An In-Depth Look at How CNC Machining Works

CNC machining, or Computer Numerical Control machining, is a complicated process. In this article, we hope to de-mystify CNC machining so that companies - like yours - can decide if custom tooling and custom machining is right for you.

CNC always begins with custom product design. Companies come to NTG Tool with custom product design questions. Sometimes, an NTG client has already identified and designed the products that they need to be created with a VMC/CNC mill, but often, we consult on custom product design and work with product developers to identify useful solutions for their custom tooling issues.

Once the needs of the NTG client have been identified, we set to work designing the product or part with a CAD tool. CAD tools are a software pioneered in the 1960s. They are used to create three dimensional models, and their use applies to many industries outside of custom tooling and custom product design - namely, in architecture! The CAD 3D model data is converted into CAM data - which stands for Computer Aided Machining or Computer Aided Manufacturing.

*A 3D representation of the product, created with CAD tools.*

Now that the custom product design needs have been identified, and the custom tooling part has been created virtually, it's time for the custom machining. An NTG specialist will help you identify the best method for creating your project, as there are many options including waterjet technology, wire EDM cutting, and use of a VMC/CNC mill. These mills are very large and intricate. They make use of at least three rotary axes - X, Y, and X - and these axes all have the capability to cut the raw material at very precise angles. Some CNC mills even have 5 axes for incredibly detailed and precise cutting.

So: the custom product design specifications have been created, modeled in a virtual environment with a CAD tool, and then turned into coded "instructions" for the CNC mill or VNC mill. Then, the raw material is loaded onto the cutting surface. The machine knows what to do - and then, the magic begins.

There are different ways that the cutting actually takes place. One of them is through the use of drills. Drills work by spinning a drill bit against stationary raw material, or stock. We also use lathes to do our cutting. Lathes work by rotating the raw material against a stationary drill bit or cutter to remove excess material in a circular or fluid path - kind of like drilling, but in reverse. Lastly, the most common CNC machine type is milling. Milling uses rotary cutting tools to remove material from a stock piece. They work similar to drills, but they have a lot more flexibility and variety of uses.

Custom machining often uses metal raw material to create a final product, but many raw materials can be used including wood and plastic. For most industrial use, however, metal is the preferred material.

We hope this has been an informative peek into our world. If you have any questions about what we do, how we do it, and how we can help you with custom product design and custom tooling, please give us a call or use our contact form on our webpage.