Nice Jos, perhaps I will be able to use these in triple configuration as a food warmer, to keep fries hot or something. 
Overall beam profile looks nice to me, should be a pretty good general purpose light. Especially when the sidewalk is snow covered, your way will be cleared as you progress along. lol
Checked the mod with A123 LiFePO4 cells and the result is a bit disappointing: 1300lm at start, 1100lm at 30 seconds.
M2 Quad with dual switch:
I’ve found that for exploration underground I really like the side switch functionality as the light is much easier to hold and change modes, and as I like the size of these single cell Convoys it was time to build a quad with this configuration.
It’s the first light I’ve built with my v4 series of drivers that utilizes the OTC less design for off time measurement. Off time timing is now much more precise, not affected by voltage differences or heat.
The driver of choice for this light is my F2, a single sided driver with a SIR800DP FET and two AMC7135s (each on separate channels):
Instead of a spring I have the bare wire from the LED+ through a via which is coiled on the back side, soldered to the + pad and filed down. E-switch wires pulled out through a drilled hole in the side:
Nice fully rounded switch for the drilled hole. I had to pull out the legs a little so the opposite side of them wouldn’t have contact with the host:
The round switch is a snug fit:
I think this light is going to replace my old work hoarse (S3 triple with dual switch). Next weekend I’ll be breaking it in underground so I guess I’ll found out
Nice mod, where did the switch come from?
Thanks. I got them from here: https://www.aliexpress.com/item/Japan-Alps-SKRGAAD010-ALPS-Tact-Switch-6-6-4-3-feet-black-button-buttons/32373430664.html
Says that they are no longer available though.
I ordered others before, but the buttons that arrived where white, not black. I just searched for SKRGAAD010 switches.
Built a 26650 Triple.
Eagle Eye X7. Used Kiriba-Ru copper spacer with XP32 MCPCB soldered to it with MtnE reflow XP-L HI V3 3C on top. Used MtnE 20mm Fet+1 Bistro, springs bypassed.
Copper spacer thermal paste into head. Triple does well with this light. Feels great in the hand with the tube length and diameter, Full grip on the light.
Older SolarStorm K2 26650 same as the FandyFire K2. Recently acquired 2 of these… Nice light for a few years old. Like the green and red Leds under the E-Switch for battery status indication. Simple emitter swap to an XM-L2 U4 1A on a 26mm Maxtoch. Well not really a simple direct fit as I redrilled and tapped holes to 3mm and decked the top of the insert flat.
Fought to get this thing’s tailcap off, but finally prevailed with a scratch on the tail. Bypassed the tail spring.
Kept the driver original and it pulls 2.4A on high, will run for 2.5 Hours on high with a 5000mAh battery until light turns red. Forgot to check voltage after it turned red.
My Second K2 is already apart and will get XP-L HI V3 3A on same Maxtoch and driver will have resistor mods. Waiting on resistors. Would like to see what differences each have.
Very nice hotspot
I like the K2. Not a bad little light for the money!
Nice K2. Any idea how the indicator LEDs work?
came with a very low spacer, still has slight 4 pedal flower around the spot. I did manage to remove the chrome ring that showed outside the flower in the beam. Slight ream inside the reflector took off the flashing from plating and gave it a slight taper to the outside without reflection.
These were an Amazon deal couple weeks ago, $8.00ea prime.
I tried to follow traces and from what I can figure they go to resistors on the driver board. Real hard to follow as they pass under the switch board on angles.
Tom E. Has modded one when they were first out. He did sense resistors on it and kept the original driver because those lights are cool.
If I am able to trace them back, I would like to E-SW Fet the other, gutting driver except the SW and its components.
Suggestions for a 1S e-SW fet to piggyback in there?
Any of the e-switched MtnDD’s or Oshpark boards by various members.
Did some tweaking of the FET driver in my K2 triple. A while back I piggybacked a 15mm FET-only driver in the K2 and put in a triple XPL with CUTE 3 optic. Lately I was wanting the low to be lower, so I experimented with adding a gate resistor between the gate and pin 6 of the attiny13A. A resistance of 220 Ohms resulted in a low about equal to the moonlight mode in a Bistro FET+1 equipped light which I think is about 0.5 lumens. Before adding the resistor the lowest it could go was probably about 5 lumens.
Well,triple was my ultimate goal for the second K2. Didn’t mention it earlier as I needed to get the Fet functional first. I
Already have the spacers figured out with 2 xp32 sanded down and the x6 spacer to fit height wise.
@ EasyB
Did you keep the stock switch and lights for battery? Will search you for info…
I kept the switch but am not using the red/green switch lights for anything.
very nice mod on this nice light - I like it! I’m thinking about a triple Nichia mod on my X7 now.
Since then I piggyback'ed in an e-switch FET driver a while back, predecessor to Narsil, - a 13A. Hhmm - can't find pics of it though.
Thanks Ray, sent you PM and here is a link to where the X7 spacer came from.
Low-cost copper pills, spacers, optics, drop-ins. Custom parts from copper and aluminium for flaslights, lasers, sabers.
Good prices and pretty fast shipping from Russia.
Thanks Tom E.
Tried messing with this K2 driver earlier again today. It is beyond me to get it Fet with the battery indicators functional. Thought of powering driver just to keep the lights but every 4 presses it will kill the lights as the original driver powers off. Waste of current to just have that and a piggy backed Fet. Will try to use the LEDs as just the off time lighted SW button. Each LED on the K2 SW does have its own resistor and will utilize them or swap resistors into that space as needed for color choice.
Got the new Fet+1 saved in cart from MtnE with Standard Electronic Switch Firmware and LVP.
I did the K2 before Narsil, but most lights I have Narsil running in use an indicator LED, many of which are mounted with the switch, or by the switch. The K2 would be perfect for it. I think the Lumintop BLF SD10 is similar, and I'm using the switch LED with an air wired resistor:
