In modern manufacturing, CNC machining and additive processes are two important processing technologies, each with unique advantages. However, CNC machining shows significant advantages in many aspects compared to additive processes. CNC machining has become the first choice for many industrial applications due to its excellent precision, diverse material selection, excellent surface finish and efficient mass production capabilities. Especially in manufacturing environments that require high precision and consistency, CNC machining has shown its irreplaceable advantages.
What is CNC machining? Additive process?
CNC processing (Computer Numerical Control) is an automated machining technology controlled by a computer. It uses computer programs to control machine tools to perform cutting, milling, drilling and other processing operations to manufacture parts with complex shapes and high precision. CNC processing is widely used in the processing of metal, plastic, wood and other materials.
Additive Manufacturing, also known as 3D printing, is a technology that creates three-dimensional objects by adding materials layer by layer. Unlike traditional subtractive machining, such as CNC machining, additive processes build objects by incrementally adding material, rather than removing material from raw materials.
Advantages
1.Processing accuracy and stability
CNC machining is known for its high precision and stability, especially when manufacturing complex parts. CNC machining removes material through cutting, milling, drilling, etc. to achieve precise geometry and dimensional control. In contrast, additive processes often rely on stacking materials layer by layer, which is less precise and prone to errors, especially when processing very fine details.
Case: An aerospace company needs to manufacture a high-precision turbine blade with a very complex geometry and extremely high accuracy requirements. After comparison, the company chose CNC processing technology. The high precision and repeatability of CNC machine tools ensure that the dimensions of each blade are exactly as designed, while additive processes cannot manufacture these parts with such high precision.
2.Diversity of material selection
CNC machining is suitable for a wide range of materials, including metals (such as steel, aluminum, titanium, etc.), plastics, wood, composite materials, and more. This enables CNC machining to meet various industrial needs, especially in the processing of high-strength, high-durability materials, where CNC machining excels. The material selection for additive processes is relatively limited, especially in the application of high-strength materials.
Case: A medical equipment manufacturer needs to produce a batch of high-strength, stainless steel casings that are corrosion-resistant and wear-resistant. Due to the limitations of additive technology in processing high-strength stainless steel, CNC processing was finally chosen. This ensures not only the strength and performance of the material, but also the long service life of the housing.
3.Surface finish and post-processing requirements
CNC machining produces high-quality surface finishes directly, often without the need for complex post-processing steps. By using high-quality cutting tools and precise machining paths, CNC machines can achieve extremely smooth surfaces. This is critical for certain parts that require a high surface finish. The additive process usually produces a rougher surface, which requires additional post-processing such as grinding and polishing.
Case: An automotive parts supplier needed to produce an engine block that required smooth surfaces and tight tolerances. Through CNC machining, they are able to directly obtain the required smooth surface without additional post-processing procedures, which greatly improves production efficiency and reduces costs.
4.Efficiency of mass production
CNC machining excels in mass production, especially when producing multiple parts of the same design. CNC machines are able to maintain consistent high precision and efficiency. In contrast, additive processes are generally suitable for low-volume or customized production, and when high-volume production is required, additive processes are often not as time- and cost-effective as CNC machining.
Case: An electronic product manufacturer needs to produce a batch of aluminum heat sinks. Each heat sink has the same design and requires high production efficiency and consistency. Through CNC machining, the company is able to produce these heat sinks in large quantities in a short time and ensure that each part is consistent in size and performance. This high-volume production capability gives CNC machining a huge advantage in efficient production.
5.Ability to process complex geometric shapes
While additive processes are best known for their ability to create complex geometries, CNC machining still excels in certain situations. Especially when processing parts with internal channels, complex curved surfaces or other precision structures, CNC machining can achieve high-complexity processing through multi-axis linkage technology, while additive processes are sometimes difficult to achieve the same complexity and precision.
Case: A pharmaceutical equipment manufacturer needs to produce a special mixer with a complex internal structure that contains multiple curved surfaces and precision channels. The company successfully manufactured this complex part through five-axis CNC machining, ensuring its efficiency and stability during the production process. However, additive processes have greater challenges in handling these precision channels.
6.Processing speed and cost effectiveness
CNC machining generally has faster processing speeds, especially when processing metal materials. Additive processes are generally slow in the material stacking process, especially when manufacturing large parts, and the time cost is high. In addition, the raw material utilization rate of CNC machining is usually higher, and waste disposal is relatively simple, further reducing production costs.
Case: An energy equipment company needs to produce a batch of large aluminum parts that are used in wind power equipment. Due to the large size and large quantity of parts, CNC machining is the optimal choice due to its high speed and efficient material utilization. This not only shortens delivery time, but also greatly reduces production costs, allowing the company to maintain an advantage in market competition.
7.Production consistency and quality control
CNC machining excels in production consistency and quality control, especially in high-volume production. CNC machine tools are controlled by computers, and the production process of each part is completely consistent, ensuring product consistency. Due to the different ways of stacking materials in the additive process, there may be slight differences between different parts, affecting consistency.
Case: A consumer electronics manufacturer needs to produce the casing of a new smart watch. Each casing is required to be exactly the same size and appearance to ensure a high-quality image of the product. Through CNC processing, they are able to produce parts with extremely high consistency without having to worry about differences between products, which greatly enhances the brand’s market competitiveness.
Conclusion
CNC machining has significant advantages over additive processes in many aspects, including high precision, diverse material options, excellent surface finishes, batch production efficiency, the ability to process complex geometries, machining speed and cost-effectiveness, and consistent production performance and quality control, etc. These advantages make CNC processing still occupy an important position in modern manufacturing. Especially in scenarios that require high-quality and high-efficiency production, CNC processing is still the technology of choice for many industries. By combining specific cases, we can see the breadth and importance of CNC processing in practical applications, providing manufacturers with reliable technical support.