Computer Numerical Control (CNC) machines are automated milling devices that make industrial components without direct human assistance. They use coded instructions that are sent to an internal computer, which allows factories to fabricate parts accurately and quickly. There are many different types of CNC machines, ranging from drills to plasmacutters, so they can be used to make a wide variety of parts. Though most are used industrially in manufacturing, there are also hobby versions of most of the machines that can be used in private homes.
Types of CNC Machines
The most common CNC machines are milling machines, lathes, and grinders. Milling machines automatically cut materials, including metal, using a cutting spindle, which can move to different positions and depths as directed by the computer instructions. Lathes use automated tools that spin to shape material. They're commonly used to make very detailed cuts in symmetrical pieces, like cones and cylinders.
Grinders use a spinning wheel to grind down materials, and mold metal or plastic into the desired shape. They're easy to program, so they're usually used for projects that do not require the same precision as mills or lathes. Besides these, there are also CNC routers, which are used to make cuts in a variety of materials; as well as computer programmable 3D printers; and turret punches, which are used to make holes in metal or plastic. This technology can also be used with different types of cutters, including those that work with water, lasers, and plasma.
Programming and Operation
The code used to program CNC units is generically called G-Code. It contains information about where parts of the machine should be positioned, and tells the machine exactly where to place a tool. Other instructions tell the machine additional details, like the speed a part should run at; how deep it should cut, burn, or punch; and the angle of an automated tool. Most modern industrial CNC machines are tied into a network of computers, and receive operating and tooling instructions via a software file.