LUSBY TAYLOR'S METHOD
This elegant method, devised by Chris Lusby Taylor, uses the ancient Greek method in order to calculate the Sun's true longitude and thus the Eccentricity Effect. It then uses a geometrically correct method to find the Obliquity Effect.
Although the method very closely produces an elliptical path for the sun, it does not correctly emulate Kepler's 3rd Law that equal areas are swept out in equal times.
The errors produced are +/- x secs.
 All that is wanted is a mechanical method to simulate the geometry. This would be useful since it produces its result on an arc of a Circle - easily translated to rotation of a dial plate. Other methods of mechanically simulating the EoT produce results in a linear fashion- requiring a rack and pinion or a chain system to convert to rotary motion. 
The images above show how the two components of the Equation of Time are geometrically produced. The movies below show the geometry, both with exaggerated obliquity & eccentricity to make the geometry easier to see and with the true values. It must be borne in mind that a 1° arc on the circle is equivalent to 4 mins of time (360/24/60)
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