In 3-D printing, the object is laid down one thin layer at a time. I’m not sure how the moving parts are made—maybe of a different material that does not stick to the other parts.
Pretty cool technology. Maybe when it becomes possible for anyone to print their own guns, the gun control nuts will turn their attention to the real problem of mental illness.
I want a 3-D printer to make models of biological molecules. But that’s just because I’m a biotechno geek.
They make several of the needed moving parts, including what appear to be springs, out of plastic also. It appears from the pictures on the website one part is metal.