On file 04-29b, Thickness works well: It is a boat Body with longitudinal symmetry. On PartDesign WB, it is made by lofting through 3 sketches. The sketches are on the same XZ plane but displaced by Y ...
PartDesign Thickness tool offers the selection of three modes, only one of which (Skin) works. The Pipe and Recto Verso modes are not implemented and thus do nothing. What's more, the Intersection ...