We look at what CNC programming is, what it is used for and its main applications when manufacturing parts by machining.

What is CNC programming?

CNC stands for Computer Numerical Control, which is a type of programming that creates instructions for a computer to control a machine or machining tool in an automated way.  The main characteristic of CNC machines is that they use software that runs lathes, milling machines, mills, laser cutters, etc. controlled by a machine or computer.

The main difference between CNC programming and conventional computer programming is that CNC programming sets operations defined at specific intervals and cycles using letters and numbers. As such, it is based on programming/controlling the movements that the machine performs by specifying the specific movement for each coordinate axis on CNC lathes, using the X, Y, on CNC milling machines for vertical movements, with the coordinates X,Y,Z, or on machines with more than seven axes.

There are two groups of information in a CNC program: technological data, which show functions that can be useful for the tool and the cutting conditions, and geometric data that have to do with the type of figure to be created on the part, its outline and dimensions, how it will be positioned to be able to work it efficiently, a description of the movements that the machine or tool needs to perform and the necessary reference points.

Types of CNC programming

There are two types of CNC programming:  manual, in which the tool works only with the reasoning and calculations performed by an operator, and computer-assisted, which performs the calculations necessary to control the machine with a computer.

Manual CNC programming

Manual CNC programming means that the part program is written with the calculations and reasoning performed by an operator. The operator is the one who sets the indicators that the tool must follow by entering the programs that the machine must perform on the control panel.

Manual CNC programming is very useful when the company manufactures simple parts in short series that do not require complex machining or when this programming is used together with other traditional machining processes. Although we can confirm that manual CNC programming is the most widely used, it is important to point out that, on some occasions, it is less productive than computer-assisted CNC programming as it does not always allow the next action to be ordered while the current one is being carried out.

Computer-assisted CNC programming

This type of programming is carried out automatically by the computer, which performs the calculations and dictates the steps for the machines to carry out their work on the parts. Computer-assisted CNC programming is a more automated and productive process than manual CNC programming and although it includes the programs by hand, it is carried out, as we said, with a computer and not from the machine’s control panel. 

  This is a more concise and modern type of programming that transmits information using wires or transfer devices with the help of CAD-CAM systems which help to manage large amounts of graphic information in the design of objects and also intervene in the programming of the machinery, helping to reduce the time in the exchange of series.  Thus, achieving high levels of automation saves time and improves productivity and process efficiency. 

Computer-aided CNC programming is used to produce and develop complex parts, in large series or when it is necessary to work with programs that need to be constantly modified. 

What software is used for CNC programming?

CNC machining software is the one that, through previous programming, is responsible for guiding and designing the movements that a machine must carry out. CAD, which stands for Computer-Aided Design, is the software used in CNC programming that creates and edits two- and three-dimensional models of physical objects. 

In addition, it is also important to understand that CAM, which stands for Computer-Aided Manufacturing, is responsible for making what has been designed effective. This software bridges CAD and helps to interpret these technical drawings by creating instructions to the machines to create the products. 

CAD/CAM has been used to simplify the machining process, achieving more precise finishes, saving time, greater safety, flexibility, as it allows variations to be made quickly, less waste of material, making it possible to make the raw material profitable by using only the right and necessary amount, and greater energy savings.

EONSI, CNC machining experts

EONSI can help you to get the best service in design and manufacture of parts or prototypes with CNC machines. We are experts in CNC machining and we guarantee the highest quality both in products made with manual CNC programming and in those that have been manufactured with computer-assisted CNC programming. Contact us and find out more about the advantages of manufacturing parts with CNC machining.