3D printers are not Star Trek-style replicators. Most 3D printers can only fabricate parts in a single material and that material is usually some form of plastic. But multi-material 3D printers do exist and by taking that idea to its limits, a team of researchers at MIT was able to build this 3D printer that can produce complete and functional electric motors.

The team didn’t have to start from scratch, because they were able to use an E3D ToolChanger 3D printer as the foundation for this project. That printer model came out several years ago and is now discontinued, but it was and still is pretty unique. It can swap between toolheads on-the-fly to print with different materials, which is a capability most users take advantage of to print with multiple colors or multiple kinds of thermoplastic filament material, such as PLA and PETG.