DIY Headlamp

I made this a few years ago. It uses a 1 Watt LED powered by a single Lithium AA using a boost regulator circuit. The main box is 2.5" x 1.7" x 0.9". Total weight including battery is 2.5oz (70g). Cost of parts was considerably more than $2.

I made this one out of two small LED lights and a headband. It works great and is bright enough for around camp, although it’s barely enough for night hiking on a trail. I got caught at night coming down from Vogelsang this summer and the batteries died just as I made it to Merced Lake. W/ new batteries it would probably be ok. Here’s a link if you’re interested in the details:

half ounce headlamp

Very nice work guys. I made one earlier this year that came in at 13 grams.

More info here: The O.R.B.

Very light: 4.5 grams (≈ 0.16 oz.).

The clothespin is used to show it works.

No secrets – stupidly simple:

…easily converted into one.

I like the simplicity of that. Looks like you coated the assembly with some liquid rubber type stuff? Does it stay on when pressed, or just when you hold it down?

Hi Steve.

I’m a great fan of “stupidly” simple items (fewer things that can go wrong). The idea isn’t mine — I used Rainmaker’s instructions. http://www.trailquest.net/TQaltgear.html#LED

There are several "encapsulation" ideas on Rainmaker's site. I used Method #2 first and afterwards dipped the whole thing in a kind of rubbery paint (thinned it a little). I don’t know the word but it’s used for waterproofing roofs. After letting drip down the excessive paint I only had to wipe off the LED “bulb”. If you go this route, make sure to use as little of the tape as possible; if you use too much, it will either show the wrinkles, or you need too much paint (both -too much tape and too much paint- will unnecessarily increase the weight).

It would be a bit more complicated to turn it into a headlamp because, as you mentioned, it doesn’t stay on if you don’t hold it down -I think you already supposed so-. This is my back-up lamp. My primary one is a Photon Freedom Micro, sewn to my hat (already posted some pictures of the way it’s attached — could repeat if required). If you’d want the light to stay on, have a look at this (no doubt it will be “a lot” heavier): http://www.instructables.com/id/Make-A-Mini-LED-Light/

Stuart, what chip did you use in that circuit? I've looked through that manufacturer's data sheets, and I can't find anything that matches.

–B.G.–

Hi Bob
It’s a LTC3490

Very interesting.

The bare chip costs $4 now, so I don't know if it would be worth my trouble to build one. I could probably do a printed circuit board in one square inch.

–B.G.–