Interesting printer. I am curious how the extruder and getting conrete too it works. Apparently for 9,000 in cash you can buy one. The software is “opensource” but nothing about the design.
One Man’s Journey To Build Portable Concrete 3D Printer Produces Its First Tiny House
http://concreteprinter.tumblr.com/
Buy here
http://www.vestaprinter.com/shop/160elzodc4lvwhxdp8g5lugyupyk93