Basically I created this surface as one half and mirrored it, I have knitted the surfaces but when I try to thicken the surface it give an error.
Attached is the file
A solution will be much appreciated
Is that really how you want your body to terminate at the top most portion of the part? If you cut that portion away using a surface trim the rest thickens just fine. You will have MUCH better luck doing that top termination as a separate face (with another surface trim or a surface fill, optimize surface disabled) prior to the mirror. Just about any loft that goes to a point like you have is going to have issues with thickening (or shelling, which is kinda-sorta the same thing)
Thanks for the reply
I managed to sort it out there was just an area of the loft which didn't meet at a tangent so this is fixed now. I will bear in mind your advice.
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