Sofirn SP36, impressions of a sample

Well, how about placing some screws to fix the driver in the head? Would that be feasible? If glue is the only option, how about using glue that can be dissolved/broken easily like this hot-glue you can find in every DYI-store?

That is how it is done in the Q8 which is also made by Sofirn. Sofirn made the SP36 as a compact version of the Q8 so they are well aware of that solution, requiring milling the driver cavity in a non-round shape instead of simply turning it with a lathe, with added consequences for the spatial design of the driver circuitry. They decided not to do that, I guess it is a matter of cost.

I assume that they do not aim the SP36 at the modding crowd but at normal people, and perhaps rightly so, with the USB charging this is a very easy flashlight to handle, with still impressive performance. It may just sell well like it is.

Seems to be able to sustain low 5000 to upper/mid 4000 lumens in Turbo for 4 mins plus in a smaller/lighter host than the Q8. That’’s pretty efficient.

There are a few flashlights out there that have similar output at a similar size but this performance is surely at the upper limit for its size. But not the output sets this light apart, but the output combined with a decent reach, the beam is not all flood compared with lights with multiple leds/TIR’s. And it is the first in its class with 2 amp USB-C charging (no doubt more will follow though).
Hopefully what makes it most unique will be the price, I hope for under 40 dollar (but I have no idea btw, Sofirn has told me nothing about the price))

Any news or updates? I’m eager to find out more to see if I should stash some money away.

Not from me.

No updates yet. Postal tracking says my sample was delivered, but… it wasn’t.

This isn’t the first time my local delivery agent has done this sort of thing. Or the second time. Or even the tenth time. So I’ll see what I can do to track down the package. It’s probably either delivered to the wrong address or still sitting in his mail truck.

Okay, I have a SP36 now. My neighbor is a good person, and hand-delivered the package they received by accident. The label on the package is correct; my local delivery agent is just sloppy.

So. I have a SP36 sample. It’s a little banged up in ways which weren’t caused by shipping, but the important part is, the driver isn’t glued. It actually falls right out if I point the head upward without the body tube installed. So this should be a good host to use for development purposes.

I have Anduril on it, working pretty well. I haven’t tested the thermal regulation yet, but other functions appear to work.

The charger works too. If I connect it to a USB power bank, it charges at 1.5A. The flashlight still functions while this is happening, but the button’s charging LEDs override the driver’s normal indicator LED functions. That’s fine though. The light can actually be left in battcheck mode while charging, to get realtime progress information (ish; reported voltage is the charging level, not the cell’s resting level).

It can also run entirely off USB power, with no cells installed. It just makes the button LED behavior change; when it’s running at 5V it has no low mode for the button LEDs, and instead just goes smoothly from green to red as the main emitter power goes from moon to 350mA. And battcheck displays 4.2 to 4.4V in this mode.

It’s running the experimental SP36 build of Anduril I made a few weeks ago. I took some guesses about the light and the driver, compiled a version I thought might run on it, and … it works. So I mostly just need to make sure the calibration is correct, like for the voltage readings, thermal regulation, and the ramp shape. And then it should be good to go for production purposes.

Thanks TK. I’m looking forward to finding out the final details.

This may be redundant, but here’s a picture to show how the physical size compares against other related lights:

Emisar D4S (1x26650), Fireflies ROT66 (3x18650), Sofirn SP36 (3x18650), BLF Q8 (4x18650):

It aims to be a smaller Q8 with built-in charging over USB-C, and that is a good description of it.

As a side note, the SP36 button LEDs are in low mode here. On high mode, its button is the brightest of the bunch. Easily bright enough to use as a firefly mode or a low moon. However, I wouldn’t recommend leaving it on the high mode, due to the amount of power it uses. It’s almost as much as moon mode. I measured the following:

  • At 4.2V:
    • Moon mode: 1.96 mA
    • Button LED (high): 1.54 mA
    • Button LED (low): 0.08 mA
  • At 3.3V:
    • Moon mode: 1.32 mA
    • Button LED (high): 0.78 mA
    • Button LED (low): 0.05 mA

FWIW, the estimated runtimes with 3x3500 mAh cells are:

  • Moon mode: ~9 months
  • Button LED (high): ~13 months
  • Button LED (blinking): ~8 years
  • Button LED (low): ~18 years

So I’m setting the default to low during “off” mode, and blinking during lockout.

Thanks for the update Toykeeper. Going off to order VTC6s in preparation for this light.

I managed to let the magic smoke out already too. :slight_smile:

With the driver loose like this, something got shorted while putting the battery tube on… and it turned the red LED+ wire into ash. But that was the only part damaged, so it was easy to fix.

So, although it would be nice if the driver was screwed in like the Q8… without that, the driver glue is kind of necessary. Hopefully the next version can replace the glue with screws. Until then though, don’t expect to do any modding without doing like djozz did earlier in this thread. It looked like quite a bit of effort to get the driver out.

Thanks ToyKeeper for the work on the SP36. I think the SP36 is worth developing well because Sofirn already made a good start with designing it as it is, it has a nice size-performance ratio (better than the Q8 for me) and personally I like reflector beams better than TIR beams (and reflectors look a lot better too :slight_smile: ) . They could have made the design a bit more exciting (the ROT66 has that extra glamour) but because of the plain design it feels more like a working light to me, while I’m afraid to use my ROT66 in fear of scratching it :innocent: .

Now that I know how to do it, it is pretty straightforward, the main obstacle is that you need a pretty powerful solder iron (mine is 80W with a quality chisel-style tip) to attach the handle to the brass ring. My driver btw clamps well in place when pushed back into the head.

Btw, with a good mains USB charger plus short USB->USB-C cable (both Blitzwolf), the charging speed that I got was 1.95A, so the 2A charging that I was told by Barry it should have is met if the conditions are good.

I let the SP36 charger top off some cells. It runs at about 0.7 A when plugged into my USB hub, but that’s not surprising. Just slow, when divided between three cells. Anyway, it terminated right at 4.20V. I don’t know if this is normal or if I was just lucky to get one with an accurate chip, but it’s nice that it did exactly what it’s supposed to.

:person_facepalming:

Thanks a LOT guys! ANOTHER light I HAVE to have… more cells, always more cells…

*crosses fingers for NW tint option, minimal/no glue, decent price

So would 30Q or VTC6 button-top cells be good choices? Any others?

Samsung 25S will deliver the most power for the longest time, at a better price typically. There is a new 24S that might best it if it can be found. Either of these will outperform the Sony VTC5A which itself outperforms the 30Q or VTC6.

The GA and 30Q are likely candidates for a blending of power and run time, just saying.

The SP36 is now in their store.

New Sofirn BLF SP36 4*XPL2 6000LM