The STL file format is ubiquitous for 3D printing in its various forms, however it is not perfect. Many users will run into scaling issues or have to convert units while setting up their printers for printing. These problems can lead to a variety of issues sending files to slicer software that can then lead to significant amounts of extra time processing the STL files to prepare them for printing. This is primarily because an STL file doesn’t contain significant amounts of information about the model and stores the information in a very large file. However more modern 3MF files contain significantly more information about the model and stores the model data in a natively compressed format resulting in a much smaller file size.
STL Files (Stereo-Lithography)
The STL file format was created back in the 80s when 3D printing was first being invented, 3DSystems needed a new file format to store the model data in that could then be translated into usable machining code. They created the STL file format, to store essentially raw triangular data, color and other needed model information. This format worked while models were fairly simple and was adopted by most hardware and software manufactures as a common format. As models have become more and more complex quality expectations have increased and while a higher resolution print can be obtained through smaller triangles, it is reaching its limit while producing very large files.
3MF Files (3D Manufacturing)
This modern file format utilizes standardized methods to include greater information in a smaller for file size for 3D printing and many other additive manufacturing practices. While most other formats have been introduced by various manufactures 3MF is the only format introduced and maintained by an industry consortium, this means that the standard was quickly adopted is being maintained to high quality standards along with being expected to become the boarder standard in the coming years. The 3MF format has been adopted by all of the major and secondary tier hardware manufactures world wide with all of their machines supporting the full information format of the standard.
Switching from STL to 3MF functional doesn’t change anything on the export from your CAD/modeling software, the process will still be the same, you simply choose a different format. There additionally should be little difference once you import into your slicer software. The primary difference is that in your slicer software you will have more information to work to properly scale and slice your model accurately. This can save a significant amount of time in your post-processing and give your better results in your finished product.