so i took my solarforce p60 driver apart and find what looks like a part that has snapped and another part that is burnt. I am wondering if i could salvage this driver or should i just buy a new one?
sorry picture is a little fuzzy, took it with my tablet.
Maybe a picture with focus on the burned parts and maybe you can resize the picture before uploading(nice floor 
)
I guess it was a resistor…
What caused this damage?
Something else caused the resistors to pop, just replacing them won't fix the original fault. I vote for 'dead'.
Kitchen counter.
LOL
Yea I will get a better picture uploaded tomorrow
It’s toast…on the kitchen counter.
Thanks guys but is is my office desk.
updated image guys
looks like the resistor exploded
try to replace it(maybe bothe of them)
Yeah, looks the solder melted during that and allowed the left part to stay vertical.
kinda what i figured. I will try to resolder a couple more resisters but i am not putting my hope too high.
Both resistors are in parallel, both in the main current path from LED- to ground. The one on the left failed first and merely burned out, when all the current only had the one path through the resistor on the right that one failed in a more spectacular fashion.
None of this matters a bit unless you already know what caused the over-current situation in the first place. Resistors don't wear out, they don't fail unless some other condition causes them to.
I think it more of me being stupid and believing solarforce when they said that it could handle 2 18650 batteries.
I have 3 SF P60 dropins and an M3, they all had the drivers fail. They should stick to making hosts.
Meh, it looks like it could/might work on 2x18650 to me. This driver appears to be using the QX9920 buck controller with no voltage regulator to feed it, which isn’t actually what the datasheet says to do. I assume that there are no components on the bottom of the driver? If they are feeding the controller battery voltage directly then that could be the problem, OTOH maybe it’s fine to exceed that rating with this controller. I assume you were using normal 4.2v 18650’s? [Which SF dropin is this out of? If you have the parts to do a zener mod we can easily ensure that it will work with 2s in the future.]
If the stock driver was set for 2A I think the sense resistors should both have been about R25 (0.25 Ohms, same as R250). Since Fasttech doesn’t stock those I’d consider getting R27 instead. That should yield about 1.8A. Another option would be a pair of R22 for about 2.3A. You could do one of each, but that’s getting into a lot of money to repair a single-mode driver with no LVP and which apparently doesn’t function to spec.
thanks guys
I disassembled a similar Solarforce driver this evening.
I did not realize from your earlier pictures that this is a two sided board. As soon as I realized it was a two sided board I assumed that I would find a Zener on the back, as per the application circuit in the QX9920 datasheet. I was surprised to find that there is only a reverse voltage protection diode and the Schottky diode for the buck circuit. I will investigate this driver further soon in a new thread and put a link here. (Probably SF just decided that the QX9920 could take 8-9v without failure and that’s the whole story. Not necessarily a problem. In fact, given the limited availability of “real” datasheets for QXMD chips, it’s entirely possible that the datasheet I’m referring to is bogus.)
I’d say that there’s a fair chance of it just being a crap sense resistor; as someone else mentioned once on failed the other was bound to fail.
On my 2yr old driver of the same design, the stock sense resistors are R220 and R240, one of each. If I was trying to repair the driver on the cheap I’d just replace both of them with R22 from FT, that should only make a small difference in the drive current - from 2.2A stock to 2.3A after the repair. 2A Shottky diodes have been pushed worse than that before ;-).