What is a CNC machine?

A CNC machine is a computerised machine for machining mechanical work. The abbreviation CNC comes from the English term Computer Numerical Control. The term itself suggests the basic principle of how these machines work. It is therefore a computer with numerical methods. These are provided by dedicated software tools that control and monitor these machines and their key components. Servo or stepper motors take care of the movements of the tools. The basic electronic unit of the CNC machine is called the CNC Controller and can be understood as a kind of intermediate unit between the computer and the servo or stepper motors, which take care of the movements along all the defined axes of the CNC machine.

What is the working principle of a CNC machine?

The principle of operation for a CNC machine is the precise machining of the material, which is clamped by a clamping system that ensures that the material, or the object to be machined, is in a fixed position. The workpiece is positioned in a specific place and remains there until the end of the machining operation. Most often, it is sufficient for the CNC stand to vary the position of the tool along three basic axes, in the X, Y and Z directions. Of course, today there are very advanced CNC machines on the market that allow the tool to move in multiple axes, these can move in up to an incredible eight axes, and the most advanced machines can also move in more than eight directions, which must be supported by a CNC Controller. Unlike robots, which are also computer-controlled machines and are mainly used in production lines, CNC machines usually have the workpiece fixed in a chamber and the operator manually places and removes it from the machining area.

What are the main components for a CNC machine?

As mentioned earlier, the computer program is the basis for programming the CNC machine. CAD-CAM software tools are used to create the material processing plan. These drawings, with the plan, are converted into G-code which is understood by the CNC machine. The G-code gives the positions of the axes along which the machine head moves. Each line therefore tells us a new axis position of the machine. The M-code, on the other hand, defines the different functions that can relate to start, stop, feed speed, tool change, opening of the chamber door and so on. One of these CNC control software tools is Mach3, or even better, a more modern version of it. Mach4.

The next very important component is the mechanical structure of the machine. This is extremely important for high precision and robustness in the face of endless iterations of axis movements. In particular, the rigidity of the mechanical structure of the machine is important for accuracy and repeatability. Due to the high loads, CNC machines are mostly massive and heavy. Mechanical components need regular and careful maintenance for a long service life, at predefined time intervals adapted to the hours worked by the machine. Maintenance must also be carefully timed in production.

Source: http://www.woodfloorsinseattle.com/kaj-je-cnc-stroj-osnovne-informacije/