Is there a trick to centering an emitter?

[netprince]

Hey Everyone,

I cant seem to figure out a good way to do this. I'm building a mce based m@g, and the heatsink is smooth on top, no centering ridges.

Am I missing something? Is there an easy way to center the emitter in the heatsink while the AA is setting?

 

[carbine15]

Good question. I'm curious what others do.

 

[jaygrant]

In this thread a member states he did it using the reflector to find the center. Here's the thread:
http://www.candlepowerforums.com/vb/showthread.php?t=202014

It isn't a Mag, but I think the same method would apply. I have read it on other posts too.

I haven't tried it myself.

 

[DonShock]

I use a center finder intended for marking the center of round stock. Since most led dies are square, I set the marking line across the corners and adjust by eye to get it as close to center as I can. It can be a little tricky getting the center finder close to the die without touching it. I go back and forth checking opposite corners and making small adjustments as needed until the guide line lands right on the corners with no adjusting needed. My results have been pretty good so far.

 

[Superdave]

I eyeball it.. :thumbsup:

 

[VegasF6]

It's hard. I screwed up a few times on some but found a tip here I plan on trying. Apply Arctic Alumina Thermal Compound (not the 2 part adhesive) center your led, apply devcon 2 ton around the outside.

I forget who to give credit to, just something I read in a post.

 

[Energie]

I use my small lathe to centering an emitter.

Small pice of brass.
The hole has the same diameter as the led-dome.

 

[Fallingwater]

I did it this way.

 

[bluecrow76]

I've always eyeballed it and used the reflector to check, remove the reflector and bump, check - remove - bump - check - remove - bump - check.... not graceful but I've been fortunate enough not to screw anything up yet (I've only got maybe ~20 mods under my belt to date).

It's hard. I screwed up a few times on some but found a tip here I plan on trying. Apply Arctic Alumina Thermal Compound (not the 2 part adhesive) center your led, apply devcon 2 ton around the outside.

Now that is a good idea! Have you run into any problems long term with this method?

 

[VegasF6]

I haven't done it yet. Just read it in a thread that I can't find again. Otherwise I would give the OP credit. Seems like a good idea though. Only thing I see is I need to find a good way to apply pressure to the led while the epoxy sets. I am thinking a spare optic with a tissue or something to protect it, and put it in a small hobby vise (with the heatsink horizontal)

But, I am thinking about trying this on a penta cree build soon and working with 5 of them at once sounds a little tricky.

 

[jezzab]

I know this thread is a little old, but thanks to those who listed their ideas.
I had been puzzled about this for a while now

 

[zelda]

I turned always a pit with 0.05mm depth. Its visible in this picture: