I finally received all the parts to put in my UF-1504:
-XM-L2 U4 1C (purchased it dedomed as mine always seem to turn green when using gasoline)
–17mm FET drive with guppydrv
-Efest Purple 4200mAh 26650
The big brass pill made everything go together quickly and with little effort. I was actually somewhat proud of my clean work. And, I think the retaining ring is plastic which means I didn’t have to worry about anything shorting out. To test things out I used the sleeve and a protected Panasonic 18650. Woohoo! Looked like high and low working just fine. So, in goes the purple Efest, turn it on, it flickers a few times and that was it. Nothing. I tried the Panasonic again and still nothing. Checked all connections, tailcap, and all looked good. I also inspected the led under a lens, but it looked entirely intact with no broken wires.
I ended up pulling the led and soldering to a Qlite, and nothing, so it looks like the led is fried. Also, I kept the stock leads on the driver, which I think are 22awg. I can’t imagine this would have been enough to blow the led, but it looks like it did.
Didn’t reflow it. Came on noctigon. Hmmm…I wonder if I try heating it up to reflow if that might fix any connection issues. I’ll look at it again under a lens, but all the tiny wires looked intact and the emitter itself had no dark or black dots…I know what that looks like 8)
Upon closer inspection you are correct. However, I don’t believe this shorted it out. I had pressed my solder points with a small flathead to keep them as low as possible. Plus with the reflector spacer and the way the ring is shaped I think there was room to spare.
I literally just built a light exactly like this (although I solder the MCPCB to the pill, OP didn’t specify what he did) without the retaining ring, and using the Efest purple 26650 3500mAh battery it doesn’t have a problem. I ran it for 3-4 minutes on high and it was barely warm.
Good to know this setup should work, and thanks for the input. This isn’t the first, nor will it be my last screwup. When I find the emitter I like I will most likely solder it as well.
You might be able to fix the driver, maybe just the FET is blown? Usually you can smell something like the guts leaking out of the FET? You can get them from RMM, I smoke one every now and then. As far as the LED
Test the LED directly with a moderate cell, such as an almost-drained 18650. It should light up. Look closely at the bond wires, and see if they are intact. You may need a loupe for this.
The newer Cree LED’s, higher bins in particular, are prone to burning out even at moderate currents (4-6A).
I builded 7 of those lights, several more to come
U3- V6-S3 bin all, same driver, abs the same battery
The body is quite solid and it can hold the light in a DD mode till the battery drained, tested every one of those leds this way
My best bet is that the emitter died cause of the dedoming, maybe it had a damaged the core`s wiring( sometimes they look intact)
Or maybe those U4 bins cant hold that amperage, havent realy tested any
Try the driver out too
The only spare led I had that I was willing to use in this host was a dedomed XP-E2. Soldered it in and it fard right up. So, the good news is that the driver is good…just wasn’t the U4’s day I suppose. I’m getting just under 2.5 at the tail for the XP-E2 which is probably all she can take, but the result is just blah. Still debating on whether to get another U4 or try an XP-G2 this time around. Appreciate all the replies.
CREE XM-L2 U4 1C LED (Dedomed) on Noctigon 20mm MCPCB FET + 7135 Driver - 17mm - MTN-17DDm FET Firmware: Standard w/ Memory, Turbo Timer: 90 SecondsBraided spring bypass on driver spring and on tailcap spring.The turbo timer will step down to level 5 after 90 seconds as a safety feature due to heat, but you can go back to turbo with a tap on the switch after a few seconds.