a method of processing metal , metallic alloys , and metal matrix composites in a plastics injection molding machine is disclosed . the method includes the steps of providing a plastics injection molding machine having a screw . a step of removing the screw is included in the method . a step of replacing the screw with a modified screw configured and arranged for processing metals is also included . alternatively , a step of removing the flights from the middle portion of the original screw shaft may be included .