What thread lubricant is hot these days?

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.

I apply new lube when I notice that the threads and O-rings are looking a little dirty - essentially the lube has turned gray.

I wipe away the old stuff with an old cotton sock turned inside out and apply new lube with a toothpick. In the past I used Q-tips, but that left behind too many cotton strands.

Some flashlights need to be re-lubed more often than others. My ZebraLights have been fine for years.

I bought these from Amazon Germany (DE)
https://www.amazon.de/gp/product/B07NV286LG
They don’t shed like cotton buds and are conically shaped making it easier to get right into the threads.They come in different lengths or an assortment.I initially used them for cameras but they are equally useful for torch threads.

The fellow Stuart Toolguyd
Claims to use mascara brushes , I haven’t tried them myself, (I never remember to add them to an order)

Brushes
for a variety applications , glue, lube , touch ups

These swabs

These would go great with the lipstick holder I’m using as a battery organizer.

I find a tampon insertion device works great as a diffuser.