“This idea was inspired by all of the CD-Rom CNC machines that I’ve seen on Instructables. I’ve seen them used as drawbots, laser cutters, drill presses, but I haven’t seen one yet used for a 3D printer…at least not a reasonably priced one. So the goal of this instructable is to show you how to make your own 3D printer from old CD-Rom drives an a cheap 3D printing pen.”