Hello all, I would like to use a 2 C mag as a host for an XHP70.2 and two 26650 rechargeables. Between mtnelectronics and adventure sport, I have found the led mounted to a mcpcb, driver and info on upgrading the electrical path. The problem is that I haven't found a heatsink with a price I consider reasonable. I searched through the old H22A posts but it seems like that seller disappeared years ago.
Is adventure sport the only option for a heatsink now?
Hi,
This isn't going to work quite as you have anticipated. A "c" body is almost big enough in diameter to insert a 26650. Almost is not going to do it. Even if you did bore it out, the length is too short, as a 26650 is about 5/8" (each) as a "c" cell battery. However, all is not lost! A 2D Mag works just fine, I've built a bunch of them. Take a maybe 4" long piece of PVC, slit it up one side, and it becomes your battery holder.
Now, mostly I've built these things DD. Don't freak out, it works. One very knowledgable person told me running 8.4 VDC through a 6 VDC emitter would blow it up. Not so, because the voltage we measure with our meter is almost a no-load condition. Once we throw an actual load on the battery(s), the voltage sags. There's a pretty wide range between enough voltage to turn the emitter(s) on, and too much which frys them. What I am suggesting to you, 2x26650 works with XHP50s, 70s, and probably a lot of other stuff.
As for heat sinks, I built a bunch of them out of aluminum before I retired; alas, they're mostly in builds, now. So, as an experiment, I took a 1" copper pipe end cap, and soldered a 3/8" end cap on top. I filled the bigger cap with old lead wheel weights (solder will probably work as well), and used an emitter on a 16MM round. I cut off the cam portion of the reflector, and opened it up slightly so that it would slip down over the PCB/upper heat sink. Worked fine.
The rest is details, running the + wire from the switch to the emitter, and I use a small terminal on a wire, clamped in place by the switch screw, to run to the - of the emitter. The worst, most tedious part of this whole thing is wiring up the switch.
As for no driver, when I'm building something like this, I don't care about anything but full throttle! But here's an idea: how about a triple XHP70? The dark lines and the center hole disappear when your emitters are 120 degrees apart on the heat sink. It works. The assembly is not in a flashlight right now. I was going to do it last night, got lazy.
Bob
