[Azathoth]

I have a suggestion. Instead of CNC'ing something that small. Why not make the process easier by making the entire arm of the hopup unit?

You will have far more space to work with some designs.

What would be excellent is a system where their is another spring or tensional device on the hopup arm that allows the arm to shift slightly as the BB passes past it like a fly wheel). Then that way the dial on the hopup unit that we can adjust backspin via spring stiffness on the hopup arm AND the dial we have on the hopup units that we use traditionally.

Are you on Airsoftmechanics?