Is there any interest in hearing about Inkjet printers that used "hot-melt' materials to print three-dimensional or "raised features" on surfaces? Making models requires an ink with some thickness, a CAD design with some Z dimension and a printer that can allow the inks to pile up in the Z axis to make an object that someone can pickup and see. Jetting, extruding and UV curing of materials were early technologies that were used to make thick layers. First to appear were the inkjet inks that had some thickness when placed on a surface. These substances could be overlaid to make a thicker model but no overhangs would be supported. The early layers needed to have controlled thickness and so a CAD file with uniform Z axis dimensions was introduced sometime in the late 1980's. Support structures had to be added to these early CAD files by designers since the machines did not have these features. A support structure patent was introduced in 1992. The first printer with built in support appeared in 1994 and could be called the first real 3D model printer.
Inkjet introduced hot-melt wax inks in 1963 and hot-melt liquid metal alloys in 1971. Inkjet with solid color inks was not introduced until 1985 and led to the Inkjet 3D Support patent in 1992. These solid color inks were used in that first desktop 3D printer used by jewelers and it is still in production today. Inkjet technology has been ahead of all other technologies from the early days printing. A collection of these printers and their stories is in the making and I am looking for questions about inkjet printing.