EngATech Technical staff get asked about tips and “how to’s” regarding printing better parts on a regular basis, often enough in fact that we are hosting an October 20th webinar on the subject. But overall, there are some general tips that help customer achieve the best build for their application, but you have to start with a foundation. That foundation for 3D part design and build is the CAD file. And, most of the best practices involve getting your CAD file print ready. Here are a few areas to pay attention to:
CAD to STL file conversion – make sure that you save the file from the native format to a STL file in a high resolution mode. Usually in SolidWorks or Creo, there is a checkbox when you get ready to save that asks you to define the type of file and whether it is high resolution.
Save parts that have multiple areas with different material being printed in PolyJet digital format as an assembly file. If we can’t see where you want different materials printed into the file, it is difficult to define what goes where. We can import files as an assembly, but usually it is best to save as an assembly.
Triangles and resolution – if the part is coarse, the file will print out coarse with facets on curves and poor resolution in fine features.
Check files for errors such as inverted normal and open edges.
Fine features and walls thickness – in general, features below 0.020” should have special attention and you should talk to the service provider. On FDM parts, walls of that thickness may or may not be producible, depending on the machine used.
Currently several CAD providers are working with Stratasys to fully integrate the program into using 3D printers seamlessly from the design to the print. Work continues in this area and we monitor how customers are using this technology in the commercial marketplace. The two most notable providers are Creo and Autodesk, and now we are also seeing online Cad program such as TinkerCAD that allow you to develop designs without having to buy a seat of CAD software. We found the program to easy to use, and you can start with existing simple files and add to them to get even faster results.
And, in case you have a program that doesn’t save to STL format, there are several web based providers that will do this service. EngATech doesn’t have experience with these vendors, but the GrabCAD community forums and Thingiverse communities have users who can give you the pros and cons of several different programs.
Overall, we have just touched on a few areas that contribute to part robustness, and all the things that make 3D printing such an exciting area to explore.