Solarforce LC-XML2 U2 Drop-in Not Working

So I ordered a bunch of hosts and drop-in’s from Solarforce and I’m having trouble with one of the bulbs (I’ve already contacted Solarforce but between the 24 hour reply time for emails and 3 weeks to ship anything, you guys may be able to solve my problem before they even send me the next correspondence)

One of the drop-in’s just wasn’t working; put it in, put in a battery, click…. click, click……… click click click click click click click click click click. Nothing. So I tested it in another host, with a different battery. Nothing as well (now we know it’s the bulb). Upon closer inspection, the top half of the bulb (the reflector portion) was unscrewed and sort of wobbly. See picture bellow to see which parts I’m referring to.

So I tightened it down (finger tight) placed it back in… still nothing. Different host and battery, still nothing. I finally unscrewed it fully and took the above picture. I noticed that the blue label, which I assume is used to keep both the body and reflector together, was kinda beat up and wasn’t holding them together any longer. See the comparison of the blue labels bellow.

The only way I can get it to work is if I unscrew the reflector ALMOST all the way off, then put it in the host. This seems unnecessary and may damage the bulb if I drop it one day as the reflector won’t be properly seated.

Any ideas? I would hate to send it back and wait on another one to arrive (I’d be an old man by then)

Thanks!

Sounds like the bottom of the reflector is shorting the emitter lead wires. Put a better insulator between the emitter and reflector or cover the solder connections with electrical tape or something similar.
If you can solder you could resolder the connections so that they are flatter.

+1 - check those wire solder conections - maybe sticking too far up? It's easy to test the pill separate from the body and reflector using one cell and one jumper wire, but sounds like you know the pill works, but doesn't when assembled with the reflector, so most likely is what Hi-Beam says.

It looks like the reflector is the type with a flat bottom, so could very well be grounding on the wire solder joints.

That tape is probably just a modest attempt to keep the reflector from unscrewing - little weird being there... I would remove it because it's at a place that may get pretty hot.

Email them about it; it may take them them a few days to respond. I’ve only had one problem dropin, out of many orders and they were glad to give me an exchange for the problem dropin.

It’s a foil tape, people have used worse, I do remove it from my solarforce dropins though.

Check the spring, if the spring is loose or not connected very well that could be your problem. If the spring is connected well then it’s what the above posts said.

Try some tape or thin plastic to isolate the wires.

Good luck.

Bought my first p60 gear recently, and really unpleasantly surprised by the lousy design / implementations… :frowning:
No heat path worth mentioning…
Stupid spring and unused head space.

uhm… this is about a p60 dropin, right…?

Why on PILL is an o-ring? No one of my P60 has gaskets

Well spotted, I didn’t notice that. The only “O” ring supplied with a Solarforce host that could fit is the one that seals between the body and head.

I leave the tape on my drop-ins until I can mark them with identification, it’s a pain to have a few without markings and trying to pick the one you want.

Solarforce started with pill o-rings awhile ago and they do serve a purpose. I’ve had pills loosen up after changing the batteries a few times. That tight o-ring keeps the two parts together. Since the o-rings never had a head loosen up.

Well, looks like you guys are correct about the solder. One of the contacts looks like it is sticking up and rubbing against the reflector.

Fortunately, solarforce has already shipped a new one out (with tracking which was really nice) so I’m not even going to fool with it. Next time I’ll know how to fix the problem.

Thanks for the great info guys!

On a side note, I have both solarforce LC-XML U2 and now the LC-XML2 U2 and I can really see a difference in overall brightness. The older LC-XML U2 (mirror reflector) seems to give off more light when compared side to side with the LC-XML2 U2. I know that they both have CREE XML LED’s in them… but is it the orange-peel reflector that accounts for the difference? I’m running both on single 18650’s but I was hoping the newer drop-in would perform better.

A few issues going on here:

  • XM-L2 U2 should be 12%-20% or so, everything else equal
  • XM-L2's have a higher Vf than XML's, so, this means you may have to try to reduce resistance for a single cell XM-L2 (lower resistance battery, thicker wires, etc.). If you don't it's possible the XM-L2 P60 will be running at lower amps, therefore losing some of that 12-20% advantage, maybe all of the advantage
  • judging brightness is difficult. A lightbox will tell a more accurate story. SMO's will usually throw better (tighter looking center beam) while an OP will fuzz out the center beam, improves the smoothness, but should keep pace with the SMO for total output (lumens)