[youtube=http://www.youtube.com/watch?v=Mhu3zojL5Y4]

[Jeri] put together an absolutely massive Etch A Sketch for The FatMan and Circuit Girl show. She had removed the DLP chip from an HD rear projection TV and decided to repurpose the 52inch screen. The movement mechanism uses pulleys from screen doors with nylon lines. The two sets of lines are fed in a criss cross pattern so that the parallel lines move in the same direction. The lines move tent poles in the x and y which controls the movements of the golf tee stylus. It’s driven by two high torque motors from $9 Harbor Freight 18V drills. They tried several different powders, but ended up using aluminum powder from an original Etch A Sketch because it sticks to everything. It will eventually be hooked up for IRC bot control once they get a large enough h-bridge.

[via adafruit]