Nice extensive tutorial Firelight2. Because I can’t stick to minding my own business, here are some additions:
*the solder iron for this purpose (unsoldering led wires and reflowing leds by heating the board with an iron) must be clean and hot, and for this purpose the tip must be preferably of the chisel type. A 18W pointy solder iron is fine for soldering components on boards but not enough for this.
*when heating the underside of the board for reflowing leds, first load the tip with a blob of solder, to help the thermal contact between board an iron
*even if there is enough solder left on the pads of the board, I still apply a bit of solder paste on all the pads, the flux in the paste will help wetting the fresh solder pads on the new leds and the metal will bond better, it will prevent eventual cold solder joints.
*after reflow and seeing the leds jump into position I gently tap the top of the dome of the leds with a tooth pick, some solder may squeeze out under the leds and the solder layer will be thinner (better heat path)
*I found a cheap led tester very convenient to test reflows, I have this one, but I swapped the momentary switch for a clicky switch to have both hands free.
That looks great! So how long did you wait for the GITD ring to “fade off” from light exposure before taking that photo? If the tritium is strong “just” enough to cause some illumination of the GITD ring, that’s really cool. And innovative — haven’t seen anything like this before. I may end up not waiting and getting a GITD insert to do this mod.
I bead blasted mine ( completely stripped the light first) so I don’t really know what caustic solutions will do to the threads. I would do what you can to protect the threads. Bead blasting is hard on the threads, you will lose the smoothness and have to polish them to gain the smoothness back. So I keep the light together with the o-rings and seal the open ends.
OK… so the trits actually might not have any noticeable influence. An hour later isn’t long enough to know if the GITD has totally worn off. I find that my Tec Accessories GITD key fob will be slightly glowing like 7 hours after exposure to a bright flashlight.
Ah yes, I’d heard about that. Well they do make UV emitters, but AFAIK they’re all the large 3mm and 5mm dome pin type. It would be cool if there was a micro SMD mounted LED that touches into the UV spectrum. And you wouldn’t need much power either. Maybe have them run at 20% of capacity? That would create quite the tritium light show.
Does UV exposure accelerate the half-life of tritium?
Probably not. The tritium half-life is a nuclear reaction. UV wavelengths don’t have enough energy to effect this process. The UV exposure may however wear out the phosphors in the trits which are ultimately responsible for emitted light. Not sure though what type of phosphors are used in this application. Some decay, others are fairly resilient.
Interesting. I know nothing about the phosphors used with tritium, but yeah that makes sense they might experience some degradation while radioactive tritium should be unaffected. Thanks.
Cool! The 0603’s look to be just about the right size. I can’t get over how small the 0403’s are. You’d need some pretty seriously precise equipment to deal with it!
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