another question:
The copperbars i have are 10mm thick and then i have a piece of 5mm. I wonder if i should use 2x10mm bars to make the WB or use a 10mm as base and a 5mm as lid.
If i use the 2x10mm i could drill holes in the top piece as well allowing more water to get thru, but if i use the 5mm plate as lid, only the 10mm bar would act as coolant.
The latter one would increase pressure ie. velocity, but the first one would be less restrictive...
I notice some of your WB on your site (#Rotor) stand 19mm tall so i guess you use 2 x 10mm bars..?