Am I the only one? STP/IGES surface broken after importing.

[nainh]

Hi friends,

I just want to check if anyone else is encountering the same issue or am I the only one?
I do my surface modelling in NX and made sure all surface is Sew/Join properly before saving as STP/IGS file. But when I open the file in CATIA, the surfaces were broken and I wasn't able to join them without spending some time again re-modelling it in CATIA.

Is this a common issue for you too?

 

[rickyt]

I would say about 20% of the time I do not get a solid model from nx to Catia.

Most of the time I will get the model imported as a single surface/sheet/skin/volume/etc. That will not close into a solid. I then run the heal operation and that will work half the time. I have tried to reduce the nx tolerance on export of .stp, this helps some times. Last week I exported .stp and or parasolid from nx, then imported back into nx. then stepped that out and it came into catia as a solid. Othertimes we have mirrored the solid in nx then exported .stp and it came in fine, then mirrored back in catia. And sometimes we spend hours cleaning up the gaps.

 

[itsmyjob]

What is the accuracy setting of NX?

In CATIA by default it is 0.001mm. Meaning if the distance between 2 points is less than that, then catia will consider the point "at the same location" you can still read XYZ with diferent values like p1 (0,0,0.000001) and p2 (0,0,0) but you can not create la line between p1 and p2.So 2 curves are connecting when the distance is bellow accuracy... same for surfaces.

So what about your file in catia? I have heard user saying catia is not good as because the step / iges import does not show a full solid / surface. In fact the problem come from the original software that is not as accurate as catia, the geometry is "loose" but it works in the other software.

So what can you do?
[ul]
[li]Not sure if you can change the accuracy in NX to get something as good as catia. That could help.[/li]
[li]You said you are creating surfaces in NX... why not using a better software? [/li]
[li]Get some licenses in CATIA that will help with bad geometry import...[/li]
[li]Try scaling up the geometry 1000 times before export, and scale down after import?[/li]
[/ul]

Eric N.
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