nThe nodes on solid elements only have translational DOF. There is no rotational DOF on a node connected to a solid element.nWhen you use Fixed Support on the face of a solid body, the nodes on that face are only getting XYZ translation set to 0. This is all that is needed.nIf you selected one straight edge on a solid body and applied Fixed Support, a Statics solution would fail, because there are no rotational DOF on the solid elements and holding just one straight edge creates a mechanism I would call a hinge, and that has no static solution.nShell elements have 6 DOF on their nodes, so if you mesh a surface and apply a fixed support to one straight edge of the surface, there is a static solution.n