Closing twisted tower


I have created a twisted tower in grasshopper but I am struggling to define the zagged surfaces pictured below:

(I actually managed to do it in an other model, but I had some other issues with it so I decided to restructure it. Unfortunatelly now I can’t figure out how to do it properly with the new model.)

In my first solution I used the boundary edges to form a zagged surface (see picture below), but now the data is differently structured.

The .gh file: (33.5 KB)

I labeled the groups for betted understanding as it is a bit complicated. And also here is a picture about the main steps:

What would you recommend for defining the closing surfaces?

Not sure BTW, Is this what you are after? (44.8 KB)

Yes, exactly, thank you for your help!