Digitizer?

I'm thinking of making a digitizer by connecting a fixture in the mill's
spindle to a high resolution encoder to a ball-tipped arm that is
torsionally pre-loaded, and have the mill move around the 'part' in a
specified pattern (which would be calculated from the results of the
'previous path'), and readout the encoder at every .005" of the path, then
calculating the exact position of the ball (via the sine of the ball's
radial disposition as measured by the encoder) to get a tangential envelope
at varying 'Z' axis elevations on the part's surface. Is this "do-able", or
has it already been done, and I'm 're-inventing the wheel'?

RayHex

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