Potting compound for building a tank light

Yes, I’ve read about that. It’s mostly because that would corrode the components from what I’ve read. I’ve seen most posts about potting and many are mainly doing it for heatsinking to drive their lights harder but non talk about potting for durability. Those that do never show or talk about the process of potting. :frowning:

What about using hot glue?

I used it on a bunch of those solar outdoors lights to keep out water.

Hi.
I’ve done a couple of my torches and it seems to work.

Hardware Store. ” Ceramic Epoxy”. It’s white.
Comes in a 2 x tube mixer. and takes a few hrs to set.
NOT a 5 min mixture.
I add enuff to cover base driver and partially UP the components, Not fully cover them.
You won’t get them out again It’s PERMANENT…
but you can see if you’ve cooked them etc.
I did an original old C8 with Q5 chip in there first.
then threw it against a brick wall and onto the ground half a doz times.
Well dented. and cracked glass.
But the light still worked incl the switching. L.M.H.Flash. etc.
So Potting seems to give more electrical stability.

I’m quite sure that’s not going to do it. Hot glue melts at a fairly low temp and it’s going to melt when the light is on for long periods of time.

Above… YEP….

Tried on a $2.50 Speshul yrs ago.

Even without potting mix a 7135 driver will take a beating no issues. It has nothing to big sticking out to break of. You see the most issue with boost and buck drivers.

Hmm, thanks for the info. I’ll try to look for that. I’ve seen the abuse the PFlexPro lights take and was inspired to make one myself. Would be nice if it could be used on a 12 gauge once potted. It’s always much more satisfying when you have something you built.

You can get low / high temp glue. I think the low temp melts at around 80 degrees Celsius shouldn’t be much of an issue?

Macka17, the only thing that’s really popping out in my search is porcelain chip repair 2-part epoxy, does that sound right?
I’d be fine just putting some JB Weld or any old 2-part on there but I don’t have the depth of knowledge a lot of these folks have and you’ve actually used this with no ill effects.
Somebody was talking about acid or something eating away at components and then I realize this is beyond my scope.
I’d hate to click the switch when I really needed some light and get nothing!
I once dropped a light, it quit working, something rattling around inside. Potting is a great option if possible.

Also, I wonder if some epoxy putty like waterweld would work? It would be much easier to work with since it doesn’t flow.

YEP.
Bought to repair a china thingy of Missus’s Grandma. 7 pieces. fitted purrfect.

SHHH. Does good job, She ain’t noticed it yet. Over 150 yrs old luckily the breaks occurred between the glazed colouring so All white and blending.

I use it on boards to locate and stabilise all the little bits and their solder.
No Shaking loose or dry joint tricks.
Rather than protecting the internals of individual parts.

I would recommend simply silicone thermal glue. Not as tough against direct damage as epoxy, but still pretty tough and inside the light there should be no difference.
Thermally it should be better.
And if you screw something up or some component blows - you can remove it.

Do you have any brand to recommend? Might be a dumb question but it will cure like silicone and not so much like caulk right? I might get some Fujik to try.

I don’t know about any brands but I would recommend something that’s not just for waterproofing but also thermally conductive because there will be no air touching your components, so you need the potting compound to move heat away rather than insulate it.

No. I have Kafuter K-5024K and don’t recommend it because it separated into fractions, one white and thick and the other watery and translucent. I mix it up a bit before application and it works for me, but that’s not how it should work. I’ve seem many people recommend Fujik.

Isn’t air a thermal insulator already?

Oh dear, has it never occurred to you to search for “potting compound” ?

The proper stuff for the job.

Now, if you live in the UK, you can have almost anything available, in a couple of days, because we still do serious electronics here, and have a robust supply chain (for now).

E.g. https://uk.rs-online.com/web/c/adhesives-sealants-tapes/adhesives-glues/potting-compounds/

If you want to try to bodge things up with totally unsuitable “cheap” (not actually, when they fail) materials, maybe from a DIY warehouse, particularly any cheap silicones (more thermal insulator than conductor) that smell of vinegar and will corrode everything, eventually, well, you’ve got it wrong.

The thing is, that mixing up a batch of a good potting compound, even in a small sachet, is expensive, and you had better be prepared to use it wisely, which means more than just one hobby experiment. If this interests you, then you will need to do your own research, choose the materials that work for you, are available, and that you can afford (i.e. not only delivered in 1Kg tubs MOQ, like the professional ones).

Develop your own methods, experiment, don’t expect to get it right first time, or have your hand held.

Edit: did I also mention time and temperature ? Fundamental.

And it is mostly unnecessary, except for those of us who have an application for an assembly that can survive extreme G-force, repeatedly. Some do, and will pay for that assurance.

Pretty sure the OP wants to use his torch as a shotgun light, so extreme G-force survival is necessary for him.

I wouldn’t be asking if I actually found an answer. I live in SEA, which means it’s way harder to look for things like this and most of the time the only way is to ship from China since shipping from Euro or US is a pain. I’ve dug up all the old BLF posts as well about potting and non of them talk about making a light durable and most of them talk about heatsinking so I wanted to make sure.

Yes, I do know that real potting compounds are pricey, which is also one of the main reason why I’m asking as well.

Well, I would want to use it as a weapon light if it worked, so…

I live in SEA :question:
It would a little help, if you can tell us in which country do yo live.

In generall any epoxy glue without reinforcement particles should do the job.
I potted a lot uf switched buck/boost drivers with frequency up to 1.2MHz! without problems.

Today I buy epoxy for large jobs per kg, since its a fraction in price. (25 - 30 usd/kg)