Import STEP problem

I have two STEP file import to Rhino 6. Both model are identical in dimension except the distant from origin is different. The “Crown” model closer to the origin import correctly, but another one “Crown001” is broken. Is it the problem of the step file or import of Rhino?

Crown.step (10.7 KB)
Crown001.step (10.9 KB)

There is a micro edge in the one that does not trim correctly.
Were these files originally exported from Rhino?

These STEP files originally export from FreeCAD 0.18. However if I view the STEP file in Autodesk STEP viewer, the STEP file load correctly.

Thanks for that additional information.
This might be a tolerance thing - I notice that the STEP file uses a tolerance of 0.000001 mm and an edge on the surface of revolution that is in the front of the object is slightly overshooting the center of revolution.

At any rate, I’ve put the file on the list of the developer (RH-48029) to see if this can be tuned.

Thank you. I really appreciate your quick response.

As Wim mentioned, there are two problems with this file. One is that it has surfaces of revolution that don’t quite make sense. They are revolved circles when they should be revolved arcs. The other is that the tolerance is unrealistic.

One of the surfaces has its circle with center just slightly off of the axis, but a distance of about 0.00005, which is 50 times the tolerance, but not an unreasonable amount with a more typical tolerance.

I have put in checks for this type of problem, along with a method for correcting it. The fix will be in the first release candidate for SR9. This RC is scheduled to go out tomorrow barring any major problem. To get the release candidate, Go to Help->CheckForUpdates, and switch the Update frequency to Service Release Candidate.

Thanks for reporting this issue.

Thank you for fixing the issue so quickly.