About difference.
I see only smallest difference in chanel width.
And the 2nd block is durtier
Jaydee: I don't think that manufacturing with slit saw could made such difference. Anyway I can't see how to make such channels otrherwise than with slit saw.
Making that block with end mill would take about 30 minutes just to make those channels.
Perhaps the copper material is difference, and the worst is made out of les condustive copper :shrug: