Many of the above problems stem from the fact that Blender is a mesh-type modelling program rather than a solids-based one like SolidWorks and FreeCAD. But for free-form or sculpted 3D objects ...

Probably the best free tool for our purposes is Blender, so that is what we shall ... and technically you refer to a single object like this as a ‘mesh’. You’ll also notice there are a ...