Today I tried this ugliness:

Circles' biggest outer diameter is about 45 mm. Supposed to be 2 channels, both bad. Heh.

Midpoints, which should give equal values, aren't the same.

It is very sensitive to alignment. It is not surprising on its own, but the level of it is.

I need to come up with an arrangement, which mitigates at least a few of the potential errors from mechanical inaccuracies.

• Plates not perpendicular to the axis (thus not parallel to each other)
• Axial rotor movement. From imperfect bearings.
• Eccentricity of either parts.

Also electrical noise suppression. Have to research that net pattern used on touchpads and other capacitive sensors. Do I even need that, or plain fill is good enough?