CNC

CNC stands for computer numerical control, a method of automating machine tools through programmed instructions. CNC systems control movements of tools along multiple axes to perform milling, turning, drilling, and cutting with high precision and repeatability. The approach evolved from early numerically controlled machines in the 1940s–1950s and gained prominence with the integration of computer technology in the 1960s and 1970s.

A CNC system typically comprises a machine tool (such as a milling or turning center), a CNC controller, servo or stepper drives, feedback devices (encoders or scales), and an interface for programming input. The controller reads coded instructions and converts them into axis motions and spindle speeds. Most machines use multi-axis configurations from three to five or more axes.

Programming is usually done with G-code, an industry-standard language that directs tool movement and machine functions, and can be generated from computer-aided design/manufacturing (CAD/CAM) software. Programs specify geometry, speeds, feeds, and tool changes. Many advanced CNC systems support canned cycles, subroutines, and adaptive or responsive control.

Benefits include high precision, repeatability, automation of repetitive tasks, and the ability to produce complex geometries. Limitations include high initial cost, programming and maintenance requirements, and the need for skilled operators. Machines also require safety measures to guard against moving parts and chip generation.

CNC is used across manufacturing sectors, including automotive, aerospace, electronics, and medical devices. Standards such as ISO 6983 govern the syntax and semantics of numerical control programming in many regions, while G-code (RS-274NGC) remains the de facto language for many machines. The integration with CAD/CAM and data analytics is expanding capabilities and efficiency.