3D-Printable Laser Cutter

This is the first release of the Boot-strappable Open Laser Cutter project that I've been working on for the past few months. The goal of the project is to construct an open design laser cutter with a large cut area (about 1 meter square), for about 5%-10% of the cost of a commercial system. The design draws heavily from other open laser cutter projects out there (such as the Buildlog 2X Laser Cutter) in using inexpensive aluminum extrusion and optics for most of the structural frame, while here most of the custom parts are 3D printed from ABS. The printed parts represent about 10 hours of total printing time on a Makerbot or Reprap, and have been designed with the hope that they would be of general utility to anyone printing out a large CNC system -- not just a laser cutter. These include parts such as NEMA17 motor holders that mount onto t-slot, idler brackets, pillow block bushing mounts for motors, idlers, and shafts, and so on.