Convert Mesh to Precise Solid

I have a faceted mesh that I can supply as a STEP file. It represents a rubber part I captured in Fusion 360 by scanning, sketching cross-sections and lofting, then switching to mesh so I could apply smoothing (and scale to 0.95). The result looks good, but my tooling manufacturer will only accept a true solid (B-rep) they can machine or modify.

I therefore need the mesh reverse-engineered into a clean, watertight solid that matches the current geometry exactly—surface quality and dimensions must stay true, as high accuracy is essential for injection-mould tooling.

If you can achieve this, you’re free to work in Fusion 360 (preferred) or another professional CAD package such as SolidWorks, Rhino or AutoCAD, provided the final deliverable comes back to me as a fully editable solid (STEP or native Fusion archive).

Key acceptance criteria:
• Surfaces remain as smooth as the supplied mesh—no visible faceting or loft steps.
• Topology is a single, manifold solid with correct face normals and no self-intersections.
• Dimensions line up with the existing model; I will run a deviation analysis and expect it to fall within ±0.1 mm over the part.

I’ll send the STEP mesh and any reference screenshots once we start. Let me know your proposed workflow and typical turnaround so we can get this ready for the toolmaker right away.

Will need to sign a NDA and IP will belong to me.