What Is CNC Machining?
cnc machining is a production method that uses computers to control automated machines to make mechanical parts. It is a fast, reliable, and versatile manufacturing process that is used in industries like aerospace and automotive.
To use cnc machining, an engineer designs a product using a software program that then creates a 2D vector or 3D solid part CAD model of the product. This model is a computer-aided design (CAD) file that contains all the technical specifications needed to produce the product, including dimensions, tolerances, and construction lines. The CAD model can be created in-house by the engineering team or by an outside CAD/CAM design service.
After the CAD model is ready, a formatted digital programming code called G-code is generated from it by computer-aided machining (CAM) software. This code is then interpreted by the CNC machine to execute the machining process. The machine takes a block of material, called stock, and cuts away parts of it at high speed until it reaches the desired geometry of the product. The resulting pieces are then inspected to ensure that they meet quality standards and are ready for use or further post-processing.
While milling is the most common and popular machining process, other options exist for producing complex shapes. For example, some products require turning, in which a cylindrical stock is secured to a rotating mechanism and a cutting tool traces a profile on the stock at high speed, removing small amounts of material until it forms the shape of the final product.
Besides reducing lead time and cost, cnc machining also helps manufacturers produce parts that are more accurate. Because the machines receive precise instructions from a computer, they are able to produce parts with tighter tolerances and lower variation than manual machining. In addition, if there are any errors in the CAD model that cause the machine to produce inaccurate parts, the program can be corrected before further production runs.
CNC machining is especially helpful in producing precision parts that can be assembled into larger, more complex products. Because the parts are produced so accurately, they can fit together without any need for extensive fitting or adjustment. Additionally, if the CAM and CAD models are designed correctly, companion parts that were produced at the same time will match perfectly, further simplifying assembly.
The medical industry relies heavily on specialized and accurate CNC machinery. During the COVID-19 pandemic, for example, they needed to produce more and faster than ever before to keep up with demand for masks and respirators. This reliance on cnc machines helped them meet patient needs while keeping costs down.
However, while CNC machining is a powerful and efficient manufacturing method, there are limitations to its application. For example, it is difficult to use cnc machining on extremely hard materials or those that cannot tolerate heat. In such cases, water jet machining can be used as a coolant alternative to allow the CNC machine to cut through materials safely and precisely.