To Create a Shell
1. Perform one of the following sets of steps—
a. Select one or more surfaces of the solid default body.
b. Click > 
Shell. A shell is created on the default body. An Options Toolbar opens and a linear dragger appears on the default body.
Shell. A shell is created on the default body. An Options Toolbar opens and a linear dragger appears on the default body.c. Expand the Options Toolbar to open a Floating Dashboard.
a. Click > Shell. A shell is created on the default body. An Options Toolbar opens and a linear dragger appears on the default body.
Shell. A shell is created on the default body. An Options Toolbar opens and a linear dragger appears on the default body.b. Expand the Options Toolbar to open a Floating Dashboard.
c. Click the Remove collector and select one or more surfaces of a solid default body.
2. In the Thickness panel, the default shell thickness appears. Type a value or pull the linear dragger to adjust the thickness.
3. To flip the direction of the linear dragger, in the Thickness direction panel, click 
.
.4. Click the collector in the Exclude panel and select one or more surfaces to exclude from the shell. To select multiple surfaces, hold down the CTRL key after selecting the first surface to select subsequent surfaces.
5. Middle-click to complete the operation.