Haha, it's the luck of the draw. It looks so good that I don't want to use it and just keep it hidden behind my glass doors in my light cabinet.
Can you elaborate on the dead tips? I’m really not good with soldering and don’t know much about it. I’ve been using a Weller brand solder station at work and have to crank it to 800 or 850 to even melt the solder on the MCPCB. Does that mean the tip is bad? I thought they were just pieces of metal.
The tips are plated and repeated use and high temps wear it out. You can treat it like your grill. Store it dirty and clean before you use it. If your tip doesnt get nice and shiny after wiping off fresh solder its probably not working as well as it should be. They wear out and are meant to be used and replaced. 850 is pretty high could probably do less heat on a nice newer chisel tip
Leadfree will wreck solding tips in a hurry. Also running over 800F and using a wet sponge instead of the brillo pads to clean it will wreck tips.
I prefer the Hakko irons with the heating element integrated into the tip but there are lots of chinese knockoffs out there now that are just as good or better and definitely much MUCH cheaper than the Hakkos.
I use an analog Hakko 888. If a tip gets slow to react I file it clean and re-tin, keep on going. Experts say this doesn’t work, yet here I am still using my original chisel tip. What do I know….
For soldering cells/large ground planes, I use this massive beast:
https://www.amazon.com/Weller-SP80NUS-80-Watts-Soldering-Iron/dp/B00B3SG796/
It’s a bit overkill as you can tell, but it does allow me to solder lithium ion cells super quickly.
Most of the time, I get 2-2,5 seconds, but sometimes when I’m feeling particularly good, I can get under 2 seconds 
I sanded one of my hakko tips and it’s basically crap now. Maybe yours is from a different era but YMMV with that advice.
Well, I did say the experts disagree with my methods. I just didn’t know that before I started doing it. The things you don’t know, ya know? 
I don’t know what that coating is on the tips but I’d guess it is “expensive” and maybe old tips were solid, whatever that is…
All I know for certain is that lead-free leaches that stuff off the tip, and the wet sponges cause thermal shock which cracks the tip.
I have a Hakko FM-204 that I got a VERY good deal on when I was looking for a FX-951. Before that, I had used loads of Wellers including some of the stupid expensive models.
Where I work, one guy got a block of “sal-amoniac” or something like that, and it seems to refurbish, the special coating on tips to some extent.
I use this… https://www.radioshack.com/products/radioshack-tip-tinner-and-cleaner-0-5-ozevery once in awhile to deep clean my tips then re-tin with solder 4yrs and still my tips are like new… Hakko FX-888D and Hakko tips…
That Radio Shack tip cleaner is simply Ammonium Phosphate and Tin, essentially Solder with Sal Ammoniac. One of the ways to use the block of Sal Ammoniac that prolongs the use of the tips is to melt a solder blob onto the block and then push it around with the hot tip. This is a less agressive way to keep the tip cleaned and tinned. The hot ball of solder picks up some of the ammonia salt and transfers it to the tip without actually putting the tip directly on the block. Supposed to be better for long tip life.
I’ve found that using leaded solder, the tips just seem to last forever so long as you don’t use those sponges. I have a Weller WES51 that I’ve never replaced the tips on. I’ve bought a few different ones to use with it, but never replaced any of them.
M’k well… it simply works, a couple swipes, tip is beautifully clean re-tin and done 
I've looked at those microscopic sized aux leds often and can't imagine how you would replace them. Based on everything you have done, I know you can do it, just don't know "how" you do it. My hand is fairly steady, but nowhere near enough to swap something that tiny.
recap on my twisty e07…
its not direct drive…
but somewhat in low output (not moonlight)
the ramping is working… but cannot go low
double click to turbo is working… batt check etc
cannot completly turn off
btw… im testing it without the aux board soldered yet…
Neal or Jacky? So it’s official now, I guess? And still no statement from Fireflies here other than per email? Would be interested in the original wording of what he said.
Neal gets his lights directly from fireflies, not sure where his batteries are coming from.
I think he discovered himself that the cells are not genuine.
I think he acquired an internal resistance tester after seeing the reports, and saw that some of his 40Ts weren’t 40Ts.
Jacky wouldn’t be selling fake cells voluntarily.
This light has a triple channel driver, the lowest modes are on a single 7135 chip… that chip probably got fried.
When Ham’r messed up on me after I shorted a test cell it wouldn’t turn off either, ramped and did Turbo but only in high levels of the ramp where pwm is applied to the MOSFET. Had to break contact with the cells to turn it off. After replacing the 7135 chip (only had one in the low channel, FET+1) it worked perfectly once more.