You are totally right they can only be used on no mixed meshes. Check the source code modul https://github.com/FreeCAD/FreeCAD/blob ... shtools.py There I mixed shell mesh with face mesh and volume mesh. At time of writing the code years age I did not care but nowadasys it is cumbersome any time I read the code.HarryvL wrote: ↑Tue Apr 02, 2019 9:59 amHaving said all of that, it is not exactly clear what these descriptions are used for. A cable is a line element, but it can be embedded in a 1D, 2D or 3D finite element mesh. Similarly a plate or shell element can live in a 2D or 3D mesh, but a volume element can only live in a 3D finite element mesh. So what are we trying to name here?