Fusion is struggling with complex body, shell and offset error

[Ceecis]

Trying to shell by selecting this face fails.

Trying to offset this face also fails.

[henleyi · Accepted solution]

Hi, Fusion is struggling to offset this face because there are some very high curvature regions on the loft surface. These will fold over making it difficult to produce a legal offset surface. The highest curvature is concentrated in this region:

Removing the problem part of the surface can help, for example one solution could be to cut out the problem area and fill it with a surface patch. 

This allows shell to work up to about 0.2 After that it fails again due to more high curvature.