Mesh settings not accessible in export

I converted a polysurface into a mesh inside Rhino, repaired the errors and now I have to export it to .stl. I can’t adjust mesh settings.

Hi - that is as expected. Those settings are only to create a mesh from NURBS surfaces. Once you have the mesh, it’s “fixed”. You could run ReduceMesh on a mesh to export, but that doesn’t give you the same controls, so that might, or might not, do what you want to achieve.

I have to adjust the mesh according to precise parameters for 3D printing

If I use for example “environment map” and adjust the mesh according to my preferences, then when I export the parameters will be those?

You do that during your “mesh conversion”. The .stl export after that will be identical - with the exception that any quad mesh faces will be triangulated - .stl does not support quads.

So if I understand correctly 1) I can set custom mesh parameters only when I convert a polysurface to mesh. 2) if I have a mesh (which took about 1 hour to be repaired manually (faces zero, faces duplicated, edges not manifold) that I had converted from an anurbs with parameters that do not fit me, I CANNOT change the mesh settings anymore. 3) to check the parameters of a mesh I can use “environment map”. Correct?


The custom mesh settings are available only to convert a polysurface to a mesh. You can do this:
1- Inside Rhino, before exporting like you did. This will allow you to manipulate/edit/repair the mesh before exporting to STL. Once you export to STL, the custom mesh settings in the STL export dialog are greyed out because it’s already a mesh that has been meshed with the parameters you needed.
2- At export, selecting the polysurface to export. Because STL doesn’t support polysurfaces, it will give you the option to make the custom mesh in the STL export options dialog. You can configure the mesh exactly as needed, but you won’t be able to check/edit/repair the mesh, as it will immediately be exported.

Scenario No 1 is probably the safest path. I’m not sure what you by No 3 but maybe I missed something along the way.

Hi Vanessa.
I got it. In scenario 3 I intended to understand if analyzing a mesh (which had previously been converted from a nurbs) with the command “environment map” the parameters I see on the monitor are the ones I used when converting from nurbs to mesh. Forgive my English.


Somewhat correct. When you create a mesh from a NURBS object in Rhino, the vertices are smoothed based on the NURBS object. That gives you the impression of a smooth object even if the mesh is just a bunch of flat triangles. When you 3D print the mesh, this smoothing will not be applied. To check mesh “quality” for printing, you might want to use the FlatShade command. Your printed object will look what you get on screen then.

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