IGS export fail

Hi, I’m trying to export a rather large file to IGS and keeps failing, is there a size cap on .IGS exports?
I’m getting a ‘writing of plugin failed’

Hello - can you try making a box or a plane and see if that works? Can you run SystemInfo in Rhino and post the results here?


I did a test with a sphere in the same document and it exports to IGS without any issues.
Here’s the system info

thank you !
m.system info rhino.txt (2.0 KB)

Hello - thanks - does the object report as valid if you run the Check command? It looks like it is a very complex object and iges is a text format so the resulting file is likely to be very large on disc. Are you saving to the local hard drive?


The check command says ’ Rhino polysurface object is valid.@
it is indeed a very complex object. The only reason I’m trying to export it to IGS is so that I can render it on Keyshot. When I put the Rhino file directly into Keyshot, I get some visible surface aberrations, if i use an IGS export of the same file KS shows a smooth surface.

Is there any other file extension, instead of IGS you would recomment?
I tried STEP but it crashes Keyshot…


ans -yes- working and saving on local disc, not network

Hello - my guess is that these are coming from meshing at joined surface edges- iges will be all separate surfaces and may mesh differently. You might try meshing the object in Rhino (Mesh command) and send the mesh to KS.

@mireia can you possibly export to a new Rhino file, SaveSmall, zip and post it here for us to have a look? www.rhino3d.com/upload, and include a link to this thread in your comments? thanks,


will try the meshing on rhino - thanks!-
And I’m just uploading the file to your link


Hi @mireia
You could also try the re-tesselate feature in KS. Import the Rhino file, say yes to importing the NURBS and the re-tesselate - usually numbers from 0.75 and up gives decent results.
HTH, Jakob

Edit: Just in case you have no idea, what I’m talking about: https://luxion.atlassian.net/wiki/spaces/K8M/pages/312213715/Re-

Edit again: If the geometry is really complex, you might want to increase the tessellation gradually, so that it doesn’t suddenly take hours/freeze your comper

Hello -thanks, I am downloading the file - it is very large as a Rhino file, so I can imagine as an iges file it is massive. I’ll give it a try.

@mireia - each of the two complex pieces has something over 11,000 surfaces… and these are not nearly as simple as they could be -


I was able to export half at a time… if I export everything, including the edges, I get the same error you get. If I export both complex pieces at once, it appears only one gets exported. I am still digging…

I’ve asked the developer to have a look - I do not know of a size limitation, but perhaps there is one.


Okay, thank you!
I guess I could try to export it in two halves and assemble it on keyshot - if nothing else works.

Will keep you posted in any other fix works

will try this too, thanks!

I basically have built this as a surface, then trimmed the holes and thickened it with ‘offsetSrf’ command - so these cilyindrical surfaces come from offsetSrf - happy to use any other method to give this surface a solid body

meshing in rhino (after a couple of crashes) ended up being a better solution than exporting to IGS or any other format.
Thank you all for the help.

Hello - yeah, that seems like a perfectly reasonable modeling approach, it’s just that in this case, with such a vast number of surfaces, the noticeable extra complexity generated by making those holes between trimmed edges (as distinct from trimming a simple cylinder) might add up, over 11,000 of them, to quite a bit of extra data. The other consideration may, or may not, be, that in offsetting from a curved surface, the holes are not cylindrical - they will taper, however slightly. Trimming cylinders would ensure that the holes are in fact cylindrical.


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