need XM--L on 2mm-thick board

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peteybaby
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need XM--L on 2mm-thick board

Hello there.  I recently screwed up a mod of my PT Apex headlamp, and I'm now looking for an XM-L mounted on a small MCPCB board so I can replace the LED again.  I will need to file down the board to fit, but the essential requirements are:

- LED and both + and - solder terminals are "in line", so that I can file the board into a 4-7mm-wide strip and not lose any PCB tracks

- maximum length of finished strip (and therefore max diameter of board) is about 15 mm

- board must be 2 mm thick, or slightly thicker.

This board, suggested by Match (thanks) meets my criteria except for the thickness... this one's only 1 mm thick: http://illuminationsupply.com/cree-xml-128mm-round-mcpcb-t6-1c-tint-p-34...

Any ideas?

Don
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1mm of shim stock at the back of the star? At least if someone near you sells it.

That's probably the easiest way. Use a little thermal adhesive to stick it down and it should help a bit with heatsinking.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

peteybaby
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Hi Don. Thanks... I was thinking of shimming it somehow too, but I don't know what material I could get, or where to get it.  I have aluminum tape but it's too thin, and has adhesive on one side.

Also, I figure that the fewer junctions between different materials there are, the better the heatsinking will be. With a shim, it would be LED > MCPCB > thermal compound > shim > thermal compound > heatsink.  It might be okay (I've never used a shim in this way) but if I can find a 2mm-thick board, I'd rather try that first, even if it means more filing to get it down to size.

Don
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Makes sense. You should be able to get shim stock at any metal factor. These guys in Surrey (Ca - didn't know there was a Surrey there) might have something useful in stock.

http://www.metalmart.ca/products.html

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

JAS
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If you have one more PCB(not necessarily for XML) of same size,  then sanding the top and glue it the XML PCB might help. Alternatively you can try several pieces of thin aluminum sheet.