Rings and shims of the spindle moulder shaft proved very versatile and turned out perfect to settle tools. Fine adjustment can easily be performed adding an only aluminium angle or tube. Taking account the working tool contacts the rule at its middle, a one millimetre gap between rings and rule on one side means a half a millimetre more than the ring pile. Depending on the tube length that method enables accurate adjustment. As shown below and whatever the tilting angle of the saw blade, protrusion can be set without measurement.

The same way provides depth and height adjustment for spindle moulder working tools. Finally the workpiece leads the continuity plate location and no measurement is required.

That method works fine with router and drill press and so forth... Here are the circle jig details.