We made the larger (adult) version of the Flying Crank Ghost from instructions in MAKE magazine. You can find them here:(http://makeprojects.com/Project/Flying+Crank+Ghost/324/1#.UH9UNRxuYRg)
For the child’s Lego version, we started with a mini ghost ornament from Michel’s that cost $1.50. The arms were foam-covered wire with plastic hands. We removed the foam from the wire, and cut the wires, so we could loop the ends to make the joints floppy at the neck and elbows. This is all-important; it allows your puppet to move. Now you have the makings of the final animated puppet. You can also make a mini-ghost from a ping pong ball, wire and gauze, like the adult version. Just remember that the arms have to have joints that can be moved easily at the neck and elbow.
The mechanics of the crank and frame from which your puppet is suspended are the same as the adult version from MAKE. We just used Legos in place of the items in their “relevant parts” list.
Here’s a picture of the assembled Lego parts we used. But really you can experiment with any Legos you have at home. Don’t feel like you have to copy our design exactly. It’s a trial and error process (at least it was for us!)
The main things to remember are: (1) the motor has to be SLOW. Most Lego motors run too fast, but can be geared down using the plastic gears contained in any LEGO Technic set. We had a super slow motor from a Lego insect kit. (2) Copy the shape of the frame from the MAKE magazine article, but don’t worry about pulleys. Any Lego part with a hole in it will work just fine to run your lines through. (3) The pivot that turns below the end of the crank has to spin freely from the crank arm with three threads attached to it, one each for the ghost’s head, left wrist and right wrist. If it doesn’t turn easily the threads will get all twisted up.
There are many YouTube videos showing the Flying Crank Ghost and how to build it yourself. We watched a lot of them before we really understood how it works. We hope that seeing our ghosts in action at the EcoTarium helped you visualize this mini-engineering project.