What is the difference between 3D printing and CNC?

2023-12-13 11:05:44

When quoting a prototype project, it is necessary to select an appropriate processing method for the characteristics of the parts in order to complete the prototype project faster and better. At present, there are mainly CNC Machining, 3D printing, laminating, rapid mold and so on. Today we will talk about the difference between CNC machining and 3D printing.

First of all, 3D printing is the 1 additive technology, and CNC machining is the 1 subtractive technology, so they are very different in terms of materials.

1. Differences in materials

3D printing materials are mainly liquid resin (SLA), nylon powder (SLS), metal powder (SLM), gypsum powder (full color printing), sandstone powder (full color printing), wire (DFM), sheet (LOM) and so on. Liquid resins, nylon powders and metal powders account for the vast majority of the industrial 3D printing market.

The materials used for CNC machining are all plates, that is, plate-shaped materials. By measuring the length, width and height loss of parts, the plates of corresponding sizes are cut for processing. CNC machining material selection than 3D printing, general hardware and plastic plates can be CNC machining, and the density of molded parts is better than 3D printing.

2. Parts difference due to forming principle

As we mentioned earlier, 3D printing is the 1 kind of additive manufacturing. Its principle is to cut the model into N layers/N points, and then stack them one by one/1.1 points in sequence, just like building blocks. Therefore, 3D printing can effectively process and produce parts with complex structures, such as hollow parts, while CNC is difficult to process hollow parts.

CNC machining is subtractive manufacturing, through high-speed operation of a variety of tools, in accordance with the programming of the knife to cut out the required parts. Therefore, CNC machining can only process rounded corners with a certain radian, but cannot directly process the inner right angle, which should be realized by wire cutting/spark and other processes. Outside right angle CNC machining is no problem. Therefore, parts with inner right angles can be considered for 3D printing and processing.

There is also the curved surface. If the area of the curved surface of the part is relatively large, 3D printing is also recommended. CNC machining the curved surface is time-consuming, and if the programming and operation master is not experienced enough, it is easy to leave obvious lines on the parts.

3. Differences in operating software

Most of the 3D printing slicing software is simple to operate, even laymen can skillfully operate the slicing software in a day or two under professional guidance. Because the slicing software is currently optimized very simply, the support can be automatically generated, which is why 3D printing can be popularized to individual users.

CNC Programming software is much more complex, all need professionals to operate, zero-based people generally have to learn about half a year. In addition, 1 CNC operator is needed to operate the CNC machine.

Because the programming is very complicated, a part can have many kinds of CNC processing scheme, and 3D printing will only have a small part of the influence on the processing time and consumables because of the placement position, which is relatively objective.

4. Differences in post-processing

There are not many options for post-processing of 3D printed parts, usually polishing, oil injection, deburring, dyeing, etc.

The CNC Machining Parts after-treatment options are varied, in addition to polishing, oil injection, deburring, electroplating, silk screen printing, pad printing, metal oxidation, laser engraving, sandblasting, etc.

There is a sequence of hearing and a specialization in technical fields. CNC machining and 3D printing have their own advantages and disadvantages. Choosing the right processing technology plays a vital role in your project. Choose Qi Le, our engineers will analyze and suggest your project.