Trammel of Archimedes (aka Ellipsograph or Nothing Grinder)

SummaryThis is a classic toy that demonstrates some interesting principles of geometry and mechanical motion. It is sometimes called an "ellipsograph" because it traces a perfect ellipse. Here is a detailed description from Wikipedia with an animation of the "grinder" in action: http://en.wikipedia.org/wiki/Trammel_of_Archimedes This is my own design, but it mirrors many well known versions that have fascinated kids (and adults) for thousands of years. Note that the handle has a hexagonal hole underneath that allows you to insert a cut-down pencil for ellipse drawing. The motion is hypnotic and I hope you have fun printing and playing with this version of the Nothing Grinder. Note: This model was designed for a printer with support material capability (Stratasys BST). The handle, rail, and rivets can be printed without support material. Only the base requires support and could be easily modified to facilitate printing on a printer that does not incorporate support capability.InstructionsThe Nothing Grinder is very easy to assemble. Just print 2 copies of the rail, two copies of the rivet, one handle and one base. Slide the rails into the base. Position the handle so each hole clicks on to the corresponding rail. Insert the two rivets in the handle holes to lock the handle to the rails. You are now ready to play and/or start drawing ellipses!