Face Extrude Modifier

The Face Extrude modifier extrudes faces along their normals, creating new faces along the sides of the extrusion that connect the extruded faces to their object. As with most modifiers, this affects the current face selection passed up the stack. There are various differences between the Face Extrude modifier and the Face Extrude function in an editable mesh, especially the fact that all parameters in the Face Extrude modifier are animatable.

Faces extruded on the top and along the edge of the object

Interface

Modifier Stack

Extrude Center

At this sub-object level, you can select and move (or animate) the center point. This affects the geometry only if you turn on Extrude From Center.

For more information on the stack display, see Modifier Stack.

Parameters rollout

Amount

Determines the extent of the extrusion. You can adjust and readjust the Amount spinner as often as you choose. To extrude a second level, apply another Face Extrude modifier.

Scale

Scales each cluster of selected faces independently about its center.

Note: By using multiple extrude modifiers with Scale, you can achieve a bevel effect.
Extrude From Center

Extrudes each vertex radially from the center point.

The direction in which the faces are extruded is slightly different than Face Extrude in the editable mesh. Each vertex is displaced in the direction of the average surface normal of selected faces that share that vertex. So each vertex may move in a slightly different direction. Put another way, each vertex is extruded in the direction of the surface normal at the point on the surface where that vertex lies.