Here is what I consider the ideal HS design.
-- 80 mm area
-- all copper with polished base (as thin as possible)
-- topped with max number of round copper pins made perfectly spherical and as small as possible (like a hair brush) about 1 inch high
-- made so you can attach any 80 mm fan about 1/2 to 1 inch above the prongs (for air flow)
It doesn't matter if it's AL or CU, but I'm guessing that you have to use CU in order to extrude the small prongs.
Now, if only I could test this design.
-- 80 mm area
-- all copper with polished base (as thin as possible)
-- topped with max number of round copper pins made perfectly spherical and as small as possible (like a hair brush) about 1 inch high
-- made so you can attach any 80 mm fan about 1/2 to 1 inch above the prongs (for air flow)
It doesn't matter if it's AL or CU, but I'm guessing that you have to use CU in order to extrude the small prongs.
Now, if only I could test this design.