Improved Printable Panel Clip for Lulzbot Mini 3D Printer

Printable, Strong, Hollow clip for attaching 3mm Acrylic panels (http://www.thingiverse.com/thing:994992 and http://www.thingiverse.com/thing:756211 and http://www.thingiverse.com/thing:756173) These clips are a good replacement for the lasercut acrylic clips (http://www.thingiverse.com/thing:756173) Same profile, but tweaked for a better fit when printed, and modified (see cross-section view) to provide good strength, and flexibility, with minimal material, and good strength. These do requir