Advice Requested for Best Method of Removing Luxeon from Heatsink

Advice Requested for Best Method of Removing Luxeon from Heatsink

I'd like to reclaim a couple emitters back from their original heatsink. However, I've done this twice without problems, but the third time, was disasterous. I now have a brand new Luxeon paper weight, never even got powered up. The nice blue LED is still mounted securely to the heatsink, and the lens assembly, with phosphor in it, is sitting next to it.

Any 'secrets' would be appreatiated, so there are no repeats of my last experience.

I've ben using an Xacto knife blade handle with flat razor blade. Worked real good twice, and seemed to third time, but the lens assy just popped off by itself.

All advice welcome

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by lambda:
I've ben using an Xacto knife blade handle with flat razor blade. Worked real good twice, and seemed to third time, but the lens assy just popped off by itself.
<HR></BLOCKQUOTE>

I guess I'm no going to be of much help then, because that is just about what I was going to suggest.

The only difference is that I use one of those wider bladed retractable razor knives (the infamous "box cutters" preferred by terrorists everywhere )

I'm very gentle- After snipping the leads, I slowly work the edge around the base of the emitter, in a complete circle, several times, with slightly increasing pressure, until the emitter pops off.

Snip the leads?

You don't just desolder them?

Since our competitors can now buy the emitters by themselves, here's our trade secret:

We uses a hand press with a piece of aluminum strip shaped in a upside down V. The foot of the press is a H. The LS board is placed between the two and the handle brought down gently. The board is bent away from the LED in a V cleanly peeling it from the back of the LED. Be sure to line the LED leads parallel with the H so no differential stress is place on the LED or it's leads. No part of the tool or the press should touch any part of the LED itself - remember these are very fragile in this state.

If you really want, I will post a picture of the setup. It's actually pretty simple, works fast and is consistant.

We looked at zillions of ways to do this and at one point I thought I would have to cancel our LS offering because we could not come up with a way. Most of the ideas either stressed the LED (causing large differences in brightness from unit to unit), broke the bond wires or snapped the leads off.

We tried solivents, chisels, grinders, heat, etc. We bugged the Lumileds engineers on how to remove these and they suggested solivents or chisels (!), which we tried of course. I also bugged them to produce the emitters by themselves, but it looked like they would never provide that option (which they finally did later on).

I was pretty stressed about this and was having trouble sleeping. Like I said, it was a potential show stopper for the LS.

One morning I got a call from one of the engineers at our electrical contractor and he said, "I solved it". I couldn't beleive it and ran over to their shop. I was so happy I paid the guy $100 on the spot. He earned it.

So, anyways (long story!). That's the slick way to pop these off the board.

Peter Gransee

Peter,

Thanks so much. I was looking at folding the heatsink back away from the LED, you've just confirmed that theory. I'll try that method and see if I can make it work.

gransee that the best method i have ever heard of and you of all people would know. lambda good luck trying it and tell me your results... Bushman

Peter, thanks again!

Yes, it works like a charm. This particular one had been modified already, so the heatsink was a 3/4" round shape. I just scored a line on the back of the heatsink with a hacksaw parallel with the desoldered leads, and placed in vise and slowly cranked up the pressure on the edges. The heatsink bent right along the line, which exposed the back of the heat slug on one side, and I finished up with the razor blade since I was sure it was cutting under the exposed heat slug. I can see where this would work great with a new full size heatsink and press like Peter described.

I should have thought to ask about this a couple weeks ago before I made the Luxeon paper weight.....

cool i am glad that it worked. now my friend what are you going to do with that bad boy!! (i know which luxeon you are talking about (its from mark hannah by the way...)

No, those haven't shown up, so I'm sacraficing one of my personal flashlight mods to satisfy my mod habit.

Actually, I'm making a Mag 2D/3C mod for my dad. Need it for his birthday and can't wait on parts any longer. He's a big time camper/explorer and is always destroying flashlights on his adventures. We'll see how long this one lasts....

Have to remake my own DB AAA mod when the parts do show up.

Btw, the LS w/optics that we are selling from our website will go back up the normal $14 from the $12.50 tomorrow morning.

These have the new NX-05 optic, stock heatsink and white LED.

Peter Gransee

lambda what did you do with the luxeon that i sent you? just curious...

Bushman, that one is in my DB AA mod.

[ QUOTE ]
Gransee said:
<P>If you really want, I will post a picture of the setup. It's actually pretty simple, works fast and is consistant.<P>

[/ QUOTE ]

If it's not too much hassle, could you?

-Dan

This might help: http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Board=UBB14&Number=133953&Forum=UBB14&Words=pcb&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=allposts&Main=133937&Search=true#Post133953

Kirk