3D-Printable Enclosure: STL Checks and Assembly Fit (FreeCAD)

Independent FreeCAD enclosure sample prepared for 3D printing: separate base and lid with four alignment pins. - STEP, STL and native CAD exports. - Mesh checks: no open boundaries, non-manifold edges or winding conflicts. - Nominal assembly clearances of 0.25 mm radially and 0.30 mm axially, with no CAD interference. - Controlled open-mesh example showing regeneration from the retained CAD solid. Digital geometry checks only; no physical print or measured fit is claimed.