The computer freezes when you choose the shell command and enter the thickness

[mkaplan4ZME2]

Hi, 

While I was designing bike handlebar grip today, I needed to choose shell command. But when I choose it and enter the thickness, the  program got frozen and it gave an error. I then tried several times, entering diffrent thicknesses but it always got frozen and threw me out from the program. Why does this happen?

[HughesTooling]

You will probably be better off just extruding a circle through the part rather than shelling. That's quite a complicated shape to offset and only likely to work with very small offsets, less than the size of the smallest feature. Don't know how big the part is but try something like 0.1mm and see if it works. CAD programs like Fusion do not like offsets that will create self intersections.