CNCs

CNC stands for computer numerical control. It refers to a class of manufacturing machines in which tool motions are directed by a computer using pre-programmed sequences of commands. CNC machines can perform operations such as milling, turning, drilling, routing, and cutting with high repeatability and accuracy. Common CNC machines include milling machines, lathes, routers, plasma cutters, laser cutters, and electrical discharge machines.

How CNC works: A CAD/CAM design is translated into a programming language such as G-code, which encodes axis movements, spindle speeds, feeds, and tool changes. The CNC controller reads the program and drives servo or stepper motors through motor drives to move the machine tools along one or more axes. Most machines support three linear axes, with four- and five-axis configurations available for more complex geometries. Automatic tool changers, precise encoders, and feedback systems enhance accuracy and repeatability.

Advantages and limitations: CNC offers high precision, repeatability, and the ability to produce complex geometries with reduced manual intervention. It enables automation, consistent part quality, and easier mass production. Limitations include high initial cost, specialized programming and setup requirements, ongoing maintenance, and the need for skilled operators and engineers to manage tools and cycles.

History and scope: CNC evolved from earlier numerical control systems developed in the mid-20th century and became widely adopted in manufacturing during the latter part of the century. Today, CNC remains central to modern fabrication, tooling, and metalworking, as well as certain nonmetallic material processes.