Deformation when using flow along surface

Hello @pascal , I am sorry to disturb , but I am again in a similar problem so I thought I could write in this post.

I have a polysurface that I created by using the “sweep 2 rails” command, and now I can’t use the last solution (UnrollsSrfUV) to have my curves on this polysurface. I tried to project curves, to create a surface instead of a polysurface but nothing wokred so far. Is it possible to somehow project flat curves onto a polysurface without deformation?

Also I looke dinto similar issues but it does not answer my question (Problems projecting closed curve mesh onto curved polysurface - #2 by anon55473861, Can't project a group of curves onto a polysurface. Any idea? - #5 by davidcockey) but I still cant make this polysurface to be a surface.

Any help would be very useful :slight_smile: