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"CNC" redirects here. For other uses, see CNC (disambiguation).
The examples andperspective in this article may not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page. (May 2011)
A CNC turning centerNumerical control (NC) is the automation of machine tools that are operated by abstractly programmed commands encoded on a storage medium, as opposed to controlled manually via handwheelsor levers, or mechanically automated via cams alone. The first NC machines were built in the 1940s and 1950s, based on existing tools that were modified with motors that moved thecontrols to follow points fed into the system on punched tape. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern computer numericalcontrol (CNC) machine tools that have revolutionized the machining processes.
In modern CNC systems, end-to-end component design is highly automated using computer-aided design (CAD)and computer-aided manufacturing (CAM) programs. The programs produce a computer file that is interpreted to extract the commands needed to operate a particular machine via apostprocessor, and then loaded into the CNC machines for production. Since any particular component might require the use of a number of different tools – drills, saws, etc., modern machines oftencombine multiple tools into a single "cell". In other cases, a number of different machines are used with an external controller and human or robotic operators that move the componentfrom machine to machine. In either case, the complex series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD design.