Looking for ideas on sources for heatsinks. I have a bunch of these Cree XR-E's on 16mm sinkpads (entire backside is exposed metal that's isolated from the circuitry) that I've pulled from flashlights that I've upgraded.
I'm going to use them for random lighting fixture projects, so I just run them at 350mA but they still could use a heatsink. Anyone have any ideas for random sources of unconventional chunks of copper or other solderable suitable metal that I could use? I have a variety of aluminum IC heatsinks and whatnot but aluminum doesn't take solder.
Perhaps someone could tell me, if I went to a hardware store and picked up some heavy bolts, is there any particular kind of metal they come in that would take to soldering? Heck maybe just use a roll of pennies and still be cheaper on face value?