Hey guys, ran into this forum the other day and thought I’d say hello. Thought you guys might be interested in my project (as I noticed a bunch of you have used QTC in other threads).
I’ve been working for a long time now on a light built around a QTC engine from scratch – trying to eliminate as many of the common failures of the material as I can. Also, this light is non-battery crush, so no rattling when it is completely uncompressed. I feel pretty good about what I’ve come up with so far. Here are a couple pics of my last 2 prototypes:
And a video:
I started documenting this project a small time ago on CPF as well if anyone is interested (and I think I can paste a link to the thread here, but if not, let me know and I will delete it).
That looks like a sweet little host you have there.
Just out of curiosity - since I've played with QTC a lot - have you managed to get any longevity out of it,
Max life span of my designs are 4 weeks of operation where it should actually be changed after 3 weeks for really good operation. I used that particular XML flashlight for about 2 days before having to recharge it, but with the variable output it does not say much about hours. But i gather around 3 - 4 hours every day.
So I gave up on it I must admit. But this design you've made sure looks good. Love to read more about it :-)
I’ve been able to get a good amount of longevity out of the QTC material (after many many failed attempts). In earlier prototypes there would always be artifacts that started to appear. Mainly because the material was receiving too much pressure too many times - leading to the flickers and less-than-reliable brightness change that many have described.
In my older models the QTC would develop these artifacts pretty quickly, but in the newer engine designs I’ve limited the amount of compression force the QTC takes, which greatly improves it’s longevity and performance. I’ve also added a fail-safe in the event of complete QTC failure. The light goes to direct drive automatically, bypassing the QTC, when it reaches maximum compression. Another good thing is that the QTC, even when mangled, still performs approximately as intended in this engine. This light should be very durable. I’ve eliminated as many parts as possible. It is designed to be quickly disassembled - similar to field cleaning a gun. I’m a big fan of minimal design…it’s down to only one threaded part and 2 solder points (and I want to get rid of those too lol).
This latest light after a couple thousand twists and several nights of full-on still acts as it should - one full rotation from dimmest setting to max. I’ll continue to test it until I can get it to fail somewhere, then hopefully fix whatever weak link pops up. Luckily it’s finally getting close to how I originally envisioned it.
Here is a video showing the fail-safe in operation (you can also see the wear it is getting from torture tests lol. Very durable so far). You can see the light jump up to direct drive when it gets near the end of the twist:
Thanks again for the welcomes, guys! I’m also working on a AA version of this light, so hopefully I’ll have some pics and info on that one soon too.
Yes, hopefully I can continue to tweak the design and get a run made soon. Talked to a few shops today about making some. Hopefully I can get the price right on them.
Did a drop test today to begin some durability testing. First drop was from approx 25 feet onto concrete. Light survived great (even though the impact sound made me cringe). Going to do a few higher tests next…
Here’s the video of the drop from 50+ feet onto concrete. I feel good about the engine durability now as the light seemed to survive no problem (other than some pretty deep scratches).
If you look closely you can see the light dropped right after I say “alright” (we jumped the gun a bit on the drop lol), and it hits the concrete path and bounces into the grass.
Thanks Yes, I anodized my own lights…although it took several attempts. The first few prototypes are done with GunKote, which is a bake on paint like you would see on gun metal. The last one is anodized - took some doing to find a power supply that wouldn’t self-shut-off with ‘smart circuitry.’ I’m gonna try to get the finish a bit more matte if I can.
!
