I made a polargraph and documented the process on this blog.

http://makingmachinesformaking.blogspot.com/

All of the fabricated parts are made from acrylic and cut with a laser. These are the files for 1/4" and 1/8" pieces. i drew them all in Rhino and made a Adobe Illustrator and Auto Cad file of each.

Step 1: Quarter Inch

Here are the files for the quarter inch pieces. I was using an Epilog Zing that had a 12' x 16" bed hence the orientation. There is a Rhino file and also a Adobe Illustrator and Auto CAD file too.