CNC machining is the manufacture and processing of parts and products under computer control.
Numerical control machining involves the use of computer numerical control (CNC) machines to shape and resize a piece of material, known as a work piece, by automatically removing the material. Usually, the material used is plastic or metal, and when the removal is complete, the finished product or product is already produced.
This process is also known as subtraction manufacturing. For CNC machining, computer applications are used to control the movement of machine tools.
Common types of CNC machine tools
CNC machining processes include the most common milling and turning, followed by grinding, electric discharge machining and so on.
Milling is the application of a rotary tool to the workpiece surface, moving along 3, 4, or 5 axes. Milling is basically the cutting or trimming of a work piece, allowing for the rapid processing of complex geometric shapes and precision parts from metal or thermoplastics.
Turning is the use of a lathe to make parts containing cylindrical features. The workpiece rotates on a shaft and comes into contact with a precision turning tool to form circular edges, radial and axial holes, slots and grooves.
Advantages of CNC machining
Compared with traditional manual machining, CNC machining speed is much faster. As long as the computer code is correct, and in line with the design, the finished product dimensional accuracy is very high, little error.
Numerical control manufacturing is an ideal rapid prototyping manufacturing method. It can also be used to manufacture end-use products and components, but is usually only cost-effective during short production runs in low batches.
Multi-axis CNC machining
CNC milling involves removing material using a rotary cutter. Either the workpiece remains stationary and the tool moves onto the workpiece, or the workpiece enters the machine at a predetermined Angle. The more axes of motion a machine has, the more complex and faster its shaping process becomes.
3-axis CNC machining (3-axis CNC machining)
Three-axis CNC milling is still one of the most popular and widely used machining processes. In 3-axis machining, the workpiece remains fixed and the rotary tool cuts along the x, y, and z axes. This is a relatively simple form of NC machining that can produce products with simple structures. It is not suitable for processing complex geometric shapes or products with complex components.
Since cuts can only be made on three axes, the machining speed may also be slower than four - or five-axis CNC, as the workpiece may have to be manually repositioned to get the desired shape.
4-axis CNC machining (4-axis CNC machining)
In four-axis CNC milling, the fourth axis is added to the motion of the cutting tool, allowing rotation about the X-axis. Now there are four axes - x, y, z and a (rotating about the x axis). Most four-axis CNC machines also allow the workpiece to rotate, which is called the B-axis, so that the machine can act as both a milling machine and a lathe.
If you need to drill a hole into the side of a part or the curved surface of a cylinder, 4-axis CNC machining is the way to go. It greatly speeds up the processing process and has high machining accuracy.
5-axis CNC machining (5-axis CNC machining)
Five-axis CNC milling has an extra axis of rotation compared to four-axis CNC. The fifth axis is rotation about the Y-axis, also known as the B-axis. The workpiece can also be rotated on some machines, sometimes referred to as the b or c axis.
Because of its high universality, 5-axis CNC machining is used to manufacture complex precision parts. Such as medical parts for artificial limbs or bones, aerospace parts, titanium parts, oil and gas machinery parts, military products, etc.