Which is the best format of CAD file to export model from Fusion 360 or SOLIDWORKS to Blender? ( is it .obj, .stl ,.step or other )
I want to Import a CAD file in Blender that I have created in Fusion 360 or SOLIDWORKS. For Maximum Compatibility and minimum chances of error.
Suggest to me the file format that I must use, is it?
Blender does not use B-Rep formats, so STEP (or IGES, Parasolid, etc.) is not an option. As Mechanical CAD does not use texture or similar, there won't be a difference in what you get whether you use OBJ or STL. OBJ will be generally slightly larger than a binary STL but smaller than an Ascii STL file. Not sure what Fusion/SW export by default, but in the end, based on your question, both STL and OBJ will give you the same (facet based) result in Blender. Going the other way though (Blender to SW/Fusion) is a different story...
See about settings in the application as that is where the level of detail is determined (number of points on a circle kind of thing)