Once you have a reference representation, you must manually build
a shell model to replace the solid cells that have been removed from the model.
You can use the shell feature tools and the tools in the
Geometry Edit toolset (for more information, see
Adding a shell feature and
The Geometry Edit toolset, respectively) to create and edit shell faces.
This section discusses some special conditions that may apply when you use
these tools to create faces for a midsurface model.