What is the difference between CNC milling and CNC turning?

CNC milling and CNC turning are two common methods used in CNC machining. Both are used to ensure that a component has the correct dimensions and shape, often as one of the final stages in the manufacturing process.

The main difference is which part is moving. In milling, the tool rotates, whilst in turning, the workpiece rotates.

In milling, it is the tool that rotates

At CNC milling The workpiece is held in place whilst a rotating tool works on the material. The tool can move in several directions and machine the workpiece from different angles.

This makes milling a flexible process. The method is used to machine flat surfaces, edges, grooves and holes.

In turning, it is the workpiece that rotates

At CNC turning Instead, it is the component that rotates. A tool is moved towards the material and shapes the component as it rotates.

As the workpiece rotates around its own axis, the result is a round shape. Turning is therefore mainly used for round and cylindrical parts.

The shape of the part determines which method is suitable

The choice between milling and turning is primarily determined by the shape of the component. Put simply, it usually works like this:

• Flat surfaces and angular shapes – milling
• Grooves, recesses and holes – milling
• Shafts, pins and bushings – turning
• Round workpieces that require a precise diameter – turning

As the client, you do not need to choose the method yourself. The drawing usually specifies which surfaces are to be treated and how.

There are many details that both need to be considered

Not all components fit into just one category. A component may have a rounded section that needs to be turned, whilst also having flat surfaces or holes that need to be milled.

In such cases, the methods are combined. This is common for parts that are to be fitted to other components, where both the fit and the fastening must be correct.

The difference lies in the movement and the shape of the details

In milling, the tool rotates, whilst in turning, the workpiece rotates. Milling is therefore used for flat and angular shapes, and turning for round ones. The method required depends on the design of the workpiece, and both are often used.

Do you need help with CNC machining?

At Linde Maskiner, we specialise in both milling and turning. Whether a component requires one method or both, we tailor the machining process to the drawings and specifications. Contact us today, and we will help you further.