3D printing and CNC machining, which is more suitable for prototype machining?

When manufacturing product prototypes to support product development, 3D printing and CNC machining are two prototyping machining processes to be considered. In specific applications, especially when the design and product specifications are not yet fixed, how to choose between these two processes? Let's analyze it from the aspect of quality:

1. Materials. The 3D printing process as a whole can handle a wide range of material categories, but each technology can only handle one type of material, covers a small number of materials in the corresponding categories. CNC machining can process a variety of materials, each of which contains many choices, limiting factors only in whether the material is machinable.

2. Material properties. After CNC machining, the mechanical properties of the prototype are almost the same as that of raw materials. After 3D printing, the performance of the prototype is similar to that of the raw material. What we also need to consider is because of the hierarchical nature of the process, 3D printing parts are usually anisotropic.

3. CNC machining process tolerances are smaller.

4. CNC machining has better surface finish.

If only tolerance and smoothness are considered, CNC machining is the best choice. However, considering the comprehensive factors of cost, manpower and delivery time, 3D printing technology has obvious advantages.