How often do you replace o-rings, clean threads, re-lube your lights?

Last weekend I went with my mother to her community pool. I removed my 4 year old Spark SL5 from its holster as I was changing into a bathing suit, and I thought of the brilliant idea of taking the light into the pool with me to check it's waterproof-ness.

Now....there are 2 possible reasons that the aforementioned "brilliant idea" was a failure: (A). I'd somehow managed to forget that I always back the tailcap off by approx. 1/3 to 1/2 turns, to prevent accidental activation(on a tailcap that tightens fully in just 1.5 full turns). (B). The o-rings were slightly worn and compressed.

One or both of those issues led to a few drops of water finding its way into the battery compartment, and some immediate malfunctioning of the light, which was easily dealt with by drying it out with my t-shirt.

When I first bought the SL5-210cw(XP-G), it's side switch was easier to activate than its identical rear switch, so I called Goinggear and he told me to return just the light to him for warranty or replacement. When he received it, he said he could just send me a new SL5-220cw(XM-L U2 version), with a ZL SC52 type beam profile. I agreed, but instead of just sending the physical light, he sent an entire new box with all the identical accessories I already had from the SL5-210cw, such as another nice holster, another diffuser lens, and all o-rings etc.

So after the pool incident, I decided to clean the threads and swap out all o-rings for new ones. When finished, it became obvious that the threads needed lube badly, but I had nothing aside from glycerin and a tube of -bearing- grease(correction). I opted for choice #2. I haven't done the water test again yet.

Where can you get extra o-rings that fit properly, aside from the manufacturer of the light? How often do you clean, lube your light's threads or replace o-rings? What common household lubricants can be used safely without damaging o-rings? What non-household lube is longest lasting and non damaging to o-rings?

I see this thread has a lot of views and no replies so I'll take a shot.

1st off... bummer your light was damaged but it sounds like your story had a happy ending, so all is not lost.

I don't heavily use any of my lights other than my Fenix E05 and Zebralight AA headlamp. So I've not had to replace any O-rings and haven't greased by threads either! :duh2:

I hate to hear that the half turn lock out could have been the cause. If that is the case, and the light this as a described lockout feature I'd have to imagine that would be considered a design flaw or defect if it is also advertised as water proof/resistant.

To attempt to provide some useful information- I cant see any reason why some common automotive grease or marine grease wouldn't do the trick.
If I felt so inclined to add some grease to my threads with something I currently have in my house I would probably use a small syringe of gun grease from my gun cabinet. I spent probably 8 dollars for an 8 oz syringe that is likely very similar to what I pack my trailer bearings with.

I can't speak to their quality or if they'd be the correct size but I know harbor freight often sells o-ring kits for about 7-8 bucks. Might be worth a shot if you need something now or just want to have something on hand.

my pool duty lights are all prometheus lights; which their construction goes above and beyond whats needed for a light to be pool proof in my opinion. however, i will still sit down with some cotton swabs, q-tips, and toothpicks to clean out the old lube and re-apply maybe 2 or 3 times a year. much of it depends on how much use theyve gotten used since the last time i cleaned the threads. more battery swaps probably means dirtier threads.

i do have extra o-rings that came with the lights but havent had to use them yet. the kind of lube i use is nyogel which can be purchased at oveready's site. a small tube of that should last you years. allthough i have no proof or evidence to back up my beliefs, i feel that nyogel has a thickness to it that if applied to the threads it will help block out any water that may get past the orings; as opposed to a thinner lube like nano-oil. as long as you keep some lube on light the O-rings should last a while. its only when things get dry that there might be some twisting and pinching of the o-rings when screwing on the tailcaps and what not.

tab665 said:

my pool duty lights are all prometheus lights; which their construction goes above and beyond whats needed for a light to be pool proof in my opinion. however, i will still sit down with some cotton swabs, q-tips, and toothpicks to clean out the old lube and re-apply maybe 2 or 3 times a year. much of it depends on how much use theyve gotten used since the last time i cleaned the threads. more battery swaps probably means dirtier threads.

i do have extra o-rings that came with the lights but havent had to use them yet. the kind of lube i use is nyogel which can be purchased at oveready's site. a small tube of that should last you years. allthough i have no proof or evidence to back up my beliefs, i feel that nyogel has a thickness to it that if applied to the threads it will help block out any water that may get past the orings; as opposed to a thinner lube like nano-oil. as long as you keep some lube on light the O-rings should last a while. its only when things get dry that there might be some twisting and pinching of the o-rings when screwing on the tailcaps and what not.

Click to expand...

Yeah I had the same thought about grease potentially adding some additional degree of waterproofing, above and beyond the o-rings alone. I read that lube should be applied all around the o-rings, including some lube under the o-rings. I just took a look at the tube of grease I used, and it's actually a semi transparent bearing grease.

I don't clean and lube threads at any definite interval. Rather, the frequency with which I clean and lube threads depends on the use of the light. One of my primary uses for flashlights is hiking. And because hiking is naturally a rather dusty activity, I might find that I need to clean and lube my threads quite frequently. I like to do it BEFORE the threads get to gritty feeling, as that gritty feeling means your threads are actually being ground away. Other lights used for other purposes (ie automotive work) may get cleaned and lubed less frequently. But I generally like to clean and lube before they get too dry and/or dirty. For lube, I use Superlube synthetic grease (which seems to be fairly popular around here).

As for replacing o-rings, I haven't really done this much. But I would do it when o-rings start to become frayed and/or stretched out. An auto parts store is a good source for o-rings. Some may be able to match up an o-ring, while others sell assortments that are not terribly expensive.

Probably not often enough.

Especially fresh, unsquished o-rings.

I dont have a schedule or any planned maintenance tbh, i tend to visually check the O rings and threads with each cell swap/charge. When new, they are cleaned up, O ring removed and a blob of nyogel massaged onto the O ring/s. I do this simply because you cant get the full O ring protected on the light. Once done, re-fit, couple of small blobs on the threads and work the tail cap a couple of times to lightly spread. Any excess removed(not usually as i go sparingly) and job done for the foreseeable. I have noticed bare threads can get a gray pasty gunk over time( one xeno light almost welded together that had been left for a good while !), this is cleaned off and again a couple of small blobs on the threads.

I don't recall replacing any O rings. I clean threads when they seem dirty. When the light is squeaking I apply nyogel.

Never

You're supposed to clean & re-lube?

Rarely, I add nyogel on aluminum lights when dry.

To be honest: too rarely. I am too lazy in this matter and it's the same with the care of bicycle chain and gears.