Turning shapes other than cylindrical

[Karl_H]

Interesting!

Have you considered reversing the placement of your magnetic base and the drawing so that you are looking straight down on the drawing to make it easier to hit your lines?
Also, have you considered using a pattern made from 1/8 inch aluminum of (heaven forbid) plywood or hard board, rather than the paper drawing. (Let's make a simple idea way more complex.)

Thanks for sharing.