I went back and looked at TK’s review. I saw it before but I didn’t realize it was two boards stacked on top of each other. Cool.
That doesn’t make it any easier to change out the main LEDs though. It’s not that bad but it’s certainly a delicate procedure getting the wires back in place and neatly soldered. You wont be just mashing the iron on a huge open space where the only two hookup wires go like the FW3A. 
Have the modes/lumens/runtimes for the SST-20’s been posted anywhere? I have only been able to find info on the XPL HI’s:
Moonlight ~0.2 lumens (~74 days)
1 x 7135 Max: ~130 lumens (10 hours)
8 x 7135 Max: ~900 lumens (1.25 hours)
Max FET: ~2800 lumens (**10 second stepdown due to heat)
Wondering what the specs are for SST-20.
Everything except FET modes will be nearly identical as the 7135 modes are current regulated, although it will stay regulated for longer due to the lower forward voltage so runtimes will be slightly shorter. FET modes will be shorter for the SST due to more heat and lower forward voltage of the LED (=>more current)
Here’s Bob’s numbers for SST-20:
https://www.reddit.com/r/flashlight/comments/c6vfe5/review_lumintop_fw3a_sst20_with_colour/
Great info there, exactly what I was looking for. Thanks!
Your not taking into consideration the output of the SST-20. When compared to the xpl-hi, the SST-20 has maybe 30% less output at the same current. So 1 x 7135 is still a regulated 350 milliamp, but the output is lower. I don’t know if it’s lower forward current plays a factor in the regulated modes, but it definitely does when using the FET.
The effect of forward voltage on a current limited PWM signal is making my head hurt. :disappointed: Maybe someone here can explain it.
I’ve been waiting to pull the trigger on an FW3A purchase - specifically waiting for various issues (hardware and software) to stabilize… now?… now?… seems close - am I wrong?…
What issues do you mean?
The software is the same, no problems there. Maybe in a couple months they will update it to include the reset function (not really necessary, IMO)
Hardware wise the factory switched the optic. It’s still a good optic, but if you want the Carclo you can order from Neal. They seem to make small changes to the button design, some better, some worse so it’s a toss up there.
I see no reason to wait, unless it’s for a colored one or a metal version that’s not out yet.
It is reportedly hard to solder all the wires to the two different boards to reinstall everything after you replace the emitters, though.
If I remember right, even DB Custom commented on it being a challenge, and he’s got quite a bit of experience modifying lights.
Plenty of room, just have to have your wires set-up with the right length and in the correct position (s) to reach the pads.
If you can reflow 4 emitters at once you can solder 4 extra wires.
Is it harder than a basic light with one single emitter on a nice, open 20mm star? Sure.
Impossible? Absolutely not. My statement above stands, don’t let a few extra wires stop you if you’re otherwise confident in your reflow abilities man, this is BLF, we mod things to out liking around here!
principally hardware, like the tail-end nub size, and switch ‘feel’ have recently been mentioned - and yes the optic… also, firmware can always change… minor stuff… mfg’d stuff has a life progression, usually for the better…
I’ve heard that the hardware has had a revision in the most recent batch. Specifically it seems to have a retaining ring in the tail, and the nub has been replaced with a wider one. And a batch or two ago, they also switched to brass for the head retaining ring. These things should make it a bit more reliable.
Firmware also has been getting updated periodically. I think they have a version with factory reset now, but I’m not sure how long it’ll be before it’s actually shipped to anyone.
hey- thx for the heads up on that, tk… I’m just a noob trying to pay attention here… does/will that firmware origin with you? - and reside (someday) in your reposit?… oh boy - another collectable micro-stabbing com device for my box-o-jtag junk collection… btw, (off topic) the funniest thing I read in the last ten years was on your pat site - re: expensive flatulence creation thru the magic of control voltage devices - hilarious… thx for that too… later…
Good news on these updates. It’s always good to see improvement. Hopefully the latest firmware will make it into the purple one I just ordered . Can’t wait to get it and check it out.
Did you limit the FET on your FW3A 219B? I have the same LED’s on the way for my current FW3A running 219C’s from Kaidomain. It draws 9.1A on turbo with a fresh Samsung 35E cells. It should be safe for the odd turbo blast with the higher Vf 219B’s, right?
I am running TK’s firmware version for the 219’s. That should be the version you have installed already. It is great for those leds, I have not had problems with short bursts of turbo, no blueness after 20 seconds, but she does get hot! If you are using a glow gasket, I would suggest seating it as high up into the optic as possible and then a drop of glue to hold it off of the mcpcb. My worry was cooking the leds with the glow gasket. I have not taken the time to figure out how to get a current reading from all the contact points yet. I am going to put it on a bench supply and see what the head alone draws, but I can’t get much more than 10 amps out of my supply.
So, I have 3 of these now. Once change that I have noticed thru the various manufacturing times is a change in the tail switch, and I do not like it! My very early one has a very tactile feel, activation takes a good click. The next one purchased has a softer switch and the latest is even softer. I have requested a replacement board for the last one, I think it has a problem in the little switch as it activated setting on the file cabinet without being touched. Yes, I did switch nubs and covers and it still happens. With the board in hand the switch is way to soft. I do not have any of the new ones with the retaining ring in the tail. And my oldest does not have the brass ring in the head, the existing ring is tough to remove and reinstall without it trying to cross thread.
All in all, the best BLF/TLF light to come along, IMHO.
I doubt it’s that version that limits the FET. It’s one of the 1st models that I ordered with XP-L HI 7A’s and they are in my FW3C now. I had Kaidomain 4000K 219C’s from a previous triple build that I’m running in my FW3A now. On a 30Q it gladly draws 14A on turbo. After continuous testing I couldn’t get the light to draw more than 9.1A with the 35E cells. That’s just over 3A per emitter, and that’s about as hard as I would push the 219B’s. Maybe I should just attempt to flash it if I burn one of the LED’s.