Now that Defense Distributed is on the defensive, it’s time to think a bit harder about what 3D printing really means. To that end, Michigan Tech is sponsoring a Printers For Peace contest that is encouraging designers and engineers to make amazing stuff using a 3D printer that can change the world for the better. “Unfortunately, the only thing many people know about 3D printing is that it can be used to make guns,” writes Dr. Joshua Pearce, founder of the project.