Convert STL to IGES Solid

I have an existing STL model that now needs to become a true solid body so my machining vendor can load it straight into their CAM software. Please take the mesh and rebuild it as a clean, fully-closed IGES solid. Accuracy is important because the file will drive manufacturing directly; tolerances must match the original STL within typical machining limits. Main deliverable • One IGES / xt/ file that opens as a single watertight solid, ready for tool-path generation. If you spot obvious mesh defects or areas that will cause problems on the shop floor, flag them and let me know—we can agree on any quick touch-ups before finalising. Native CAD work may have been done in SolidWorks or similar, so as long as the IGES imports cleanly there, we are good. Let me know your lead time and anything you need from me beyond the STL.