What thread lubricant is hot these days?

Looks like the Silicone Grease - 5G that MTN sells is Super Lube.

It states:

  • Food Grade Grease
  • High Dielectric Strength
  • Excellent Heat Transfer Efficiency
  • Thermally Stable
  • Compatible with All Major Rubber and Plastic Compounds
  • Fortified with PTFE

Which is pretty much what Super Lube states on its website: SILICONE LUBRICATING GREASE WITH SYNCOLON® (PTFE)

If he’s using one of theirs, it’s not the most common 21030 flavor…that’s what nearly all the retailers sell (and usually that’s the only one they sell). The sheet you linked is a different product from them, though. I can tell you that in hand and in use, what MTN sells is nothing like the “normal” Super Lube grease. They have a couple dozen greases, though (and lots of oils). And there are still many suppliers for silicone greases - Super Lube doesn’t exactly have the market cornered there…quite popular, however. I love the stuff and it’s generally my go-to grease for all kinds of things although I have about five that all get regular use…but the 21030 Super Lube doesn’t see flashlight threads for me anymore.

Well hopefully the MTN version is compatible with silicone rubber, which is used with a lot of flashlight O-rings.

According to the Super Lube compatibility chart, the common Harbor Freight 21030 (3 oz) version is good with silicone rubber.

The 92003 (3 oz) version that I linked above is not compatible with silicone rubber. BUT, that’s unfortunately where the MTN description matches up with Super Lube.

Seems to be. I think I got my first tub from Richard maybe 4 years ago. It’s been on several lights with black and red “silicone” o-rings with no signs of change. I say “silicone” because who knows what type of silicone these china rings are made from…literally hundreds of formulations of silicone rubber in this range. The Super Lube was fine in that regard as well, and over a couple decades using that all over the place in bicycles, auto, and (non-critical) shaft seals, all of those rubbers were fine (I think mostly buna, epdm, and some plain vulcanized rubbers but lots of them are “who knows”…). When I run out of this last one from MTN I’ll pick up a different Super Lube grease…hopefully in a viscosity that’s a tad thinner than his. And some of their real silicone oil, too. The majority of silicone oils out there are actually petroleum based with just a tiny bit of oil-compatible silicone in them and they leave very little behind for lube, but the good stuff is awesome, and when it’s not too thin it’s a dream for lots of parts and shafts.

Most flashlight o-rings are not silicone, they are nitrile / buna-n. The green o-ring that sits on top of the glass window of an s2+ is silicone, but you wouldn’t lube that o-ring anyway. If it’s a black o-ring it’s most likely nitrile / buna-n.

Silicone grease is not compatible with silicone o-rings, but it is compatible with everything else. Silicone grease will degrade / dissolve a silicone o-ring over time.

Bare aluminum threads do this no matter what. I don’t think you’re going to find a grease that does not turn grey when used with bare aluminum threads. Ideally a light should be designed in such a way that it does not require bare threads, but instead relies on the bare ends of the tube wall to make electrical contact. Flashlight design 101.

Here is a pic of Tactical Grizzly’s recommended lubes. All silicone w different thickness and additives.

He mentioned that UV will reveal Nyogel 760g silicone thread lube.

I just UV checked the Nyogel 760g coverage on the threads of my light, and it looks good! :wink:
.

Yes, but some faster or slower than others and of course that depends upon frequency of use and oxygen exposure.

UV will light up most greases including those that have zero silicone in them. What color it fluoresces depends a little on other compounds in the grease (for instance a synthetic polyurea I have that is dark blue-green still lights up blue but a different shade). Good old white lithium is pretty bright…vaseline is so bright it’s almost blinding. I have some grease with silicone in it and it doesn’t light up at all (natural state is a translucent light amber). The red sticky bearing grease turns a weird shade of grey. Not sure how many of these may contain talc in the binder but that will sure add a lot to fluorescence.

The silicone grease from MTN does not fluoresce at all, not even a little.

correction
He mentioned that UV will reveal Nyogel 760g silicone thread lube.

I just checked, and UV does Not reveal Nyogel 767a
.

And regarding silicone vs nitrile O-rings, I find it interesting that Convoy states they are silicone:

This is what I ordered: 10g O-Ring Grease O-Ring Silicone Lubricant Silicone Faucet Grease Waterproof Food-Grade Seal Grease For Toys And Flashlights. $4.40 CAD from CN.

