Thanks for the idea Chris. Unfortunately these aren't made that way - I know because I've just spent 20 mins with some files and a junior hacksaw.
Basically the top and bottom contact appear to be a single piece of metal running all the way through the full thickness of insulated board. This becomes obvious when you start cutting into the board. It is also flippin' hard - significantly harder than mild steel!
I have a replacement set of LEDs on the way from Cutter. What I'm going to do is mount them on a thin square of brass or copper sheet just large enough to cover the central heat conductor. I'll epoxy them on, then epoxy the emitters in place once the spacers are set.I figure 0.4mm of silver adhesive ought to be adequate as an insulator and should stop a build up of conductive materials underneath the connections.
And talking of that, these contacts are the most reluctant things I've ever tried to solder to! Bearing in mind I build guitar amps for fun and have a good iron, I just could not get the solder to flow. I wonder if too much heat is being conducted away. The spacer pad should help there too. Looks like buying them pre-mounted on stars was a good idea after all.
The XR-E based lightset is almost finished but I've managed to screw up mounting one of the LEDs - the Cree units are even smaller than the K2s, and need insulation as well as thermal transfer on the underside and one LED is now earthed to the housing. The Square section tube design *looks* cool but is a complete toad to fabricate without a workshop (i.e. on the kitchen table).
Chris - did you get that email from Cutter? They've up-rated all XR-E emitters to 1000mA constant now. They're talking about 260 lumens output per emitter, but I suspect lower bins will only achieve 220-240ish. It's a big bucketful of light though, for something so small.
Ancient Mariner
