O.k, I've tried RapidForm/Polyworks/Geomagic and everything in between. I do this for a living. Every project is different, so no one solution works all the time, but here is my input:
Please keep in mind, scanned surfaces/point clouds and NURBS/CAD surfaces are different. Meshlab is a useful tool for scanned surfaces. There are no free resources for NURBS/CAD surfaces that I have found.
To generate surfaces for machining/CAD:
Free solution 1: Use free Rhino3D trial (25 free saves) to generate NURBS surface patches. You have to trace over the mesh or you can drape a patch (like a cloth) over the surface. You can also buy Rhino outright; it's cheap, powerful, and can do a lot (but not all) scan-to-NURBS translations.
Free solution 2: To create CNC toolpaths straight from scanned meshes, use FreeMill. Easy, free, but limited options.
Purchase option 1: Buy Leios surfacing/patching license. Definitely the most cost effective tool to get to CAD/NURBS surfaces. The Autosurfacing tool is easy, and can generate surfaces for CNC machining without any brainpower.
Purchase option 2: Buy RapidForm. It'l cost you a fortune, but it has the best package for reverse engineering mechanical parts and parametric solids. Basically a good fit for recreating parts, as opposed to statues and carvings.
Or contact me directly, and I can convert for you.
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