Here are scans of four CAD images that I drew off of the woodcut from page 189 of John Collins' Perpetual Motion: An Ancient Mystery Solved?. I enlarged the woodcut a little over eight times and then made measurements to about .05". The CAD program showed the white segment to have an angle of 25.434°. And if the angle is from the center out to the width of the white segment, it is 21.724°. I couldn't discern a line of any particular width between the shading of the large pie shapes and the white circle just inside of it.

A possible interpretation of this drawing is that the narrow pie-sections represent the maximum swing of a pendulum and bob with its bearing being away from the central axis of the whole wheel. This would allow multiple weights (like three, as in this drawing) to be within the same plane of the wheel.