Copyright Goodheart-Willcox Co., Inc. 24 CNC Manufacturing Technology a specific time period. In 2017, manufacturing alone accounted for over $2 trillion in US GDP. Manufacturing is responsible for nearly 12% of the total output of the United States. 2.2 Supplied Industries The manufacturing industry has massive impacts on national prosperity, individual workers, and any industry that uses machined parts, tools, or precision fits and tolerances. Nearly all industries rely on machinists. Some of the largest supplied industries include the automotive industry, medical technology, aerospace applications, defense, computing and technology, woodworking, and sheet metal fabrication. 2.2.1 Automotive Industry The automotive industry is probably the most recognizable manufactur- ing field. The historically powerful Detroit-based auto industry estab- lished the model for mass production, Figure 2-4. As you learned in Chapter 1, manufacturing existed long before Henry Ford, but the sheer number of parts required for the production and assembly of automobiles required an entirely different approach to machining. Modern cars have between 800 and 1,200 machined parts in the engine alone. As the auto industry grew so did the need for manufacturers across the country to begin building parts for cars. Although areas like Detroit have suffered in recent years from competitive automakers and offshore manufacturing, there are still machine shops across the country building pieces and parts for automobiles. 2.2.2 Medical Technology As the medical field has advanced and surgical tech- niques have become more technical, the need for high-precision components has increased. Current trends toward less invasive, outpatient procedures require devices to be much smaller and increasingly accurate. Many manufacturing jobs in this industry therefore require micromachining. Micromachining is the process of manufacturing extremely small parts, Figure 2-5. The types of parts made for the medical industry are as diverse as they are critical. Medical machinists work with a wide variety of materials, including titanium, stainless steels, cobalt chrome, aluminum, and even plastics and polymers. The earliest medical machin- ing primarily created tools such as forceps, clamps, or spreaders, but soon evolved into more advanced medi- cal devices, such as screws and plates to mend broken OVKNHR/Shutterstock.com Figure 2-4. Modern automotive assembly line. science photo/Shutterstock.com Figure 2-5. Micromachining of printed circuit boards for computer components.