Sofirn SC31 PRO, New Anduril Flashlight

Thanks! I was thinking of trying to push a SOIC8 clip through the switch hole to reach the MCU as a backup plan to avoid soldering. I’ll probably end up swapping the emitter anyway… but it would be useful for those who just want to update/change Anduril.

To be able to pull the board down to reach the MCU, would you need to do the following?

  • Remove the bezel with some straps, a vice and heat
  • Desolder the 24awg wires from the PCB with the LED
  • Pull the board down by pulling on the spring

This is close to what I did, but:

  • removed the bezel by clamping the head in a vise, cushioned by pine boards (no damage)
  • either I used my sticky blue gloves, or used a strap wrench - seem to recall it came off fairly easy, no heat used (sorry, I mod a lot of lights and lose track of details, and had no notes)
  • de-soldered the LED wires form the MCPCB
  • using a solder pick, pocked it thru the Batt+ LED wire hole in the shelf, try to feel I'm not sitting on a chip, applied steady pressure til breaking the glue bond holding the driver in
  • then pulled the driver down by the spring

You really can't fit the clip thru the switch hole, plus the MCU isn't right there to access.

Finished my mod today:

  • replaced the 24 AWG with longer 22 AWG wires (so I can re-flash without de-soldering)
  • replaced the stock 6500K SST-40LED and 17 mm MCPCB at 1.5 mm thickness, with a 5000K SST-40 on a 16 mm Noctigon (slightly thicker at ~1.6 mm)
  • sanded the shelf MCPCB contact surface out to 2500 GRIT, applied fresh MX-4
  • tossed the set screw used to keep the stock MCPCB from turning (Noctigon didn't have the cutout to support it)
  • re-flashed with Anduril2
  • 22 AWG bypasses on the tail and driver spring

It now measured 8.1 amps on a 35E cell at 4.20V. Max lumens and throw is about the same as the stock light did on a VTC5D cell. For the heck of it, tried a 25S at 4.17V and read 9.0 amps, only about 75 lumens higher.

The lumens on the 35E initially is 2310 (Tom E), 2040 calibrated. It drops pretty quick. It really is more amps and heat then the SC31 Pro can handle.

The 5000K tint is an improvement, least from what I recall...

Thanks for the detailed write-up!

Would it be fair to say that the SC31 Pro isn’t easy to reflash with a newer version of Anduril unless you remove the bezel with force and desolder some wires to get access to the MCU?

@Sofirn: Please add pogo pads near the spring :innocent: :weary:

Yep! At least though you don't have to replace the driver and lose charging, like I've done on many other lights .

Totally agree - if Sofirn goes with an open source driver, they really should make the effort to make it flash-able, now that we have a method to do so with the pogo pins.

I swapped the MCPCB out with one from an SP40 (i think), and a 219C 4000K. But I don’t think I’ll go harder; I was getting a little over 5A but that’s enough for me on that.

Are there some good 4000K emitter alternatives to the SST40 5000K for the SC31 Pro? :student:

It’s a nice flashlight. I wish it were warmer than 5000K.

Well, could use an XM-L2 maybe, but I'd go with a 351D, tint of your choice, and diamond in the 5050 centering piece -- I've done this a few times before, and the 3535 LED comes out centered. Basically as you tighten down the reflector, the 3535 LED turns in the 5050 centering piece til it settles at 45 degree angles - usually hangs up there, dead on at 45 degrees so comes out perfectly centered.

Is this something you did? Dunno how that is done, but I haven't played with pogo pins much.

Luxeon V 4000K is a very nice and overlooked high-power 3V led. IMO way nicer than the SST-40. 4040 size though.

Same for me, so I wrote a PM to Barry who answered: “I don’t know there is a HCRI version of SST40, if it’s available, I will try to use it.

Hence my newb question: as far as I understand, in order to swap a LED with another, both should have the same voltage (I believe some require 12V) and the same footprint, am I correct or should something else be taken into account? Is there a "compatibility table" somewhere, classifying the current LED models according to these two criteria?

+1

Another newb question: if wired properly, could the USB-C port be used to flash the MCU? That would be the easiest solution, no need to disassemble the light at all.

5050 3V is almost bereft of decent emitters (especially w regards to high CRI). XML2 in <3000k is about it. Hence me ripping it out and popping a 3535 mcpcb in, but needed a new centering ring, 7mm (but slightly loose). Either way, much nicer now,

Similar Forward Voltage is required.

I think you can try to put a slightly smaller LED on a slightly larger pad (e.g. 3030 on 3535). TIR optic and reflector might need to be considered case by case…

Success! My SC31 Pro now runs Anduril 2. Flashed without removing the driver!

It was surprisingly easy. First I removed the switch bezel, the silicone switch cover and pulled out the switch PCB to have a look at the driver. The wires are long enough. The MCU is located right in the middle of the big hole – how awesome!

So I made a little jig to update the firmware. A 4-pin pogo-pin adapter to contact pin 5-8 (MOSI, MISO, SCK and VCC). Without a matching PCB (0.05” pitch) this was the hardest part. My final solution was to use a ribbon cable (comes in 0.05” pitch), crimping the pogo pins onto the ends and glue everything to a piece of plastic. After the glue has dried, I covered everything in hotglue and heat shrink tube (that’s my usual way of making custom adapters). RST was hooked right into the leg and GND was the easiest: Just clamp it between the head and the battery tube.

Now that everything was in place I connected the programmer and my laptop, built the latest version of Anduril 2 with the SP36 config (which is used by Sofirn for all of their Anduril flashlights) and hit return.

Everything went well, so I could remove all wires and put the switch back together. Done, Anduril 2 update on the SC31 without removing the driver.

WELL MR LAH DEE DAH

Nice! That's pretty cool!

Btw it should also work with the usual ProgKey that fits Lexel’s drivers, Emisar etc. Four pins on the legs, the rest on the MCU. My first attempt was an all-in-one adapter with six pins, but I was not able to print such fine details with my 3D printer.

A little bit of silicone grease helps to screw on the switch bezel without rotating the switch cover and switch PCB.

Very nice.

I just got my 18350 tube for my Pro today. Using a Convoy S2+ clip, it’s now wonderfully sized and carried deep in my pocket. Because the light doesn’t draw a ton of amps, it still puts out its full power too. It will be a while before something replaces this light as my EDC.

I heard of him. Born in China. He lives down under now?

Nah, he’s married to Queen Lah Tee Fah…