Computer Numerical Control or CNC:

Computer Numerical Control or CNC is the designation of a machine that runs from the instructions feed to it via a computer controller. While the average person may have never heard of the term CNC, if you are working in the manufacturing industry, it's likely that you are exposed to it. CNC is used in a wide range of manufacturing processes today. Just to name a few, they are used to mill, drill, saw, grind, polish, turn, measure, assemble, draw, bend, punch, engrave, sew, tape, cut, glue, they are even used to load and unload parts to and from other CNC Machines. The picture to the right shows a CNC Robot doing just that with a CNC Turning Center.

CNC roots go back to the late 1940s. Later it was named NC for Numerical Control and the control received instructions from a pre-punched tape or card. In the 1960s a computer replaced the punched tape hence the designation Computer Numerical Control. In the 1970s machine tool manufacturers were in full swing building machine tools with CNC controls.

The Control or Controller:

The Control is the CNCs computer. For machine tools, the controller and other electronics are commonly built upon what was a conventional machine like a milling machine or lathe. This took the cranking of handles out of the picture. Complex profiled and contoured parts can now be very precisely machined in a much shorter timeframe.

The Axes:

All CNC machine types have at least two programmable directions of motion called axes. An axis can move along a straight line in which case it’s called a linear axis or rotate along a circular path in that case called a rotary axis. The more axes, the more complex the machine. Three linear axes machine tools and five axes machine tools with three linear axes and two rotary axes are common.

The Program:

A CNC program can be written manually but for more complex parts writing programs manually becomes much more difficult. To simplify the programming process, CAD/CAM software can be used with a common pc. The CAD (computer aided design) part of the software is used to draw the part. The CAM (computer aided manufacturing) part of the software is used to create the CNC program.

Need a job? People make a good wage and develop a rewarding career working with CNC machines. The industry uses people whom design, build, install, maintain, operate, program, and teach CNC.