This article will cover some CAD programs, such as Blender, FreeCAD, SketchUp. They are not the best choice for fully fledged STL editing due to some differences in the way they represent some shapes. They weren't originally developed with 3D printing in mind, although they are pretty useful for this workflow. These programs aim for covering engineering and construction modeling purposes, providing precise measurements and solid modeling tools. There are two types of programs that allow users to edit STL files: There are STL editors that help users with that. In other cases, you would need to edit or repair it. Sometimes, the pre-downloaded STL file or your own model is good enough.
At some point any 3D printing hobbyist will wonder how to edit STL files.
