Create cross section planes:
Use the default XY cross section plane.
Select a plane from the Cross Section tab.
Select a face in the graphics area, then select Face Plane on the Cross Section tab.
Double-click a point on a face to create a cross section plane parallel to the face.
You can drag the plane to change the cross section.
To create and manipulate a cross section:
Click Cross Section or Tools, Cross Section.
A cross section plane appears, normal to the model.
Drag the plane, which moves along the axis normal to the model.
On the Cross Section tab , select from the following options.
Face Plane. First select a face, then select this option to create a plane parallel to the selected face. Double-clicking a face also enables this option.
Flip. Flips the model along the currently displayed plane to display the other side of the model.
View normal to Plane. Displays the model normal to the plane.
Show Plane. Shows the cross section plane.
Show Cap. Displays the edges as capped solid faces.
Cross section capped and solid
Cross section uncapped and hollow
To release the Cross Section tool, click it again.