My book, A BEGINNERS GUIDE TO 3D PRINTING: 14 SIMPLE TOY DESIGNS TO GET YOU STARTED is now available. If you want to design your own stuff, but thought it was too hard to learn, it isn't. Take a look. I've also written an app, "How To Make A Science Fair Project." I am the author of "Doable Renewables," "Haywired," "Amazing Rubber Band Cars" and "The Flea and the Bee." I also have published articles in Popular Science, Circuit Cellar and Robotics Age. @EngineerRigsby