ome time ago Stratasys advanced and patented 3d printing. The orginal offerings were in the thousands of dollars. Hackers started making machines for their own use. Eventually the patents ran out and Asian manufacturers started developing hobby and enthusiast level machines.  The early machines were limited in what materials they could handle but enthusiasm prevailed and heated beds and self leveling capabilities found their way into very economic machines capable of producing products of enviable quality using literally a variety of 100s of material formulas in a wide assortment of colors.