Faces, not facets
Welds the mesh, splits it into bodies and merges coplanar triangles into planar faces with real holes. T-junctions and doubled walls are repaired on the way. Each closed body becomes a MANIFOLD_SOLID_BREP.
PCB tools export STL: thousands of triangles, no faces, no holes, nothing to dimension. Board STEP Forge rebuilds real boundary geometry from that mesh and hands Fusion 360 a clean AP214 STEP, in millimetres, with one body per solid and faces you can sketch on.
Welds the mesh, splits it into bodies and merges coplanar triangles into planar faces with real holes. T-junctions and doubled walls are repaired on the way. Each closed body becomes a MANIFOLD_SOLID_BREP.
Facet fans are fitted with cylinders and cones by region growing on the mesh normals: holes, bosses, fillets, tapered walls and chamfers come back as one CYLINDRICAL_SURFACE or CONICAL_SURFACE with true arc edges, whatever way the mesher triangulated them. Real polygons stay flat, so a hexagon is still a hexagon.
Layers on a board, pads on a layer: where bodies share faces or edges, triangles are sorted radially around each shared edge and paired into separate closed shells. Overlapping flat extrusions are unioned into one prism.
Every body is accounted for. Whatever still cannot be closed is written as a surface body and flagged in the report, never dropped. Volumes and solid counts are shown so you can check before importing.