I got my 10 degree ruler from Phllips Fiber Art today. There was a flyer in it for a slotted cutter for Drunkard's Path or other circular needs with a variety of sizes. Here's the medium. There is a really cool video on how to use different ways. Add another to the want to do list.
http://phillipsfiberart.danemcoweb.c...-a-round-tool/