See my Thing on Thingverse with the glue-less clip-together assembly parts. http://www.thingiverse.com/thing:485101

And also a cutting tool for rapid, safe cuts of Coroplast! http://www.thingiverse.com/thing:482141

Still need  a high-reliability BLDC drive motor-- have a little brush motor for now, needs a frame to stand on and also to suppose the other parts. Oh yeah, and software/drive electronics. This is going to take a while, but you'll have about 72 hours of 3D printing to do to make all the parts anyway!