How hard is building my own light?

Flashlight Modding and DIY Parts
1

I want a light with all of the following:
-Single CR123 size with pocket clip
-Mechanical clicky switch
-Single mode, 5 lumens tops for super long run time.
–3500k emitter
-Tough, waterproof, probably potted

Simple as can be for a durable, long-lasting bug out bag light. I haven’t found anything that fits this bill. So…

How hard is it to build one? Are there body/driver kits out there that I can customize? I’m quite mechanically inclined and have rudimentary skills for soldering and reading circuit diagrams. This would be a fun project to cut my teeth on.

2

You should get many replies on this one.
I’m not familiar with EDC lights, but this one may be close to your requirements.
The FW1A uses Andúril so you can program the output.

3

That meets… like, one requirement he listed? It’s larger than CR123 size (and won’t work hardly at all with an actual CR123 primary, even if you made it fit), doesn’t have a mechanical clicky switch (it has a momentary e-switch), is… difficult at best to configure for one-mode and still leaves in a lot of other stuff unless he wants to flash something to it, and I wouldn’t call it “tough, waterproof, probably potted” either.
But a 3500K emitter is easy.

Anyway, eicca: Your best bet is to pick a host you like in 16340 size. From there, getting a one-mode driver and 3500K emitter is easy. Most lights in that size will already be pretty water resistant (I wouldn’t dive with them) and you can pot the driver yourself easily.

Here’s a search on parametrek’s flashlight database selecting 16340/CR123 for battery type, and tail switch. If you’re willing to go 18350 instead (a bit fatter), the Convoy S2+ becomes the easy obvious option to mod.

4

not hard at all, convoy s2+ with 18635 tube warm led sound like what you want, as far as 5lm, i think it may be possible with one of many firmware versions,

5

Does it have to be done via firmware? Wouldn’t a fixed output driver be simple to do analog style?

6

Hmm. Not sure. Even a dirt-simple, one-mode, 1x7135 driver would be giving you ten to twenty times the 5lm you ask for unless you got the single mode set at 5-10%. You could probably ask Richard @ MTNE if he can build that, but I don’t see a way to get it by any of the pre-configured options.

7

I obviously don’t know enough about driver circuits. It’s not as simple as just changing a resistor?

8

The “driver” could be as simple as a single resistor, set to whatever value you’d want to give you that 5lm.

Of course, as the voltage of the ’123 drops, so will the brightness. Benefit of that is that runtime will also be stretched for as long as you could tolerate the output as not being “too dim”.

I’d go for a low-Vf LED to maximise runtime.

From there, yeah, just throw it into a S2+ shorty and you’re done.

9

Just for perspective, how bright or dim is 5lm?

10

the old Maglite 2xAA lights were 9 lumens

9 lumens and 5 are visually pretty close

11

Ok, then I have to ask: What do you do with such a light?

12

When your eyes are dark-adapted, 5 lumens is a lot.

13

it sure would be, but lowest you can go with linear is 350ma, and that will be around 100lm. unless you build your own driver, or simply use a resistor in place of a driver. wont be regulated but at such low output it does not really matter

14

I’d say to you to look at this post/thread and eventually get in contact with gchart.

15

It sounds like I’ve got a lot of reading to do on drivers before I attempt this.