When manufacturing product prototype is used to support product development, 3D printing and CNC (computer numerical control) milling machine are two prototype manufacturing processes that need to be considered. So how to choose between these two processes in specific applications, especially when the design and product specifications are not yet finalized? Combined with specific cases, we can understand the respective characteristics of the two processes.
Advantages of 3D printing process:
Complex geometry can be manufactured without the use of dies. It dose not affect time or cost. It allows users to quickly deliver small batches of parts, and it can flexibly and agilely adapt to design changes.
It supports parallel parts processing and saves time. Users can produce multiple parts in a single project, multiple versions of a single part, or multiple parts in different projects.
There is no need to use a variety of settings to manufacture parts, no need for operator supervision or intervention. After the start of the operation, the equipment will run until the parts are manufactured.
Examples of time and cost
The following example uses a labor cost rate of $37.00 per hour. For hourly machine time costs, these examples use a value of $1.00 for both 3D printing and CNC. For material costs based on extended volume calculations, 3D printing costs $1.00 per inch 3, while CNC costs $0.50 per inch 3**. (For example, portable pallets and industrial robotic adapters)
Materials. The 3D printing process as a whole can deal with a wide range of material categories, but each technology can only deal with one type of material, covering a small number of materials in the corresponding categories. CNC can process many kinds of materials, each of which contains many choices. The limitation lies only in whether the material is machinable.
2. Material properties. After CNC processing, the mechanical properties of the prototype are almost the same as that of the original material. After 3D printing, the performance of the prototype is similar to that of the original material. Consider also that because of the layered nature of the process, 3D printing parts are usually anisotropic.
3. CNC process tolerance is smaller.
The surface finish of CNC is better.
If only tolerance and smoothness are considered, CNC is undoubtedly the best choice. However, considering the comprehensive factors such as cost, manpower and delivery time, 3D printing technology has obvious advantages. Therefore, when you are using 3D printing technology, design considerations include:
Part Size and Order Quantity - Batch production of small parts is more economical.
Part size and design complexity - small and medium-sized parts with medium and high complexity are ideal.
Part Surface Area and Border Volume --- The larger the surface area per cubic inch, the more features it represents.
Fast and efficient product delivery
Make sure multiple design iterations are possible