Creates a special object called a shell from a group of surfaces, in preparation for Boolean operations or export to a CAD package.
This slider only appears when is turned off. If the gap between two edges is within this tolerance, the edges are joined. The range is 0.0001 to 1.0000
Detach the seam of periodic surfaces (that is, closed surfaces such as cylinders and surfaces created with the tool) before stitching them into a shell.
This option is sometimes necessary when the stitch function does not notice that a surface edge is attached to another edge on the same surface. This is a common problem in CAD systems.
Detach trim edges made from single curves on surface (such as a round hole in the middle of a plane).
Some CAD systems have problems with these kinds of trims. Turn this option on to allow export to those systems.
Keep the original surfaces after the shell is created.
Depending on how you set the options, a shell may not match the original surfaces exactly. In this case, unstitching does not produce surfaces that match the originals exactly either; it is a good idea to keep originals. The default is to keep the original surfaces.