Patternmakers in metal and plastic create the precise templates and molds that manufacturers use to produce metal castings and plastic parts. Working primarily in machine shops and foundry facilities, they study blueprints and technical drawings to understand exact specifications before using lathes, milling machines, grinders, and other precision equipment to shape patterns from wood, metal, or plastic materials. They carefully measure and fit pattern components together, ensuring tolerances are exact—sometimes within thousandths of an inch—since these patterns will be used repeatedly to create identical parts for engines, machinery, industrial equipment, and consumer products. The work requires meticulous attention to detail as they drill holes, cut grooves, and smooth surfaces to match engineering specifications. Patternmakers also construct core boxes, which form the hollow interior spaces in metal castings, and match plates that hold pattern halves together during the molding process. Success in this field requires strong mathematical skills, mechanical aptitude, spatial reasoning ability, and patience for exacting work. They typically work standard hours in manufacturing facilities, though the environment can be noisy with metal dust and chemical odors present despite ventilation systems.