings. If you do not have silicone o-rings, you can safely use a silicone based oil or grease. If you have a current favorite oil or grease, go ahead and continue using that, it is much better then using nothing at all. Just keep an eye on your o-rings for extra wear and tear.

Good information. I also figured we had Buna-N O-rings, but after looking into it I think we have Butyl rubber, which doesn't do well with hydrocarbons. Fenix assured me my light has Butyl O-rings, and they chose that material for good reason. I have three Ray-O-Vac 4W LED lights that arrived new with badly eroded O-rings. I suspect they used incompatible lubricant, no other explanation makes sense. So I will avoid hydrocarbons like Nyogel.

Also, our aluminum threads are anodized, that's aluminum oxide, a ceramic, same material as sapphire and ruby, commonly used in sandpaper. Not electrically conductive, but very thermally conductive. This hard anodizing is a denser and thicker anodize, and it's dyed black with ink. Ceramic should be compatible with any lubricant, the dye might not be, I'm hearing some silicone lubes are turning black, probably from the ink.
 
Aluminium lights = Nyogel 760G

Titanium lights = Krytox 50/50

Get a bottle each of the above and it will last you for many years...

I am curious about this post - what is the reason I couldn't buy some Krytox 50/50 and use it on all my lights? The reason I ask is that I have 3 Jetbeam lights that have the orange/red coloured O-Rings that indicate they are Silicone and may weaken/deteriorate with Nyogel. I have been thinking about ordering some Krytox 50/50 for use with all my lights if it would be safe to do so.
 
I looked up Krytox, wow, that looks perfect! Teflon should be fairly dry, have you used the stuff before? Where do you get it and how much $? Online it looks like a tube will cost as much as a decent flashlight.
 
I have been using Nyogel for maybe two years and the o-rings are still intact. I can replace them anytime for few cents. Buying a more expensive lube just to protect the o-rings is IMHO a waste of money...
 
I have been using Nyogel for maybe two years and the o-rings are still intact. I can replace them anytime for few cents. Buying a more expensive lube just to protect the o-rings is IMHO a waste of money...

I get Buna-N or Viton O-rings for a buck a hundred, but I don't have a regular supplier of Butyl. Where do you get the correct O-rings cheap?
 
Depends on the flashlight type. Lighthound has surefire and novatac o-rings in stock: http://www.lighthound.com/search.asp?keyword=o-ring - and some standard sizes. These are Nitril o-rings. HDS/Ra lights have standard size O-rings, the size is mentioned in the manual. There should also be a lot of them at dealextreme.com or you could contact the flashlight manufacturer or distributer.
 
I looked up Krytox, wow, that looks perfect! Teflon should be fairly dry, have you used the stuff before? Where do you get it and how much $? Online it looks like a tube will cost as much as a decent flashlight.

You can get a special blend of Krytox from the Sandwich Shoppe.

Krytox 50/50 is a blend of Krytox oil #101 and krytox grease #201. You should shake it well before use.

You can also get a small tube of Krytox #205 from McMaster-Carr. Item #10195K19
They also have the other Krytox grades available.

The higher the number of the Krytox grease, the higher the viscosity. I have used the Krytox #206 grease without a problem on my lights.
 
I am curious about this post - what is the reason I couldn't buy some Krytox 50/50 and use it on all my lights? The reason I ask is that I have 3 Jetbeam lights that have the orange/red coloured O-Rings that indicate they are Silicone and may weaken/deteriorate with Nyogel. I have been thinking about ordering some Krytox 50/50 for use with all my lights if it would be safe to do so.

Yes, you can safely use Krytox on all your lights. The main difference is in viscosity. I find that the krytox 50/50 and the PTFE oiler from radioshack lubricate too well and make the threads on some of my lights "too loose". For example, on my nitecore D10, the teflon lubes make the head twist very loose so I stick to using the Nyogel. Though I do use the krytox on the piston which gives me a nice smooth action. On my Ti lights, where the threads are much tighter, I use the Krytox exclusively and it works well.
 
Yes, you can safely use Krytox on all your lights. The main difference is in viscosity. I find that the krytox 50/50 and the PTFE oiler from radioshack lubricate too well and make the threads on some of my lights "too loose". For example, on my nitecore D10, the teflon lubes make the head twist very loose so I stick to using the Nyogel. Though I do use the krytox on the piston which gives me a nice smooth action. On my Ti lights, where the threads are much tighter, I use the Krytox exclusively and it works well.

Sometimes, I use a different lubricant for the O rings than I do for threads. I love the PFTE Oiler for the threads and even for tight O rings, but if the O rings are a bit loose, I prefer thicker silicone there to insure water proofing, and continue to use the PFTE oil on the threads. I don't know if these lubes mix at some point, causing problems, but so far this works for me. BTW, isn't PFTE another name for Teflon?
 
I used to work with ultra-high-vacuum chambers and pumps, I think those were full of Krytox oil. Kinda thin for this maybe, but I might be able to score some vacuum pump oil for free. I can't justify buying a $50 tube to lube my $42 light. For now, I'll stick with my silicone dielectric grease.
 
Kingfisher, I have deleted one of your posts above. It was totally unnecessary, offensive and coarse.

Such posts will not be tolerated here. You are warned that any further posts of that nature will result in your posting privileges being suspended.
 
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