Long time lurker here. Decided to post this as I am very pleased with the way it has turned out.
I wanted to design a very durable, very simple light. I've always liked the simplicity of QTC and have always been driven away from drivers and PCBs in LEDs, so I decided to try and build a light based around QTC.
Here is what I came up with:
Took a lot of trial-and-error and several failed attempts, but now it ramps smoothly and seems to be extremely efficient. Abrasion wear was a problem at first, and I also wanted to do away with battery-crush design. After several prototypes, it finally functions as I imagined it with no wear. Also attached are a couple videos of it in action:
Anyway, thought you might enjoy and good to finally post!
Here is a video of the version 2.0 QTC engine. The single full turn makes ramping brightness so much easier, and now I've gone through a couple thousand turns on the old engine and figured out the wear points and feel good about fixing them. The lines on the prototype show where a full rotation achieves full brightness.
(9/3/2012) update: Drop test from 25 feet.
(9/14/2012)update: Finished the v3 engine and body design. below is a pic beside the v1 design and video of it against a tk41
5/4/2013 Here are a couple pics of the prototype progression. From left to right is the oldest prototype to the newest.