According to the markings (2D030L) the old one is the NXP PSMN2R0-30YLD, which has a Rdson of about 2mOhm. That’s already really low. No way changing that to any other FET could gain 2 Amps, except the 2D030L
- is fake,
- is defect or
was soldered badly.
But I assume you found the real flaw with the retaining ring. And I lift my hat for that, because that would be a design flaw that’s very easy to overlook.
My fix would be to file down the lower part of the threading of the retaining ring in a 45° angle, so that enough threading is left but the ring can sit lower. That should give good contact.
I have a C8F v2 host I ordered right when they first became available. I haven’t managed to finish building a light with it, but I check the driver I plan to use with it for fit. The PCB is one of the Oshpark 2oz copper boards, which are really thin (0.8mm). The retaining ring clamps down nice and tight.
So, bad driver/ring fitment may be a problem for some lights, but not all of them.
Regarding the “filing down the lower part of the threading of the retaining ring” — may I request a photo or illustration of which part should be done? Sorry, I’m not really into modding and have not-so-good skills but would like to see if that can help the relatively low amps on the C8F 21700. Thank you.
What I mean is filing the threading of the retaining ring.
Underside, yes, but from the outside, to remove some threading so you can turn the ring a bit more.
Your picture, contactcr, shows filing down the inside of the retaining ring. You do that when the ring collides with parts on the spring side of the driver. This wouldn’t be the case here with the C8F.
Wouldn’t it be easier to just put a few solder blobs on the outside of the driver? I built mine with a 1.2mm thick 20mm FET+1 and had no issue but I guess YMMV. The ring is ridiculously thick so i’ll leave up the pic even though it isn’t what you meant.
Unfortunately I don’t have the 21700-C8F yet, so I can’t check myself.
I did this kind of filing several times with brass-pills (before the pill-less design took over) and it worked well to get the pill in deeper.
Of course you can do a comfy-style solder addon to the driver. Preferably the component side, as solder does not hold pressure well, especially not with a shearing force like from a retaining ring.
Btw, comfychair used a drill press to ‘mill’ these solder blobs flat. That was a classic.
Then there is the SP33.
I talked Sofirn again. They told me that talk with the engineer and will think about the songle led 21700 version. I said that make it like C8F so same double switch just change the front end to single led.
Like ZozzV6 said, the old SP33 was a single emitter 26650 light. I’m not sure why they changed it to xhp50.2 with boost driver. Maybe low sales? It might have been better to have 2 seperate models.
That good I like the 2 switch with forward click tail of 21700 C8F , hope for bigger head (55-60 mm.) with XHP35 for better throw and please make the light switch to stay on as locator .
