@Catdaddy posted:So I am going to take a shot at this. MELGAR, correct me if needed please, as I am not 100% on this. The spiral curve is always changing, growing or shrinking, it never straightens out, even at the very end. It wraps into itself. If you were to splice into the spiral, Or follow a tangent line from the curve....that makes it an easement. Look at the tangent line graph in MELGAR graph. Hopefully, I put out a good explanation, please tell me if I did not. Think of the spiral like a ‘French curve” that connects two straights.
Yes, that is exactly what I was thinking, except a French curve that connects a straight to a circle or arc. Or two French curves mirrored that connect two straights.
I had forgotten that I used to use French curves back in the days of hand drafting for just this application. In CAD, I think this would be a curve with bezier points. You would snap to the straight and to a tangent on the circle and then pull your bezier handles to get your easement. I have designed news desk tops using this technique.
