Open polysurface will NOT create closed solid surface

Hi,
I am trying to close this polysurface however it is not working. If anyone can assist me that would be greatly appreciated.

Anna Simms 3D for review .3dm (5.8 MB)

No one can help you with a screenshot.
Please post the file.

Upated - the file is attached - it is the roof that is alone in the file that i am trying to make solid

@John_Brock are you able to help me?

Hi @Anna_Simms
it seems that your top and bottom surfaces’ outlines do not match with the edge surfaces.

a) If the top and bottom are correct, then I suggest _explode, _dupborder (for top and bottom) and _loft to create a closed polysrf.

b) If the edges are correct. Then _explode, delete the top and bottom, _join all the side srfs together and _dupborder


You need to remove this part and _closecrv in order to get 2 closed crvs.

If you _loft and _cap the top remains open, because the top edge crv is not planar. You would need to fix its planarity before you get a solid.

Thank you very much @Toni_Osterlund - how do i fix the planarity in order to get a solid?

@Anna_Simms
I would first look into the root cause, why it is NOT planar? How did you create this geometry?
Is there some steps that you could take in order to create a valid geometry from the start - instead of fixing the incorrect outcome.

After a small analysis, it seems that the deviation from plane is at maximum ~0.07mm. So completely ingronable amount.

This actually suggest that it’s a tolerance issue.
So, after setting the document tolerance to 1, I was able to finalize b) and _loft and _cap a polysurface.


There were still 2 naked edges.

The reason for it seems to lie here.


One control point is deviated from plane 0.07mm
I removed the extra control point, and got a solid!

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Thank you so much @Toni_Osterlund i finally have one closed polysurface!!

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Using an absolute tolerance of 1 is not a good idea. It is very likely to lead to other problems.rhino3d
In general you should keep the absolute tolerance setting in the range of 0.01 to 0.0001.
https://wiki.mcneel.com/rhino/faqtolerances

SetPt can be used to make surfaces and edges planar.

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