Machine automation isn’t a recent idea. In the 1800s, cam-driven automatic lathes and screw machines were created. In the first half of the 1900s, manufacturing equipment began to use numeric control with punched cards and tape to guide drilling and cutting. The rise of cheaper computer technology in the late 1960s and early 1970s brought about computer numeric control, or CNC machines. Instead of using punched cards or tape to operate the machine, commands are now programmed directly into the computer.
Motion
Almost all CNC machines use the same 3-axis system or a variation of it. There is a table that can move along the X-axis, back and forth, and the Y-axis, side to side. The tool arm moves up and down on the Z-axis. The table positions the workpiece at certain points on the X- or Y-axis, while the tool arm applies the drill, for instance, to a specific depth. More advanced machines may also use an A-axis, B-axis, or C-axis, which refer to rotational movements around the X-axis, Y-axis, and Z-axis, respectively.
Programming
Like any computer driven system, CNC machinery requires a program in order to function. In essence, these programs are little more than a series of commands that tell the machine when and where to move the table, apply the tool arm, or both. These programs can be developed manually, but contemporary CNC machinery is usually designed to work with computer-aided manufacturing (CAM) programs that generate CNC programs the machinery can interpret. Ideally, transfer of the program happens over a distributive numerical control or DNC system, which is a network of CNC machinery and a computer. In the absence of a DNC system, the program can be input manually or via a flash drive.
Applications
A wide variety of industries employ CNC machinery as a basic element in their manufacturing. The metal milling and metal fabrication industries rely on CNC for parts production. Electronics manufacturers employ it to solder circuit boards. Wood furniture manufacturers use CNC lathes for drilling and the production of identical components, such as table legs. Even some types of engraving work are performed using CNC.
Benefits
CNC machinery offers a number of benefits. It enhances the accuracy of the work, which can be critical in industries where tolerances are measured in ten-thousandths of an inch. It limits worker exposure to particularly dangerous manufacturing processes. It reduces waste by limiting the number of flawed workpieces and it enhances efficiency. With regular maintenance and barring a mechanical failure, CNC machinery will continue to produce at the same pace indefinitely.