What is CNC Machining | CNC Machining Explained

You've probably heard someone mention CNC machining in passing if you're involved in manufacturing or if you're from Windsor-Essex County!


CNC machining or Computer Numerical Control machining is a process to manufacture products that uses preprogrammed computer software to control the movement of tools.


Though CNC machining was technically invented in 1751, with turning machines replacing handcrafted techniques, it wasn't widely used until the 1940s. This is when the first Numerical Control (NC) machines appeared. As the years progressed and computer technology advanced, NCs were replaced by CNCs. This allowed machinists to digitally control the machines they were tooling with rather than manually doing so.

Back in the day. a CNC machinist would consult blueprints for a part or component and determine the best way to machine the component based on the tools they have at their disposal. In recent years, this process has been computerized. A CNCist will use a 3D CAD model which they import into CAM programming software they will then create paths for the machine to follow by setting parameters in the CAM software which then in turn generates G-code. The CNC machine will then follow the paths laid out in the G-code and make cuts, drill etc. according to the instructions.


CNC machines are able to cut a wide variety of materials such as metal, paper, plastic, foam, glass, fiberglass, composites and most other things you can think of. To do this, there are carbide endmills that cut along specific trajectories. Think back to high school math, do you remember learning about the Cartesian Plane? Then you'll recall that there are 3 axes, X, Y & Z, that a 3D object can be mapped out on. A CNC machine will move it's drilling/cutting tool along these 3 axis to cut forward & backward, up & down, in & out. But that's not all! CNC machines can have up to 12 axis! The additional 9 are created by the ability to rotate the tools and the platform the material is clamped to at various points. .

Since a CNC machine is so versatile in the types of material it can work on, the kinds of products it can create are versatile as well. Here at DC Automotive Tooling, our CNC machines are generally used to create plastic injection molds out of steel, aluminium and other exotic metals.


Interested in becoming a CNC machinist? Check out our articles on CNC programmers and CNC operators to understand what each role entails and then feel free to apply via our Opportunities page!