I put SST-20 4000K LEDs in an E2L triple (again). Using a FET+N+1 from Lexel with Bistro HD.
This time they seem to be surviving. The last SST-20ās turned yellow on me after testing a high drain battery on turbo. Maybe my reflow was bad, guess time will tell.
Does about 2,400lm at 0s with VTC6
I also added a clear switch boot and drilled a tiny hole in it for an ice blue trit. Thanks to Dale for showing me this. Just enough glow to see it in a dark room but not enough to bother you and it doesnāt drain your battery.
I kind of like how pointy the beam looks in my triple with these LEDs. What do you think? Between these and the LH351D you really have both extremes of beam shape covered.
Does emitter swapping count? First I bought a preflowed mcpcb with a 4000k Nichia on it for my H03, did a simple mcpcb swap. Then last night I did my first ever emitter reflowing, I swapped that 4000k Nichia for a 4000k LH351D that pairs better with the TA driver I put in that same light. It was a success!
Also, that TA driver, i got it from Lexel, prebuilt. But I also got some bare boards and all the little bits that go on it, and I built two of those out a couple nights ago, my first time! And they seem to work fine. I havenāt tested them fully in a light, but I flashed anduril and ran through the modes with a test led and it all seemed fine.
I love this place so much! Thank you all for your help. You guys are awesome.
Been away for awhile and this thread has gone mad. To many mods to comment on but lots of terrific work going on. Well done guys and keep posting your mods up.
Tbh Iām a bit worried to run it on full turbo. The heat generation feels about the same as the Nichias, which is pretty extreme. I donāt want to fry anything (yet). I might start to take measurements with 4.1V and go up from there.
The beam is still very smooth, no defined hotspot. Not really my type of beam, but better than the even less focused 219Cs.
Iāve run my D4 first gen (not tamed) with 4 SST20 on Turbo until the temperature protection kicks in, repeatedly so I couldnāt hold the light anymoreā¦
The LEDs seem to be fine, well they didnāt tint shifted or desoldered so I guess theyāre okay
As long as your reflow is good you should be fine (especially with something like a VTC6/30Q). My triple has less output but higher amps per emitter I would guess and it seems to be doing fine on the 2nd try.
If you are using the smooth narrow optic that is probably as tight as it will ever be with a multi emitter TIR. Maybe try a C8F or something if you want more hotspot. The LEDs definitely are capable of making a nice tight beam though.
I have LH351D, 219C, XP-L HI and SST-20 all in triple carclo optics and you can see the difference in beam shape pretty noticeably between them. I listed in order of most floody to least.
I can only measure Lux though. But when I know the current I can probably estimate the OTF lumens pretty well with an output chart.
Edit: 4.16V VTC5D gives 18.7A. 10 seconds until its too hot to touch. Thatās 4.7A and 933lumen per emitter according to maukkaās output chart. Letās say 80% leave the front, so roughly 3000 Lumen OTF.
Itās such a nice 4000K tint. :+1:
Replaced the tailcap with dual Beryllium Copper springs for maximum conductivity and brightness.
On the stock XP-L HDs, with an AR lens and brass screws, along with the new spring arrays, that got me 6764 lumens at 30 seconds. The lumen number compared to others might be a bit higher since Iām using a more efficient lens(6500 without the AR lens), but Iām still extremely impressed, considering I didnāt do a spring bypass.
Now for the real star of the show: the 4000k 90CRI LH351D. This LED almost has beautiful color reproduction, and is more efficient than most other 3V 3535 HiCRI LEDs, meaning not as much brightness is sacrificed in exchange for the higher CRI.
The tint is also better than the 219C, with less green than it. Itās also quite a bit floodier, meaning it gets a more balanced beam.
All in all, this resulted in an amazing beam, and a renewed interest in the light. I now use it absolutely everyday, and I now use it as a soft light for photography and night hunting, and as my big EDC
Parting shot
I have to say. I really like this mod, as it made the Q8 my new favorite light
@contactcr, I mentionned that this was for the stock XP-L HDs with all the mods possible in the light, which include the new springs, AR lens and brass screws. Iām probably getting a nice boost just with the AR lens itself, about +/- 200 lumens.
The 4000k LH351Ds 90CRI are less efficient than the XP-L HDs, and they get around the stock numbers, so around 5100 lumens, which was to be expected. The light is getting much hotter than stock though at similar power levels due to the much lower VF at the same current, meaning they pull quite a bit more current than XPLs. They are quite close to their max brightness. I wouldnāt do any other mods, so no fancy 16AWG power wires, no wire bypass, as the difference would still be minimal, no FET change, etc.
LH351D: 3,53V at 5A
XP-L HD : 3,81V at 5A
Consequently, even lower modes get hotter.
Edit: Iām always testing with Samsung 30Qs at 4,19V.
Unless you have the privilege to work with top-of-the-bill instruments, that will have to be calibrated in a regular interval, all measuring is pretty much a relative thing. If Blue SwordM says that a certain mod will improve things by 5%, I will believe him. If djozz says the same thing, I believe him too. What I donāt believe, is that both of them get identical results when they unbox their lights for the first time. The difference may be in the lights itself, it may be the measuring equipment they use. And the batteries, of course.
If you or me perform the same mod, we will have an identical outcome. As a percentage. Not in the actual readings of the meter, before or after the mod.
@BlueSwordM that explains it much more clearly i missed the XPL
HD part since the rest was about the Samsung LEDs. I have done this exact mod and got similar results as you did.
