SubD to Nurbs - Maintaining Surface Quality


I’ve been modeling in SubD and converting to Nurbs. Often when I do this conversion the smoothness of the surface is lost in some areas of the model, due to the complex web of spans Rhino generates. When looking in rendered mode the spans make the surface look like it has flutes that catch the highlights. To correct this I have to model new Nurbs surfaces in the high span areas. Does anyone have luck getting truly smooth SubD to Nurbs conversions, or is it common practice to have to make extensive nurbs surface repairs after the conversion procedure?

How much does it matter if you’re designing for materials that are not highly reflective, such as injection molded plastics?

Thank You,

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is it really distorted, or is the render mesh not dense enough to display smoothly? It’s easy to misjudge the surface quality if the render mesh is not clean.



Hi Kyle,

I tried upping the mesh to smooth and then spun the model around with a high gloss surface, see the attached images. I don’t know if it is actual surface discontinuity or just UI output.

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plastic.3dm (1.2 MB)

looks like render mesh settings here-

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@theoutside Looks great! Thank you Kyle.