Trouble importing file from rhino5

I am trying to import a rhino5 file formatted in .3dm. I get an error message saying no mesh data was read- please ensure the data has render meshes at a suitable resolution stored in the file.

The rhino model is good- no naked edges etc. Where do I go from here?


By the sounds of it, you can open the file and all is good but you have problems importing it.

Are you importing a Rhino file into Rhino? And is it Rhino that is giving you the error message? At what point do you get that message?

Sorry. No I am importing the file into another cad program (Aspire) which runs our CNC machine.) Apparently the file was written in AutoCAD, sent to a middle man how opened it in Rhino and forwarded it to me. Thanks for any ideas.

You either need the middle man to create a mesh from the object(s) that are in the file (which most likely is as simple as extracting the render mesh) or you can download a trial of Rhino and see if you can do that yourself. That way you would also have control over the ‘quality’ of the mesh - tweak parameters if you find that what’s in the file is too rough, for example.

[or, you could send the file here and somebody will do it for you :wink:]

Thanks for the offer.

To be honest I’m a bit out of my depth in the areas you are describing so here is the file I am working with and I’d like to have it as a useable .3dm file.

Thanks for anything you are able to do.

KEEL REV G.3dm (1.0 MB)

See attached file.
I’ve extracted the render mesh and put that on a new layer called Mesh. Please check if Aspire can do something with this. KEEL REV G-RenderMesh.3dm (2.0 MB)

Note that there were 3 closed objects in the file and as such there are now 3 meshes. Let me know if that is as intended.

Hi wim, The file is now fully functional in Aspire. Thanks very much.

If it is not too much to ask, how exactly did you ‘extract the render mesh’ and what does this mean. I assumed that any model would come with its “mesh” being a key component of the file. I also assumed that to export a model in .3dm which is compatible with Aspire that whatever conversions might be required (ie. Nurbs to triangular mesh) had been done.

Again, thanks for your help. It has made a big difference.



The quick answer is that I probably / likely / possibly didn’t have to do anything else than just putting Rhino in a shaded mode, save the file, and upload again. But since I don’t have Aspire, I couldn’t check that to be sure.

Anyway, a surface in the NURBS format is just a mathematical representation of the surface. To display these on a screen, they need to be converted to meshes. If you put the display in Rhino in any shaded mode (anything else than wireframe), these meshes are automatically generated based on user-defined settings. For simple surfaces and small models, this goes very fast but it can take a while for bigger, more complicated scenes. Therefore, Rhino normally saves the meshes along with the NURBS model in the same file. This way, however, every object is actually saved twice, leading to bigger files.

The file that you attached was saved without display meshes - most likely to preserve space when sending by eMail and such. To be absolutely sure that Aspire would be able to extract meshes from the file, I just put Rhino to a shaded mode - to create the meshes in the background - and then extracted those meshes (i.e. disconnect them from their NURBS ‘parents’) by using the ExtractRenderMesh command.

Probably a result of using SaveSmall, or of using SaveAs and checking the “Save Small” and/or “Save Geometry Only” boxes.