Surefire L2 with Cree MC-E

[LLCoolBeans]

I intend to use thermal compound to attach the body of the emitter to the riser. Once that is centered I'll solder the emitter legs directly to the riser to make the jumper connection. Then I'll solder a couple of 24ga wires to the airborne legs for the positive and negative connections. After that's done, press the emitter into place smear everything with compound and insert heat sink.

This is my first modding project, so if I'm doing something wrong please speak up.

Thanks

 

[Energie]

One question: how's the donut? Is there an X-shaped null void at the center?

The "X-shaped donut" is slightly visible at short distances (1-2 feet) on a white wall.

MC-E, distance 3 inch (SF L2 on high)

MC-E, distance 10 inch (SF L2 on low, pic underexposed)

LLCoolBeans:
I´ve seen your question about soldering in the machining section.
Silver is an excellent heatsink.
But there is a problem. The thermal paste between the silver heatsink and the MC-E leads the heat from soldering direct to the dies. I think, more than 1-2 seconds soldering may damage the MC-E.

 

[LLCoolBeans]

I´ve seen your question about soldering in the machining section.
Silver is an excellent heatsink.
But there is a problem. The thermal paste between the silver heatsink and the MC-E leads the heat from soldering direct to the dies. I think, more than 1-2 seconds soldering may damage the MC-E.

Dang! That throws a monkey wrench into the works. It's definitely going to take more than 1-2 seconds.

I guess there's one way to find out for sure. :sweat:

Anyone else have an opinion on this? Am I going to cook the emitter trying to solder the legs to the silver riser?

 

[mudman cj]

Its not advisable. But, you could insert a thin heat shield between the silver and the LED thermal pad while you solder, then remove the shield, work thermal grease/adhesive into the gap, and press into place. This will bend the LED leads slightly, but will not break them. The hardest part will be working the thermal grease/adhesive into the gap.

 

[LLCoolBeans]

Its not advisable. But, you could insert a thin heat shield between the silver and the LED thermal pad while you solder, then remove the shield, work thermal grease/adhesive into the gap, and press into place. This will bend the LED leads slightly, but will not break them. The hardest part will be working the thermal grease/adhesive into the gap.

That would be more work than just doing away with the riser/jumper combo altogether and using a wire like Energie did. The only reason I thought of the idea was to make less work for myself and not have to change any of the original components. I can always just cut off the little ears on my riser and drill two additional holes in the heat sink for the jumper wire. Looks like that may be what I need to do.

Dang! And I thought my solution was so slick. Oh, well, live and learn. It is my first mod after all.

 

[Energie]

I think, a jumper wire is the way to go.
You can lead the jumper wire through the stock heatsink,
or:
drill two small holes and use a small file to make room under the silver heatsink.

 

[LLCoolBeans]

That's a fine idea, but I don't think my riser is thick enough to accommodate a groove deep enough to envelop a 24ga wire with insulation. This also would reduce the amount of surface aria in contact with the heat sink.

I'm going to rethink this tonight, but I'll probably just end up drilling two new holes in the stock heat sink.

Thanks for your help on this guys.

 

[LLCoolBeans]

Well, I got it all back together finally. I had a lot of trouble learning to solder wires to those tiny emitter legs. That was a lot more difficult than I had originally imagined. Got the hang of it eventually though, but there was one casualty. Luckily I bought two emitters.

Cut the ears off of my riser and used a jumper wire.

It's working now, but I'm not seeing any noticeable increase in brightness. It would appear to be about the same brightness as the Luxeon 5 was. Except for that the Lux 5 had a nicer tint and less artifacting. Dang! Did I do something wrong?

No doughnut but the X is pretty prominent.

 

[DaFABRICATA]

It should be noticably brighter than the LUX V.

I run mine on a single RCR and its still way brighter than a stock KL4.

Sounds like there may be a problem....are you using FRESH batteries?

 

[LLCoolBeans]

It should be noticably brighter than the LUX V.

I run mine on a single RCR and its still way brighter than a stock KL4.

Sounds like there may be a problem....are you using FRESH batteries?

Yea, that was the first thing I tried.

 

[LLCoolBeans]

It's a WD M bin. Spot appears white, maybe slight yellow tint. Spill is purpleish :green:. Old Lux5 had a nice even slightly warm beam.

Could something be shorting? I'm guessing if something was shorting, it just wouldn't work at all or work briefly then self destruct. I did solder and resolder the legs of the emitter to the wires several times before I got it right. Could I have over heated it when soldering? What if I got the polarity reversed? It's a diode so electrons should only flow one way, right?

Dang.

 

[Energie]

How much is the current drawn from the batteries (see post #15)?

 

[LLCoolBeans]

How much is the current drawn from the batteries (see post #15)?

How do I test that?

 

[Energie]

Remove the tailcap of the light.
Use a multimeter, one tip on the light-body, the other on the "-" contact of the battery.
Current should be at 1,0 - 1,1 A (two fresh 3V batteries).

 

[LLCoolBeans]

Remove the tailcap of the light.
Use a multimeter, one tip on the light-body, the other on the "-" contact of the battery.
Current should be at 1,0 - 1,1 A (two fresh 3V batteries).

I'm reading 1.25, what does that mean?

 

[Energie]

Perhaps the batteries are not new. 1,25 A with used batteries is ok so far.
If the MC-E is wired correct (and without a short) I suspect it has been damaged during the soldering.
The MC-E is far brighter than the Lux5 (see post #1).

 

[Icarus]

It's a WD M bin. Spot appears white, maybe slight yellow tint. Spill is purpleish :green:. Old Lux5 had a nice even slightly warm beam.

Where did you buy your MC-E's?
Any updates on your mod?

 

[LLCoolBeans]

The WD M bin I got from Kaidomain.

I have a couple of 5As coming in any day now. I was going to try again with one of those. I have to assume that I overheated the emitter while soldering it, since that is the only info I have to go on.

 

[Icarus]

The WD M bin I got from Kaidomain.

I have a couple of 5As coming in any day now. I was going to try again with one of those. I have to assume that I overheated the emitter while soldering it, since that is the only info I have to go on.

:thanks: keep us updated about your mod. :thumbsup:

 

[Icarus]

Very nice mod Energy! :twothumbs