My mini GT was in pieces. It started with a severely unresponsive switch, and Neal asked me to find out where the problem was. So I opened the (unglued) bezel and because the centerpiece was so tight in the reflector opening, the unscrewing of the bezel twisted the led from its solder pad. So I had the mini GT in pieces with two problems now. I ordered a batch of new switches from aliexpress, which will be a separate project, but in the meantime I tried a dedomed XP-G2 S4 2B in it, recovered from a Emisar D4 in which I swapped the leds for warm white ones for a friend. The XP-G2’s seems the good old stuff. I reflowed one on the miniGT board and made a complete mess of the hot dedome (I started it too hot) lots of silicone left on top of the phosfor. So I heated the board up again, took it from the hotplate and started rubbing off the silicon from the phosfor with a wooden toothpick, trying to stay clear of the bond wires (hail my quality stereo microscope). Got most of it off with rubbing and blowing, but have some doubts if remains will shorten the lifetime of the led. Anyway, the led lives and worked surprisingly well in the miniGT, a perfect beam and 229 kcd on a 30Q at 30 seconds. Just the switch is still broken, it did not fix itself by disassembling the driver .You can see in above picture that the centerpiece tries to shear off the led again, but perhaps my reflows are stronger than Lumintop’s.
My USBasp arrived today, so I decided to take my Emisar D1 apart. Worked like a charm. Stupid thing is I’m still waiting for my SOIC8 clip. So I’ll probably order one from Amazon with evening express, cause I caaan’t waaiiiit now.
Always a good idea to number the cells and date them, so you can keep track of the characteristics and see if some rotation helps keep em balanced. I also like to write the IR on them from the first charge to be able to see if they are degrading over time and hard use.
This evening a second Nichia Optisolis mod, same story as my first but now in a Convoy S9, a bit more difficult than the S2+ build but the light will be a present so it needs USB charging. A 16mm XM Noctigon was first sanded to 15mm, bottom made very flat and edges rounded, this was done because it will be glued in later with AA-adhesive and the board must not make electrical contact with the housing. Then a solder-pad to the core of the board was scratched at the side. Then the two original +and - solder pads were connected with a wire. Then four 5000k Optisolis leds were reflowed on the XM-pads, the larger minus pads all facing inwards soldered on the central thermal pad, the smaller plus pads of the leds to the plus and minus pads on the outside.
Lots of re-trying, I had one led reversed it appeared :person_facepalming: , made a dirty job of the board eventually but in the end it worked.
The reflector had to be reamed to 8.5mm diameter, and slightly sanded on the underside afterwards to remove the sharp edge. It fits tightly around the 4-led array and I will not use a centering piece. The board is thicker than the stock board, that will compensate for not using the centerpiece.
The board was glued in with a led-tester connected to leds+ and head shell, so that a short between board and head would light up the leds, so I would be able during hardening of the glue to wiggle the board to remove the short. But all went well without shorts luckily, not the greatest thermal connection from board to flashlight but the current will be under 2 amps so that should be ok. The temorary plus-wire was removed and led wires soldered to the board.
I hoped for about 400 lumen and that is what I got: 390 lumen OTF (on a Keeppower 1200mAh 18350 battery, I made a S9 shorty). So that must be about 500mA per led which is good for a build like this.
I knew the glass needed heavy frosting but I still checked the beam.
The beam is not really bad actually, but the frosting is needed. Some heavy sanding with 180 grit 3M sandpaper later.
Almost perfect!
Checking the big smooth center of the beam:
The messy work did not ruin the light quality.
Finished!
Thanks, I didn’t think to do that. Now I have several sets of 30Q’s, I will do this soon, i still have them separate, but not with their new characteristics.
Thanks Dale (and Steve) The someone is actually my mother in law, it is her birthday sunday. She is an artistic therapist and does not get good daylight in her studio in the cellar of the house. This is solved by some daylight fluorescent tubes but it comes in handy at times to have some floody instant real daylight to check colours.
Btw, next to my ROT66, this light looks really green. Face it guys, reality is ugly green :party:
My Astrolux A01 quit working almost 2 years ago, and I had spare parts laying around from the v1.0 of my Booster Tails. So what to do? Create a basic boost driver for it! No MCU, no modes, no PWM… just nice, consistent output. It can technically handle a 10440 as well (input: 0.7 - 5.5 V), but I don’t see a need for that.
My 7yo needed a simple light for reading at night, so I dialed it down to ~6.7mA to the 219B for 3 lumens. I think that may even be too bright.
.You can see in above picture that the centerpiece tries to shear off the led again, but perhaps my reflows are stronger than Lumintop’s. 
