Wire Glue - a perfect tool for DIY flashlight modders with actual test (picture heavy) and a little tutorial - how to

WIRE GLUE and one of it's possible applications for flashlight modders

The star of the show is wire glue purchased from ebay for a few usd. Ebay seller good-helper. Apparently it is a glue which when it hardens has aproximately the same effect as soldering. No special equipment needed (toothpick), not messy and no heat involved. Does it work? Read on...

The quinea pig for the test is a rather badly constructed but otherwise likeable single 18650 Q5 zoomie.

The 7W big sipik wannabe clone disassembled.

The head business. Notice the poor pill which is the big negative of this flashlight.

The bad quality stock pill. Note the bare negative wire that was pressed with the driver for achieving negative contact

to the driver. I do not like this kind of shortcuts, so off they go.

Emitter, foam padded and stock press fitted cheesy blinky driver:

Now onto reworking it. The emitter wires were unsoldered and wire glue was applied to improve the heat transfer from the

emitter to the aluminium pill. I applied some amount with a toothpick. Don't do it with other tools you still want to use one

day. On the right the replacement driver of choice the famous single mode 1050mA AMC7135 based linear regulator. I like

multimode drivers but for this one i opted for 1 mode only.

The glue dries pretty quick. Thermal conductivity is still to be determined but i expect it to be better than fujik themal

glue for this kind of application. In the meantime i soldered the driver wires and smoothened the edges of the driver with

some heavy grit sandpaper.

The wire glue has achieved some easy hardiness. Time to carefully solder the wires to the emitter. I use lead based solder

0,5mm thick with flux. Works a treat. Remember to always clean the tip of the soldering iron.

The pill almost finished with the driver pressfitted with help from heavy duty pliers. Used some clips to securely keep the

emitter in place for the wire glue to harden properly.

It is time for the final touch with wire glue. One of the most irritating "features" of aluminium pills is lack of soldering

possibilities since solder do not like to stick on aluminium. It is possible but it is really hard to do. Wire glue? No problem!

The application is strightfoward and really easy to do. It is really a pleasure to work with.

Some final assembly.

It is done. But will it work? Looks like it does.

It really does. (poor excuse to add another picture)

We can't really finish this without a beamshot... can't we?


The zoomed in beamshot i was unable to take. Due to the lack of more subtle camera adjustments i was unable to make one that would look

nearly decent. Actually i was unable to get anything looking remotely as square emiter die projection. On the beamshot the center portion is

lit pretty exaggerately. In real life it is not seen at all and appear rather uniform as with most other zoomies. Must be a camera thing or something.

All in all it worked out as i hoped for. The flashlight gets warmer faster even with less current fed to the emitter from the stock driver. This

translates directly to better heatsinking. I wish i had some matte black paint to coat the pill. I will do it at a later time.

The wire glue stuff clearly has some good potential in countless applications where soldering is not up to the job.

I needed approx. 1h to do it with picture taking included. Some of you would probably do it in much less time. But you probably do not have one

fluffy assistant that couldn't care less for flashlights and wanted some tender time just when i was in the middle of the project.

She has the power to turn me around her nail. Always. I had to do that right in the middle of the project only to end up cleaning

the flashlight even more than usually needed to remove all the tiny hairs she left behind everywhere. But she's so nice anyway

so i don't mind.

That's all folks!

Wire glue - highly reccomended!

When it dreis does not become an elastomer like the fujik glue. It's hard but not very much. Can be scrapped somehow easily (at least from a toothpick).

Didn't bother to draw a 10cm line and measure the resistance but it is probably minimal. If someone finds it highly resistive, thicker you go the less resistance

there will be. At least that i was being told in school.

That reminds me of the stuff that you can buy to fix broken rear-window-defrost traces on car windows. I bought of bottle of that stuff once and used it to fix a cut trace on a video card successfully. I wonder if it's the same stuff? What's the source and what's the cost? I like the idea of using it to adhere to the aluminum pills in cheap flashlights since you can't solder to them...

<Edit> Okay, I see the eBay link now!

The driver-to-pill connection is the killer app for this stuff. I have used the conductive trace pen before, but his appears to be of a much thicker consistency.

Thanks for sharing !

