Nice! Good idea. Just this weekend I was reflecting on how useful it would be if more electronics could be easily exposed in a custom light without complete disassembly. Replacing or building a driver is something that we try to explain to muggles, but if you can show then a PCB with components on it, that makes the explanation much easier. Right this moment I don’t remember exactly what my idea was, but it wasn’t as cool as this one…
When you piggyback on to the M6 board you are using the 7136s to supply the current to the FET gate, instead of driving them directly like we do the 70N02.
UV can be very useful camping and exploring. Minerals light up in pinks, yellows and blues, scorpions light up pale yellow. Lots of cool things with UV but not much throw and as you noticed, not easily sourced. Very neat project. I hope someone puts it together and posts pictures.
I am going to order the PCBs next pay. I have an SRK that's been waiting for something different to be done to it.
I have the PERFECT heatsink for this
https://www.etsy.com/listing/85401509/copper-disc-20g-50mm-blanks-cutout-for?ref=sr_gallery_10&ga_search_query=50mm+copper+round&ga_ship_to=US&ga_search_type=all&ga_view_type=gallery
Bond that board to that copper round with alot of solder paste stuffed down in the vias! (well with a few holes drilled to make sure the batt+ didn’t ground out by accident 
[I really think this board needs it’s own thread!] seriously 
Regarding the 12.2mm tactical switch by Helios, how do I incorporate this effectively in a switch for a light that takes 18350’s etc.? I suspect that it is more complex than a simple swap. I am trying to make a light that can use the Star firmware in the version RMM did with the double click to strobe and the switch is my sticking point.
Helios' switch board is just a thing to mount a pushbutton on one side and wires (or header pins) on the other. Meant as a direct replacement for SRK-style lights.
Adding a side switch to a light that didn't originally come with one is a much trickier project. You need a pocket for the switch PCB to sit in, and then a button on top and an outer bezel to retain it all in the light.
I’m traveling right now, so I can’t measure but I was imagining that I might be able to remove the clickie from a solarforce or similar and measure the diameter of the board it’s on and tweak the gerber file to that diameter, order, solder and replace. Would that work?
The tactile switch board is meant for side button use. Would not work for tail clickies. I can change the diameter for you.
Thanks Helios, any suggestions for a tail clicker?
This RMM driver (double click for strobe) is meant for side button, right?
I’m afraid something different would have to be done for tail clickies.
I know I missed this somewhere? Where does the 130 or 100 ohm resistor go on the BLF17DD rev 2 to 4? Marked R3 or marked R4? There's no definite source to find out? Thought the assignment used to be on the OSHPark page for BLF17DD but it's not there. Richard's website has conflicting info - doesn't list it where he lists the parts assigned to the board, then does include a 100 ohm resistor in the kit -- but doesn't say where it goes?
If it does go in the R3 spot (guessing), then does the R4 spot have to be jumpered?
** wish there was a way to search within a thread, or at least get search results to link to a post. These large threads are a total PIA... If someone knows, please don't use post links -- just a post #...
Edit: Crap! think I answered my own questions by tracing the routes on the BLF17DD -- should be on R3, and looks like R4 is not necessarry to jumper out. Someone please confirm?
This is my first BLF17DD (I got 6) - think I'll take detailed pics when it's all tested...
Your correct, R3 is 130 (gate) and R4 is the pull down and can be left open. R3 if not used has to be jumpered.
You would need to make it so the batt is always connected and have to run a wire to the tail switch (which would go to MCU pin2, pressing the bottom would cause a short to ground).
You could also get a nitecore piston drive host (like my D10) to use momentary FW with a tail mounted “click” switch. If you did want to go that route I have THE board for you.
I built this, it is the V2, if it worked fine before I tried the v1;)
I uploaded the file eagle (sometimes no matter oshpark well all) maybe I should upload gerber files;
If you want you can improve PCB;)
happy to help communities BLF!
Thanks Killer.
OMG!! Built up a couple of BLF17DD (V2's I think??), put one in a SupFire L6 (C8 size head/reflector but uses a 26650). Wow, just wow! 1,462 OTF (I measured) from a XM-L2 T6 4C. I think I'm loving this tint... A KK 4200 gets 5.7A, a Powerizer gets 6.2A, LG HE2 gets 6.15A, and 6.05A for a Sam 25R.
The heat sinking is done up well (SinkPAD - GC Extreme - screwed down the SinkPAD - 1.5mm copper disc soldered to a brass pill top - thermal/electrically conducted greas on the pill threads), it sure gets hot in a hurry, so the heat sinking is working.
So this is tested?
The V1 was wrong The printing on the + and -
and the size of the PCB was 12, now it is 16mm
The V2 is tested and it is ok.
Same light with the same driver and an XP-G2 S2 2B has some nice throw, nice tint, pretty awesome at 4.66A, 943 lumens…emitter is domed. Those “copper” (brass) pills that I got with the light are threaded wrong, thought about forcing one in and brute force changing the threads on something but ended up leaving the aluminum pill in. Still get’s hot quite fast. Not so bad as the harder driven XM-L2 though.