Is there a special function?
Duh.. Found it under another discussion right after I posted. Sorry.
If you are using "Mass Properties" on the image above you are only getting the volume of the sheet metal. If you want to know the total volume of the inside cavity, as if it was full to the top with water, then you will want to fill the inside with a solid feature and use that new body for your volume calculation.
This can be done by -> creating a surface on the top edge -> converting the inside edges -> extruding with direction up to body and merge results unchecked -> Now select this new body for your mass property.
thanks. I noticed this so I rolled back the shell feature and measured the volume before shelling.
Retrieving data ...