Machines and machine tools for treatment of materials and for additive manufacturing; 3D printers; 3D printer components of plastic and of metal for use in printing processes namely, heat sinks for use in machines, heat exchangers being parts of machines; Machine parts of 3D printers, namely, extruders and heated extruders, nozzles, heatsinks, cooling and heating systems primarily comprised of air-cooled heatsinks, radiative heatsinks, cooling fans, pumped water cooling in the nature of pumps for machines, thermoelectric peltier combined heating and cooling elements in the nature of heat pumps specially adapted for 3D printers, electrical resistance heating elements for heating metal objects and air heating specially adapted for 3D printers, electrical inductance heating elements specially adapted for 3D printers, infra-red radiation heating systems comprised of heat sinks for use in machines, heat exchangers being parts of machines; machine motors; motors for 3D printers; bearings as parts of machines; cartridge heaters being parts for 3D printers in the nature of heating elements specially adapted for 3D printers; structural parts and fittings for the aforementioned goods