About this 3D model

I have 24 feet of extruded aluminum that my corporate office gave away in the form of a 12 shelf display case. After taking it apart, I found that I have enough 40mm x 40mm extruded aluminum to make five printrbot-type 3d printers. I've spent about 15 hours on design and expect to put another 30 into the project before I crank out a bot.. This is a work in progress.