Since you asked, the Aspire 18350 cell is quite a bit better, especially for this high drain application. Not too sure where to buy them though. They have been slowly disappearing at all online stores.
See HKJ’s tests for these two at 5A and 10A:
Maybe Vapcell 18350 1100mah from liionwholesale as a runner up?
The Efest IMR18350 700mAh are also a bit better than the Windyfire (at least at higher Amps), despite not better than the Aspire 110mAh/ Keeppower 1200mAh (and eventually the Vapcell) 
EDIT: Sorry: nice work with this I will take a look on your other thread, to see if this driver suits my “needs” for a blast of light :smiling_imp:
The Vapcell 18350 1100mAh is supposed to be the same cell as the Asprire 18350 cell.
Nice build with a great driver!
Thanks everyone very much for the kind comments!
Yes the Nanjg spring looks more appropriate to the driver, but as you can guess, the total current draw from the battery is pretty high even with my output turned down to 4.2A. Current draw depends on the battery (how much the voltage drops as current is being drawn), as well as contact resistances etc. I measured just about 8A or so on the bench but it might be a little different inside the flashlight itself due to contact resistances etc. These play a big deal since even just 50mR of extra resistance somewhere = 0.4V drop at 8A - very significant. As a result, I decided to go for as big a contact I can with the spring, so I chose this bronze spring which has a large contact patch to the battery-end.
Thanks everyone for the good suggestions for 18350 cells. I'll pick some of them up and they should provide better performance than the WindyFire!
Awesome job!
Where’s the group-buy for those drivers? :heart_eyes:
No 'group buy' just yet, but if the response is good I think we can look into getting a batch of them assembled and made ^_^. Check out the GXB172 thread for more information on the driver: https://budgetlightforum.com/t/-/50015. Thanks for your comments!
Made by the same factory in China. Yongdeli
Looks great! The candle mode is really cool!
Thanks! It's a really simple flicker algorithm but I have some ideas to make it more realistic. I suppose the first step is to try it out in a <3000K flashlight though because it looks a little odd now coming from a 5700K emitter. I tested it yesterday night with a yellow plastic bottle on top of it in a dark room, and it was surprisingly pleasant, would be fun in outdoor camping I think. I'm also pretty sure I've seen some mention of candle flicker and other modes in some custom firmwares, like in the BLF lantern, or some of the modes in Toykeeper's firmwares.
Many thanks for sharing this excellent build! In line with true BLF spirit, this is a good inspiration. really cool build.
I like the candle flicker mode, was wondering why almost no other light has it.
Awesome job man! Congrats!
Hey all,
Quick update! I've further improved the performance of this build - again this build was designed to be a primary test vessel for my GXB172 50W Single Cell Boost Driver.
First, I swapped out the optics. Originally this used an Orange-Peel reflector. However, for those who are familiar with Nichia 144 LEDs, you may know that the phosphor on the die appears to be fairly un-uniform. As a result, the center of the beam is typically much yellow then the outside. In order to fix this, I replaced the OP reflector with a TIR 45-degree honeycomb optic with suggestion from Texas_Ace. Thanks for the tip!
The result is a much more uniform beam and a very very pleasing tint! This really transformed the output of the light! The only downside is a slight drop in OTF lumens, but with a much better quality flood beam.
Details for different TIR optics here: https://budgetlightforum.com/t/-/26270
Next, I also improved the tail-switch by adding in:
The tailcap light has the added feature of changing colours (in this case from Blue to Red) when battery voltage drops below 3V, and turns off completely when battery voltage drops below ~2.7V.
For more information about my GFS16 tailcap system, please see this thread: https://budgetlightforum.com/t/-/50404
Still working on the GXB172 but so far it's seen some improvements in both thermal regulation and overall features :)
As usual, more to come soon!
Oh wow! Nice job on this light! I’ve been following your driver threads and your new tail-switch PCB thread. Plenty of us are waiting for you to release the drivers so we can have them in our lights!
You just made something very close to an ideal flashlight for me. If I had it in 4500-5000K, I might think I had died and gone to heaven. Anxiously awaiting commercial release of your parts.
And I can’t help but drool over the possibility of a 21700 light almost exactly like this.
I am going to be ordering some XHP50.2 4500k 90CRI LED’s in the near future, I expect about 6-8 weeks for them to arrive.
I might order some extras to sell if there is interest. One of these combined with this driver IS my ideal EDC until something better comes along.
I’ve never seen a high CRI Cree LED, but I would be willing to try one. Unfortunately, I don’t have the tools to reflow, so if you aren’t planning to sell that service, also, I’ll probably go with a Nichia 144 and mcpcb from virence.com.
Yeah, if I sold them I could reflow them as well.
I am guessing I will order a few extras. The tests I have done with the 90CRI XHP50.2 so far have been fantastic. Great rosy tint and great output (around 4000 lumens in my testing IIRC). It is what I plan to convert a lot of my lights to including my EDC.
Huh really? I thought that even at high CRI levels, the tint of second gen XHP 50 and XHP 70 is still quite bad.
I’d be interested in a couple depending on the price. I’ve only seen the 5700 90cri leds. How is the tint shift on the 4500k?
Yes!!
I keep harping on this, but with S2+es, the quickest’n’easiest way to get rid of the usual fried-egg beam is to swap in a TIR.
Makes a so-so to yecch beam flat-out beautiful!