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 itās 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 doesnāt 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 changesā¦
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 didnāt 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, doesnāt 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 LH351Dāsā¦
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? Donāt see the point in cutting thatā¦
How about attaching some stiff plastic of the right thickness to the bottom of the boot? I guess that stiffening shouldnāt 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 lumensā¦ 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)
I have both the 18650 C8F and the 21700 C8F and have just tried various batteries.
I use a lux meter app on my phone and get 460 lux on the 21700 C8F using a Liitokala 4550Mah 21700 and also using a 30Q with the adapter. I then used a Samsung 30T 21700 battery and got 560 lux. On the 18650 C8F I get 510 lux using a 30Q.
So the 18650 C8F does outperform the 21700 unless I use Samsung 30Tās.
My 21700 sofirn c8f got only 7.22A used UT210E clamp meter and got 2,678 lumen. I use fully charge sofirn 21700 4000mah battery that come with the lights.
Finally have my 21700 C8 host working with the rubber boot installed. I had made a shim to be sure the boot wasnāt holding the button down, didnāt work. So today I used my Proxxon rotary and carefully reduced the length of the brass post coming up out of the switch. Put the boot in (shim still in place) no worky. VERY obvious space between the post and boot, but no good. Without the boot it works fine. So, I looked around on my table and found the black plastic tray some FETās came in. What they call the ātapeā. I cut the bottom out of one of the containers and placed this inside the boot, removed the shim, put the light togetherā¦ and it works! The rubber is soft enough that the switch depression rebounds and Anduril doesnāt recognize the press. So now with this thin bit of plastic in there it gives a positive enough click that Anduril sees it and the light works fine. Go figureā¦
I think 6-emitters would be the grail C8. I think LED4Power is coming out with a kit for the Sofirn 21700 C8F. Hopefully Kiriba-ru will make a copper spacer for this as good heat sinking is critical if we want to max the output.