With a 10 amp driver, due to losses, no more than 8 amps will go to the diode, I think. Do you have a link to this driver? Can it be bought?
I would really recommend staying below 8A. The gain is output is completely unnoticeable, but the increased heat and shortened runtime is noticeable. Some SFT40s are known for the "black spot of death" issue, another reason to keep the current conservative. I'm running it around 6-7A in a C8 with ramping driver, and extremely happy with its performance. BTW a C8 takes 17mm driver not 20.
Maybe that ramping driver with a lower value sense resistor to boost the current. You can also do this on Convoy’s 5A drivers. I can’t remember the thread that gives the formula to work out the value resistor needed though
Will SFT40 be warmer than 6500K? I need 4500K or 5000K
FYI kaidomain has the 5000k. Edit: and it’s the DA tint bin, which has a good chance of being on or below the bbl!
Edit again: I was unable to order due to one of the required options for adding it to your cart being missing. I emailed them about it and now the entire listing is gone. Hopefully they’ll put it back soon.
Over in the Convoy thread, Simon recently teased a sample of the 3000k, so hopefully more soon!
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So the high CRI SST40 finally happened after what is it? 4 years? Even if it is the SFT40. I would not have mind it to have been the the SST40, with a shaved dome the duv would have been more perfect than the SFT40 will be. But I will be happy to use some of these 
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I quickly plotted the data shown in Convoys picture in the CIE1931 color space (credits goes also to Simon/Convoy!)
I am not sure if the data are 100 % correct, but if it is so, we can expect a tint with a little bit (but not annoying) yellow. Could be a great LED for thrower, at least if the tint is consistent with this type.
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Awesome! That doesn’t look as bad as I thought it might be. Very helpful to see it plotted like that, thanks.
I think this is a pretty big development. Hopefully this and the 5000k will be available soon!
I’m wondering if anyone put one of these in a Cometa and if it’s worth the effort. I would open up the plastic disk a little, of course.
If you are talking about the 3000K SFT40 then no, only Simon has the sample. If you are talking about the SFT40 in general then yes, there’s some SFT40 cometas/Z1 out there, and it’s a nice option, if you don’t mind the square hotspot when zoomed in.
Another option is the Yinding 5050 round LED, it will give you a little more intensity and the hotspot will be a perfect circle when zoomed in, and it will produce less heat than the SFT40.
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With danger of green tint, depending on the seller and batch.
Thanks guys! For my Cometa, I’m excited to use what I have at the moment which is a SFT40 from Simon. The Cometa doesn’t get much use despite it being awesome even with the 3B XP-L HI. I guess I’m trying to preserve that lens from accidents.
I also have an L2 with an Mtn Electronics FET+1, Crescendo driver with an SFT40 and it hasn’t had an issue being overdriven but I’ll be more careful with the batteries I use in it.
I have Convoy’s SST40 5000K, which is extremely green despite being DA tint bin. Hope to see colour tests of the SFT40 5000K soon.
I think I can make a test of the SFT 40 6500 K soon (with emitters bought by Mouser, not a ‘special bin’ like from KD)
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General-binned SFT40 is usually pretty ugly (and very cool), the 5000k tint bins are particularly interesting because of their scarcity.
Also it seems like warm and neutral high-cri SFT40 is going to be available later this year, it would be very interesting to see if they can stand up to high current or not.
I’ve had some pretty green 6500k, so worst case, all things being equal (green) I think I’d prefer the 5000k. I think minus green would work better on 5000k. Green, green, green- word of the day.
With Luminus emitters the only real solution I think. (From full emitter swap aside.)
The general-binned SFT40 like mine from Mouser are most likely used in flashlights. Don’t think that Wurkkos, Thrunite and co. will buy special color binned emitters from wholesale or directly from Luminus.
My SFT40 from Convoy/Simon has identical tint (at proportional drive levels) to the Osram CSLNM, which is excellent for a sub-70CRI emitter. It’s in 6500K; I’ve heard green things about the 5700K variant that was previous offered. I don’t feel so optimistic about the 5000K version, but a pleasant surprise is always welcome.
Do you know from what color binning this SFT40 is, or is it just luck to get a good tint in a Convoy pre-build light?