This is an open-source clay extruding print head that can be used on numerous 3d printers. It is a work in progress. It is based on pioneering work by Unfold http://www.thingiverse.com/unfold/about , Jonathan Keep http://www.thingiverse.com/JKeep/about , the Wasp Group http://ow.ly/Zt2tz , and more. The project was initiated by Tom Lauerman at Penn State University, School of Visual Arts https://sova.psu.edu/ and is being developed in collaboration with Engineering Students as part of the University's Learning Factory program http://www.lf.psu.edu/ . The work is supported, in part, by Penn State’s Center for Innovative Material Processing through Direct Digital Deposition (CIMP-3D, http://www.cimp-3d.org ) This is only the print head portion of the design. An entire printer system is in active development and can be found here: https://github.com/Tom-Lauerman/Bricoleur . Please follow my newer clay printer developments here: https://plus.google.com/+TomLauerman For a complete parts list check the "Bill Of Materials" section. The print head costs about $30 USD to build (excluding printed parts). A recent video of the system in use can be found here: https://www.youtube.com/watch?v=JbxZZMp6b8A An older video of the whole system can be found here: https://youtu.be/X4ksTKWRqvM . A video of the print head working can be found here: https://youtu.be/533dqBrCdgo .