Invisible nurbs polysurf

I have some polysurfs that refuse to render in Thea. They are not blocks, are not bad surfs, and have had a number of rendering material assignments but never are seen in a rendering. I have copied them and opened in a new file, exploded them, untrimmed them, reversed the normal direction and still not to be seen. This is using Thea and the window display mode for Thea (Presto I think). I can extract the rendermesh and then those can be rendered but I don’t usually do that and prefer to keep them as NURBS. For now I am extracting the rendermeshs for that purpose and hiding the NURBS originals but that just adds to a huge model. Any ideas?

Help! Is anyone out there?

@Joseph_Culbert, can you post the geometry ?


Clement! Someone heard. Yes I can do so, it is a real quandry and if that helps I will post the offending polysurf. Seems like there are more showing up in that copied document which may indicate something wrong with my tolerances. Let me see if that is what it is and I’ll round up the whole herd of offending polysurf and post if that doesn’t work.