The National Renewable Energy Laboratory's new robotic metal 3D printer is speeding up prototyping and small-run component ...

Learn more about stack 3D printing as well as the pros and cons of the process and how you can accomplish it on your own 3D printer thanks to the team over at Keep Making. Watch this video on YouTube.

This 3-D printer can fit in the palm of your hand The proof-of-concept device is a step toward making the technology more portable This prototype 3-D printer is roughly as long as a quarter is wide.