Dear all, Now that I've seen the news on the stolen equatorial in Germany, I remember I once made a similar design for Pov-Ray (a 3D renderer). it was an equatorial with a spindle-shaped gnomon so that it showed true (or legal) time, instead of solar time. The gnomon was rendered by brute force, this is, cutting a cylinder with rays from the hour points to the sun, but I wonder how could I derive some implicit or, better, parametric equations for such gnomon in order to introduce them in a CNC machine, for instance.
Any hint or pointer? Regards, Anselmo -
