Hi, yes you are right, the two pieces are not joined together. I tried boolean/union, but that didn'nt looked OK. Now I tried Edit/Join as you suggested, but it still looks strange.



"Also if your object is not totally smooth where 2 open surfaces touch one another it can be difficult for Shell to thicken it properly especially in the area of the sharp corner. This can work better if you shell with a solid base object instead of with surfaces."

I did try to mirror my lines before the loft, but it wouldn't close properly, there was a twist in the last part. So first I just lofted that last part.




Then I tried to "reloft" a few lines, which looked OK, but then the shell went nuts.








Attaching the 3dm-file.

/Lars