Thanks, yes that does look like a thin and simple flashlight… great suggestion! Not sure how hard it would be either but I ordered one and am going to give it a try. Will try other lights too in the meantime if I find any promising ones.
Tried to crack open another LED flashlight and that one too was hard (didn’t succeed yet) to open.
Is this a common thing, for the LED part of the flashlight to be pretty locked up?
Olight I3e-eos is barely bigger than a AAA, weighs almost nothing, and can take a lot of abuse. I would check that out before thinking about building anything.
pretty sure the 348 unscrews at the head, it definitely unscrews at the tail
wle
The 348 is the slimmest AAA light with its 12mm diameter, but it’s 90mm long and not light weight because it’s stainless steel.
The Olight i3E is the shortest AAA light as far as i know, it’s only 61mm long (when turned off, 60mm when turned on), the head is 14mm wide.
The Olight is hell to modify, because it has the LED soldered on the driver PCB…
The 348 is a lot easier to modify, it has a brass pill with a driver PCB in the rear and a tiny LED board on the front.
The Olight i3E is absolutely not the quality of the i3S.
In fact, it’s a bit of a POS…
I killed the original Luxeon LED by twisting the head too tight (turning it on).
The Luxeon LED has a ridiculous footprint, so i was forced to spend hours fitting a 1mm XP LED board…
I had to sand down the driver PCB to about 0.25 mm thickness and had to make through holes for LED wires, etcetera…
A nightmare that fortunately ended quite well.
It now has a XP-G3 behind its TIR optic and reasonable thermal path to the battery tube when turned on.
I have the ‘silver’ i3E version (has a bit more power) and it’s pretty bright.
Anyway, some weight was added, but it’s still only 8 grams (0.28 oz).
They’re sold as Thorfire too by the way.
The SF348 weighs 26.1 grams (0.92 oz)
Thanks, I will check that out! But my definition of “weighs almost nothing” might be different from yours ;-).
Good to know. Ordered one.
Wow lots of good info here! Thanks. We’ll see what I come up with… will post the results at some point.
Have just checked on my scale, olight is 8g, aaa Nimh Duracell is 12g, and an AA alkaline is 24g. So the Olight with battery is lighter than a bare AA battery and looks like it is possibly smaller in volume, though slightly longer.
8g, that is pretty good for off the shelf. I’m using ultimate lithium batteries which are 7.77g on my scale… (are they well regarded in the flashlight world? …not exactly budget, but maybe they are when you factor in the value of long shelf life.) My hope would be to eliminate most of that 8g and bring the total weight including battery down to around 10g but we’ll see.
Just for perspective on weight, I recently made (well girlfriend did most of the work) a string backpack that weighs 10.61g including its carrying bag, and is capable of carrying my laptop, which is sort of a medium laptop in terms of weight (old 13” MacBook Pro). In its carrying bag it’s about the size of a walnut… outside of its bag it’s a little bigger than a laptop. Yeah I’m what they call a gram weenie.
If you take the head off the olight it probably weighs 4g, can’t check it right now.
That gives you everything you need except a return path for the negative at the back of the battery.
If you can make a spring mechanism that holds the battery in by pushing the back end, you have a functioning light at about 4g. The positive end of the battery will sit 1cm inside the head so it will be quite secure, and if you splay the head apart by 1-2mm an AA will also fit, giving you much longer battery life, but heat dissipation might be an issue unless you add resistance to reduce the current.
Yes that’s actually what I’ve been thinking! I got the copper one today, not going to destroy that one (it’s also heavy), but have an aluminum one coming in another day. Another idea is to cut away all but a couple thin rails of metal, just enough to hold the battery contact in place, and replace the missing material with light fabric.
This won’t be a light for daily use. It will be more just a lightweight part of a small kit… more as a backup than an everyday light.
Let’s see if I can do this image thing. Off topic of lights, but here’s the ultra-light string backpack:
Compared with the weight of some US coins:
Looks good. You can get something similar in outdoor shops here made of (I think) parachute material, also comes in a bag about the same size.
the singfire 348 does unscrew at the head, you can take the lens and the driver/led out and use in your bubble straw 
wle
Yes you should weigh one of them and see who wins ;-).
Nice. I have ordered one but it seems that the shipping will take a little while. Looking forward to it!
Well it arrived, earlier than expected, and I can’t figure out how to unscrew it at the head. Any tips?
Push the head on a rubber surface and twitst the body
I had a few that wouldn’t unscrew either.
I used pliers because nothing else worked.
Yes, it did leave some tiny marks…