After a frustrating afternoon trying to make Curviloft skins some surfaces, I started to suspect that something was wrong with my contour not with Curviloft. So I split the surface and try to manually close it. I found that on 5 areas triangles don’t close the surface. I can’t find anything wrong on the surface border it is simple and seems perfectly normal, correctly connected and aligned. I attaches the file. In Green what I was able to automatically skinned with Curviloft. In Red the areas that don’t want to close, event manually, (and preventing Curviloft to work). In Yellow a triangle that close but with apparently a distorted geometry. Any idea?curviloft.skp (246.9 KB)
Thanks!
You have some inaccuracies in your model.

I’ve corrected the geometry and you can see it now works.

Thank you Box. Pretty obvious, I was expecting something like this but missed it for some reason. I was working on my laptop, not the best video card. I also fix it myself as a learning exercise. I don’t know how these inaccuracies happened. This issue is really what bothering the most in Sketchup, happening often without clear reason.