bigben.. you know if you *really* want to make a good block with tiny ass holes in it.. I could sneak a block into a machine at work and drill holes for you. Those brass tubes are used in drilling (EDM=electron discharge machining=we never touch the part, just hit it with a high frequency high power spark)
We need the tubes to be hollow so we can use the water to flush out any eroded metal. Copper would be tough as its very conductive, but I think I could work with it. I can do holes as small as .010" (with a .008" electrode) but I think best bet for me to get them done before someone sees it is if I made them like .014-.015" diameter. I've actually been tempted to play with the idea of making a block in them for a while, just haven't really had much time. you could probably fit a 1/8" thick block down there, or a little less if you use a thermal pad on one or both sides of it. I have electrodes to make holes as big as about .072", but a .020" or .015" hole would be ideal for me (I already have parts I'm drilling with holes that small, can just sneak your part in and pop a bunch, heh.) I would need 2 pieces or your final part and something I can use as a scrap piece to figure out the burn settings I'll be using on the final. Holes that are completely through the part are easiest for me, if you want I could drill a bunch and then 2 bigger holes to act as inlet/outlets in a cross drilled pattern. You'd need to solder a cap on it though.
just a thought, maybe we can see this become a reality
