Sofirn C8F host. 21700 C8F Available

I thought about waiting for the Oslon Blacks but decided against it with the way this MCPCB is screwed to the reflector and such. So I sliced domes off Samsung LH351D 80 CRI 5000K emitters and built an Anduril driver for it. The Anduril firmware, to my experience, can be finicky about the switch in use and that’s the case here, actual working conditions are intermittent with a quick blink of the emitters the norm about 80% of the clicks. When it engages it ramps and works fine, but it’s not at all reliable. So these switches must have some peculiarities to em.

Beam profile looks really neat from these sliced Samsungs, works nicely. I’m using an iJoy 21700 3750mAh cell with one of Blue’s large springs cut off about 3 coils from the top. No bypass in it as yet. 20ga leads to the board with an SIR404DP FET. Left the spring bypassed tail switch section stock, again, for the moment.

Charging it up, will see if I can get it to work on the light box and get a read on it…

Oh yeah, the two white wires are the switch leads, the black illuminates a green emitter on the switch board and the red illuminates a red emitter, I didn’t try hooking either up as I really don’t care that much for an illuminated switch. (didn’t know where to put them on the Anduril driver anyway. lol [I used the D4S Anduril variant] )

I wonder if it uses a common ground or common positive? Did you happen to take a picture of the switch?

Could this be related to the other intermittent problem reported earlier in thread?

The LED’s on the switch seem to use a common ground, there are 4 wires… white, black, white, red. The 2 white at 1 and 3 position are the switch wires. I have tried a new switch, a second new switch, I tried a new switch directly on the wires with no board and that seemed to work so I removed the LED’s and resistors from the switch board and put the original switch back on (it has a longer post than mine) Seemed to work fine until I reassembled it and now the same issue.

I even moved the ground lead from the switch to the 7135 ground pad to ensure it’s solidly grounded. I don’t get it. I had Anduril act like this on my Meteor M43 and eventually replaced the rubber boot with a stiffer boot for a MagLight and it works fine, so I don’t know if this one is also because of the softer semi-transparent boot or what. Will check it again tomorrow and see where I can go with it.

It’s the boot with this switch. I tried several more things and ultimately, with the board installed and the retaining ring in place it works perfectly WITHOUT the boot. No glitches at all. Put the boot in and glitch city. So it would appear that the long post is being compressed by the shallow boot and not allowed to properly function. At least, in this particular light and with Anduril.

So maybe trimming the post with a razor blade 0.5mm-1mm would fix it?

It sounds like the software is not able to detect a switch click very well, is very finicky what the signal should be.
(my C8F 21700 host with mini-GT driver switches fine)

Interested

This isn’t a group buy. You can order right now.

http://s.aliexpress.com/IR77zau2

There is no post inside the rubber switch cover. Nothing to trim. The post on the switch itself is rather tall, rising up to within 1/32” or so of being flush with the surface of the retaining ring.

Edit: I should point out that if I use tweezers to touch the opposing legs of the switch I can operate the light without fail. I’ve run it up and down the ramp repeatedly, double clicked Turbo, engaged Candlelight and run through the blinky modes, adusting the Disco Strobe and Candlelight, again through the ramp up and down at will, by bypassing the switch mechanism itself it works perfectly, something about the clicky action of the switch, and several others including one too large to actually use in the light.

Hmmm, sounds strange. I wonder if this post can be sanded down? If plastic, maybe. If metal, I don’t know.

What do you think is the best way to give the cover a bit more room?

It’s a brass post on the switch but of course it’s loose and freely rotating in the metal housing of the switch body. Would be difficult to trim. The switches I have are much shorter, shouldn’t be a problem, but of the two of those I’ve tried on the board they just don’t like working with the boot.

Edit: I even covered the switch with Kapton tape with a small hole in the center for the post of the switch, thinking maybe the boot was causing problems through contact. Even tested the boot for continuity on my DMM, nothing there.

Edit II: About to try a shim, see if gaining a small bit of space makes a difference. The shim to be placed between the PCB and rubber boot…

I heard from someone that recieved 3 of the 21700 models and used a UT210E clamp meter and a short piece of copper wire as shunt.

1st unit: 8.0 amps < slightly less bright than C8F-18650
2nd unit: 9.3 amps = seems to be as bright (or maybe brighter?) than C8F
3rd unit: 7.6 amps < slightly less bright than C8F-18650

Can anyone tell me what the 18650 version drew? I think it was about 10A, right?

I would think the 21700 version should be drawing around 13A to 14A to get 1000 more lumen (3500lm), but we are way below that.

If anyone does happen to take their driver out, can you take some pictures of it and post it? I’d like to see what components are used.

So from the limited data we have would it seem to the more knowledgeable members that the 21700 version appears to be under-performing in general?

Just wondering if it could be a bad initial batch?

Yesterday I received my C8F 21700,
I measured only 2140 lumens, and only 6.07A at the tailcap.
Moreover when I step in turbo mode the brightness starts at about 1200 lumens and then slowly, in about 8/10 sec, it goes up to 2140 lumens, I do not think this is normal?

Maybe a stock of faulty drivers ??

Seems odd but even on a scratch built driver with a premium FET and 20 ga leads it seems to be under performing, even with Samsung emitters. Could it be the MCPCB itself? The pads on mine were pre-tinned but I added a small amount of solder paste before reflowing to be sure, got a wee bit of overflow so I feel pretty confident the emitters are solidly re-flowed on the board. I got 3100+ from my very first Sofirn triple C8 and that was even on their supplied cell. Only getting about that with this 21700 iJoy that a pair of them gave me 34A in my triple XHP-70.2 build.

So if it’s not the emitters, not the cell, not the wires and not the bypasses (I put a copper/bronze spring on the tail pcb with a 20ga bypass) then it doesn’t have a lot of places left to cause issue except the MCPCB itself. I should probably replace the hefty tail switch just to see what changes…

I used 18 AWG ledwires, Luxeon V leds, bypassed springs, a mini-GT driver and a Samsung 30T cell, and got 5200(3sec)4800(30sec) lumen. (until half of one Luxeon V stopped working, so a bit less now). That switch is about the best you can have in a flashlight, save for no switch at all.

Cutting the plastic washer out as a spacer didn’t help anything. With the spacer in place and the retaining ring on the light works fine, put the boot in and same glitch, mostly just a blink at the emitters and nothing.

This plastic washer was cut out of a credit card, I can feel the play between the boot and the switch post so I know the boot is not touching the post at rest. Still, doesn’t work. Works fine without the boot, just not with it.

The switch pcb is oblong, fitted into the switch compartment, and the switch itself is not in the center. So my plastic washer looks out of round but it is indeed true and matches the boot just about perfectly.

The above pic is with the light in lockout, holding the switch for momentary moon to show the sliced Samsung LH351D’s…

And now I ask, what is up with the design? Why did they not cut fins in the section above the switch? Only the opposite two sides have the new fins. Also, this one shows a slight shelf below the flat of the switch, was that a glitch or are they all like this? Don’t see the point in cutting that…

How about attaching some stiff plastic of the right thickness to the bottom of the boot? I guess that stiffening shouldn’t hurt. And extra thickness will make it touch the button at rest.

I get 11.76A at the tail with my Uni-T clamp meter, but only 3032 lumens out the front.

Edit: Remove the lens and it does 3236 lumens… the lens is costing 200 lumens straight up.

Edit II: Oh, and the amp reading is of course no tail cap, the lumens readings are light assembled with a large Omten switch on the PCB. (replaced the thicker stout looking factory switch)