RED LUXIII shorted to.....

Ok, I just mounted my new Red LUXIII to my Osink, and now the pos. base is shorted to the Osink..(I was warned and thought I was careful, but) used AA Epoxy... What now..?? Should I hook the + of the batt to the barrell.. How can I insulate this thing.. I don't want to "break" this new LuxIII off the heatsink...

help the doofus..

skillet

OK, so your heatsink is now connected to the positive side of the LED. Can you insulate the heatsink from the negative side of the circuit and use it to feed the positive to the LED instead? Will this interfere with its transfering heat to the body of the light?

I dont think so.. I'm gonna put it in a Mag body... Oh goodness... what a world

skillet

I think you're pretty much stuck with having to remove the Lux and re-do this. A thin piece of paper b/w the Lux slug and sink might work.

Seems this has happened to a few others recently. I think having the sinks Type II anodized is the best solution. Anodize shouldn't present problems with using a white emitter or star.

Larry

I got the emitter off, but can seem to figure out a way to insulate and not loose the ability to line the sucker up.... keep 'em coming yall..


Skillet

Ok you got it off! That will make things a lot easier!! Clean it up good, scrape any excess epoxy off of it, as well as the o-sink.

Ok, when you go to re-do this, mix up enough AA to cover the o-sink surface, up to the edges of the self-aligning ridges. Then slather some on the slug of the luxeon, Press and rotate till it locks in, press down in the center once more. Then wait a little for it to start to harden, and test the resistance of the postive slug and the HS. If you're good, well, good!

That's how I did mine and it worked fine.. If it still doesn't work, then you'll need to put a THIN layer over the slug or HS first, then put it togther, Just make sure it's not too thick to keep the Luxeon from touching the HS fully..

If this is a LuxIII red then you defienalty need the full contact of the HS!

I'd agree with the anodising method to insulate it. Now that you have the emitter off, can you go get it anodised?

I have 2 R/O LuxIII's AA epoxied on new style C-cell O-sinks doing the same thing.

The first one wired to a 2 cell Mag flashed on really dim and stopped working. In my zeal to get the O-sink out of the Mag I broke the negative tab off. Once I removed it from the light and started putting power to it it lit up full brightness putting the positive to the sink and the negative to one of the tabs on the side.

The second one I checked with the ohmmeter and am getting continuity from the positive to the sink. I epoxied this one after the first fiasco and made sure to lay a good bead of AA along the edge of the "locks" before covering the bottom with the epoxy.

What is the best way to get the Lux off of the O-sink?

Thank you so much for the help here at this place.... man.. just awsome.. to the point..

Got the emitter off buy using a very small blade knife prising under the emitter through the epoxy "bleed" port on the heat sink...

Tried to glue a piece of plastic, black tape, different things and all these effort made it impossible for me to align the emitter into the heatsink..

So.... I put a very, very thin spacer into the sink, slavered on the epoxy and measured and "eyed" and measure and adjusted and when the epoxy set.. I quit worrying about it..

(2) teflon coated wires, (1) .47 ohm 5watt resistor, (2) silicone coated wires, (1) modified mag switch, (3) alkalineS later.... and my family has never seen things in this "light"....

TO COOL FOR WORDS....

Thanks for the suggestion and help again...

Skillet....

PS ...I don't have any thermal test equipment... how hot will these run... and will I kill it with this set up....

PJ: I'd heat up the O-sink some how, perhaps in a toaster oven, but not too hot! That will soften the epoxy. Then I'd get a small needle, and where the channel is cut out in the o-sink for the excess epoxy to ooze out, press the needel into that. Do that from both sides and maybe try prying up once you get the needle all the way across a couple of times. That way you'll be pressing up on the slug. Otherwise you go from the side and you hit the case of the led and it will break!!

skillet: well, what kind of spacer did you use? AA epoxy will conduct best next to bare aluminum... And these run 1.4amps @ around 3 volts = 4.2 watts!! That's as much heat as a luxV almost! PLUS, the reds/ambers get dim when they get hot, so you loose photons! So you need to keep it cool!

I used a piece of electrical tape.. but it wasn't even 2mm in diameter.. About the size of a pencil led... I just wanted something in there to keep the emitter raised ever so slightly.... and I smother it with AA... If the epoxy conduction is as good as I hope, it should still "sink it" alright.. I want use the light very long at a time anyway...

Noone here can stand it.....

And that is just the way I like it!!!


Skillet

Well, the tank is out of acetylene so that idea is out. A friend has a variable heat gun I may try on the broken one and see what happens.
I wonder if there is a sharp edge on the aligning tabs that is cutting through the epoxy? The sinks I have now have machining marks on them and the older ones seemed to have a matte finish from being tumbled , IIRC. I'll see what I find and post back here.

PJ, yes, you could smooth them with sandpaper. that should help. Also drop the emitter straight down where it aligns and try twisting only one direction till it stops, then back the other direction just slightly, so you're not pressing up against the edge of the aligning "tab".

red family of luxeons will all fail if die slug is permited contact to ground.

best way to handle red luxeon is to smear thin layer of AA epoxy to entire base.

let set to form insulation layer, then expoxy to heatsink

here's more info at this link at mbf: http://tinyurl.com/8wxyh

Looks like your best course of action will be to go and get a Dorcy 3D 1 watt.
Go with that instead of the magmod.
Get to the star in there.
Lift up the emitter leads with the hot pointed end of a 15-25 watt soldering iron.
Pull the emitter off the star with a pair of vise grips.
Clean it up.
Then mount the R/O onto it with either arctic alumina, or just thermal grease as the soldered leads will hold it down.
The built in resistor should be enough for the Lux3 red to be ok.
I have noticed that Luxeon1 stars are electrically isolated and will give you no problems at all with the red/amber family of Luxeon 3's.

This is an interesting issue. I have in the past made annodized O-Sinks. They were not all that well received. I thought the Black O-sinks looked great ecpecially when mounted in a black Mag Light. Some people thought the annodizing could have an effect upon the heat transfer. I have no evidence either way.
My plans are to make the next batch of O-Sinks from copper. I will look into different finishes. I think chrome is possible . I will look into noncunductive finishes.
Yesumofo