Additional testing for sag related to temperature. Minimal, from 18700lux to 18657 in 20 min. I tought i was gonna see some 25K lux. Distance si a little over one meter by eye. I guess the lens ain't that good and the emitter is a poor Q3 probably. Flashlight body temperature 40C by IR thermometer and my hand agree with that value.

Not entirely convinced heatsinking is that good but the results are quite in line with that claim. I tought Q5's at 1A were hotter. I guess i got accostumed to XM-L's that go really hot and a Q5 does not even qualify as hot nowadays.

At last! My cat finally finds my hobby a little amusing.

Didn't last much time. I was barely able to take a pic. Would not have noticed if it was not for the weird flickering produced by the cat running in front of the flashlight. :)

This stuff looks to have a lot of possibilities. Thanks for pointing it out. :)

That looks like some really useful stuff. Like Chicago said, the driver to pill connection is the killer app for that stuff. If it is strong enough to provide some durability. Good thinking, thanks.

It might be good stuff for button less batteries. I get a little scared putting solder on them.

I have the same stuff from good-helper, and I am not so satisfied with it. The electrical conductivity is too poor, and not a strong glue, too fragile.

I just got the same stuff, same source this week.

FYI, it is very similar to the homebrew mixture I found a year or two ago when searching the web for conductive adhesive.

The guy had done a lot of experimenting and ended up using plastidip (yeah, insulator) and graphite.

This stuff looks to me like clear glue (very similar to clear contact adhesive) and graphite.

The thing is, it is cheaper than I can buy those two things locally and mix them together, so when this runs out I'll probably buy more - well - that's assuming when I do some resistance tests this weekend, it has at least fair conductivity....


It is no magic material. Graphite (fine powdered) witjh some glue added. It has it's own uses however where classic solder fails or it is not really pratical. If you don't go microscopically thin there is almost no chance of poor conductivity. What currnet would sustain is however another thing. It seems it does conduct heat rather well. Graphite aint a bad thermally conductor at all. Would love the strength of the glue would be harder (epoxy?).

But mixing graphite micronized powder with epoxy would get a similar result.

I'll use it to pot drivers.

your drivers will short circuit and it is more expensive than proper potting epoxy

I researched potting recently after failing to pot w/ fujik thermal glue

devcon 2 ton epoxy and alumina is the popular diy mix on cpf, and apparently used professionally by some custom makers

mg chemicals makes some potting epoxies - slightly more expensive than that mix, and by my estimation (based on devcon spec and alumina properties) slightly less thermally conductive


much handier than mixing your own - although they could have done much better w/ the container. I was thinking of getting a syringe, sucking the glue into it and then putting that in a suitably sized sealed, well sealed container (cigar tube?)

+1!!! Do NOT pot your drivers with this!

dthrckt, how did your potting with Fujik fail? I use it all the time with no issues at all.

not really sure - it was a big ol' DX sst-90 driver - it could be that it hadn't fully cured in the middle - maybe it is a little electrically conductive in that state?

it could have been coincidence (it worked before i potted but only for a second or so after I did)

Even if it didn't cause the failure, I figure it isn't worth the effort. I had to apply it in several stages over a number of days (or it wouldn't have cured in the center for weeks, if at all). And since fujik essentially air dries, it doesn't lend itself well to being used in a mold.

I got 9oz of devcon epoxy for $18 delivered and 12oz of 8micron alumina for $15 (which is also a great, very fine, lapping material).

Awesome find, ordered straight away!

Think this conductive glue can be used to connect 18650s for a battery pack?

I'm going to rebuild my laptop 6-battery packs using panasonic ncr, just ordered them and still in shipping.

Rough estimate - current needed for the pack should be around 1.2A - 1.5A.

If this glue would work, I'd definitely prefer it, at least it eliminates potential soldering heat issue for the batteries. The problem is, would it hold the battery tabs well, and would it conducts sufficient current? Any thoughts?

I think you could fix a wire w/ this stuff and then reinforce it w/ epoxy, but you'd have to be very careful reassembling the packs if you just use the glue. if you apply too much at once it takes a very long time to dry.

edit: btw, this stuff works great for connecting driver mode star to ground on 105c drivers I have. last one I just went ahead and assembled the light and after about 10 minutes of use it dried enough to be conductive and went from default to HML operation lol

soldering that gap isn't hard...but why bother...