A model of the famous toy known as a spirograph. A circle of radius r (see blue circle below) is allowed to roll around the inside of a circle of radius R (see black circle below). We assume that the ...

This set, celebrating Spirograph’s 60th anniversary, features the first-ever electronic Spirograph. Kids can create thousands of designs by inserting the markers and pushing buttons to select the ...

Late last year at a craft show, [hahabird] and a friend came across a laser-cut Spirograph and they both had a go at it. After mocking his friend’s lack of fine motor skills, [hahabird] was ...

[Tuchman] starts with a quick proof-of-concept using an actual plastic Spirograph toy to make sure it isn’t a totally unworkable idea. Unsurprisingly, the plastic is too flexible to give a ...