Boundary surface returning error


Hello everyone, I am trying to create a boundary surface using the highlighted curves but I keep getting the error shown and it does not create a surface. I joined the curves using the join curve feature but it is still not outputting a surface. Any help would be appreciated!

Post your file

Kresling 30,38 FINALVERSION.3dm (104.3 KB)
Kresling 30,38 FINALVERSION.gh (51.3 KB)

Sorry, if my file is a bit disorganized

The right side of your object is not planar.

Flatten the input of the Join Curves component and one side is done…

I’m not going to dig through your definition but the other side has to be planar if you want to cap it.


Ok, I just tried that and it worked for one side but it is not working for the other side for some reason. What is causing this?

What’s the actual goal of your definition?

I have a feeling you’re after something like this (check file attached)?

twisted_polygon_brep.gh (17.2 KB)

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Yes that is what I am looking for. Wow your definition is so much simpler! I am really new to grasshopper so I am still not familiar with the best ways to construct things.

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Please click the solution box above if you’re happy with my definition. Thanks :slight_smile: