What's the difference between 3D printing technology and CNC?

First of all, let's take a look at the characteristics of hand-held proofing and CNC machining of 3D printing: the advantage of CNC is high efficiency and economy, while the advantage of 3D printing is super freedom, which can make geometric shapes that are difficult or impossible to realize by traditional processes (including CNC). Secondly, 3D printing technology, such as selective laser melting (SLM), needs a supporting structure in the implementation process. Without it, it can't be manufactured, which is also the bottleneck of its further development in manufacturing. Thirdly, the traditional NC machining industry has developed for a long time, and now there is a set of mature standards, whether it is spindle, tool interface or control system, but there is no such standard in the field of 3D printing at present, and the establishment of standards often takes a long time. 3D printing has a higher degree of freedom, and it can print all kinds of grotesque hand boards or product models, but the degree of freedom of NC machining has certain limitations. In a word, the sample range of 3D printing is larger than that of CNC, which is limited by the tool interface and smaller than that of 3D printing. One thing I haven't mentioned is that 3D printing is not as good as NC machining in printing whole parts, especially super-large parts. 3D printing is generally difficult to realize, but this problem does not exist in NC machining. CNC machining of hand-held samples is more advantageous than 3D printing in price. Because of the difference between the two, 3D printing allows you to process and display your imaginative works or products smoothly, while CNC has more advantages in economy and large-scale hand-made proofing. You can make a comprehensive comparison.