The framework is hollow, and multiple tiny channels converge at the top. It's the same principle as coolant-through twist drills for CNC machines, which were traditionally made with helical electrodes in a ram (a.k.a. sinker) EDM centre. EDM works for a constant helix, but variable helices can't be made any way except 3D printing.
The framework is hollow, and multiple tiny channels converge at the top. It's the same principle as coolant-through twist drills for CNC machines, which were traditionally made with helical electrodes in a ram (a.k.a. sinker) EDM centre. EDM works for a constant helix, but variable helices can't be made any way except 3D printing.