Just saw something in Discover Magazine about the world largest 3-D printer, using metal. This is from Space.com:
This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.
The rocket that blasted into space from New Zealand on May 25 was special. Not only was it the first to launch from a private site, it was also the first to be powered by an engine made almost entirely using 3D printing. This might not make it the "first 3D-printed rocket in space" that some headlines described it as, but it does highlight how seriously this manufacturing technique is being taken by the space industry.
Members of the team behind the Electron rocket at US company Rocket Lab say the engine was printed in 24 hours and provides efficiency and performance benefits over other systems. There's not yet much information out there regarding the exact details of the 3D-printed components. But it's likely many of them have been designed to minimise weight
while maintaining their structural performance, while other components may have been optimised to provide efficient fluid flow. These advantages – reducing weight and the potential for complex new designs – are a large part of why 3D printing is expected to find some of its most significant applications in space exploration, with dramatic effect.