The 4 Main Steps of the CNC Machining Process

Regardless of your CNC machining process, there are four basic steps to CNC machining. Below is a step-by-step procedure of how they typically work:

Step 1: Preparing a CAD Model

This involves creating a 2D or 3D model design of your product. There are a number of software packages that are suitable for this process, the popular ones being AutoCAD and SolidWorks, and it is also possible to convert a 2D design into a 3D design, depending on the requirements of the product.

Whilst some product designs may be simple, the preparation of some CAD models may require advanced knowledge, especially for complex product designs.

CAD models should be well designed and easily show operators key features such as tolerances, construction lines, threads and other parameters for efficient machining operations.

Step 2: Convert to CNC Compatible Format

CNC machines cannot understand CAD models. Therefore, you must convert the CAD model to a CNC-compatible format so that the machine can interpret it. For this step, you can use CAM software such as AutoCAD, Fusion 360 or other online software services.

This software converts to a CNC-compatible format and provides the CNC machine with parameters related to the machining operation, such as rotary and linear motion, cutting sequence, tool paths, workpiece, machine speed, and so on.

Step 3: Setup Execution

This involves selecting the correct type of CNC machine and configuring certain operations before the machining operation begins. Choosing the right machine depends on the workpiece, the complexity of the product design and the cost. Afterwards, the workpiece is mounted on the machine.

Step 4: Machining the Part

The operator will set up the necessary cutting tools and start the machining process. The machining process is automated and will run until the computer programme deems the machining complete. During and after machining, the machinist will perform multiple levels of inspection to ensure quality.