Hi and thanks for the welcome bigben2k
I'm not the person from the OCAU, I just registered there yesterday when "unregistered" linked that post.. I can see the similarities though
I've been thinking for a while about how to be able to make a simple microchannel block without the use of advanced mills or expensive tools. This block won't be a good idea for resellers though, since it'd be easier for them to mill a block, but the "hobbyist" I think this would be a good idea.
I said that you only needed regular tools.. You need a drill (preferrably drillpress) saw, file, sandpaper and some silversolder. The material in my pic is 1,5 mm copper sheet which should be very easy to get. Instructions to build this block would be sort of like this:
Cut a number of pieces like those seen in the picture.
Stack them as shown in picture.
Tighten the pieces together with bolts placed through the 4 holes.
Silver-solder the edges.
Drill holes for in- and outlet.
Sand and polish.
Fasten the hose-barbs.
Ofcourse you need a whole piece on each side as well, and preferrably with a bit thicker copper that will help holding the block together during soldering.