Spirographs can make some pretty groovy designs on paper, but what if you want to take it a step further? [Uri Tuchman] has used the pantograph on his milling machine to duplicate the effect in harder ...

What is spirograph: A geometric drawing device that creates intricate patterns using gears, developed by Denys Fisher in 1965 and now a Hasbro trademark. Why it matters: Spirographs teach geometry, ...