Super O-Lube.

I’ll report back.

don’t know how to post picture.

People overestimate how fragile nitrile rubber exposed to the “wrong” lubricant is. I’ve put lucas RnT on buna-n o-rings, including on flashlights. Hoppes. Mineral oil. I actually use RnT on all sorts of things people think it shouldn’t go on.

Super-inert nitrile and threads which have an expected lifetime of probably 5000 cycles are not worth spending too much time fretting over.

The stuff MTN sells in the little plastic tubs is good stuff.
I’ve been using it on all my lights for about five years now and it has not hurt any o-rings.

I am sure the Superlube is fine but I have not tried their grease but the SL oil works good for knives, wrenches, and pliers.

It’s good if you can make up your mind which lube you like the first time cuz chances are that the tube will last you the rest of your life.

LOL

the reason there are so many different aswers, is because there are so many different lubes, and people swear by the one they got, for a lifetime… LOL

apparently they all work

maybe asking which lube,
is just a way of asking for another excuse, to play with my toys again…

what lube should I use?.. :wink:

Interesting on the UV, i blasted my Jetbeam grease with it and it does fluoresce, though in the container it comes in the container fluoresces as well.
On threads its not as bright as the pic above but it is noticeable under UV.

Honda transmission fluid lights up a bright blue under UV light. Used it to track the leak to the Transmission Dipstick seal.

I have been using this DOW 111 silicone lube for at least 20 years.

It helps protect your orings so they don’t get abused from the cap being loosened and tightened. Plus you don’t get that fingernails on the chalk board sound. As far as wearing the threads, don’t know.

I’m still somewhat new to flashlights. Currently have two Hanklights that are about 5-6 months old. I have yet to do anything with grease for the threads/o-rings. How frequently should new grease be applied? Does the old stuff need to be cleaned off first?

Often the threads and o-ring fit on our lights are imperfect at best, so lube helps to extend the life of the rubber, and on the threads it’s mostly a feels-better thing although if the threads are particularly crappy/rough it can aid in reducing tearing as those “wear in”, so to speak. With metal dust and/or oxidation most greases will discolor a little as you screw/unscrew the threads, and there can be some of that even just sitting over long periods of time, too. I think it’s more important to keep the grease away from electrical contact surfaces than it is to keep the threads looking clean/not grey, but it doesn’t hurt to wipe everything clean and apply fresh grease every so often. On often-used lights I think I do it maybe every 9-10 months or so and it doesn’t always require it. Other lights don’t see fresh grease for a long time. With whatever this translucent silicone grease is that I’ve used for awhile, I clean/refresh a lot less often than I used to with other greases (primarily Super Lube mentioned here but also the similar Tri-Flow and Napa greases and a couple others I tried over the years).

Most of the anodizing on our lights isn’t super hard or what’s advertised, but all anodizing does impart some surface hardness as well as sealing the metal from oxidation (the color and sealing are separate steps in the process but are one thing after it’s all said and done…and bare aluminum will oxidize (i.e. “rust”) on it’s own, which is kind of self-protective as opposed to the damage that we see with iron, copper, etc). Anodizing penetrates into the host metal, not sitting on top like an applied coating, so when you remove it you do remove actual metal. Whether that matters or not just depends on a number of things…generally it’s fine. I’m not sure how much actual metal may be removed with lye as opposed to buffing/abrasion, but probably a lot less. If you stripped ano from threads, it’s probably of no consequence but grease would be a better idea there just to help reduce oxidation…since it’s a moving part then the natural protective layer of bare aluminum will get continually abraded away, making the grease look dirty faster and accelerating the process. If the light is designed so that the current passes through tail cap metal into the tube via flat mating surfaces only (i.e. when the threads are anodized originally) then other than not being able to mechanically lock out the light with a twist of the cap, there’s no worry about future thread wear really, as long as the mating surfaces still meet when tightened. Some lights don’t anodize the threads and they serve as the primary path of electricity to the driver, so if threads get bad there (or if you use a grease that doesn’t conduct electricity well) then you’ll have problems with flickering and such eventually as those threads deteriorate. None of this is a really big deal, though…use the light, enjoy it, and if you ever run into problems then the basics of clean threads/mating surfaces and removing oxidized schmoo or metal debris is where to look first. That’s true with or without grease or anodizing.