Creating solids and surfaces by extrusion

Often we create a 3D model from 2D drawings by extruding (giving height) to planar entities or closed areas. For instance, in architecture, we may construct walls from plan views. The following sections present the commands for extrusion.

Extruding 2D objects

Probably the most used command for modeling in 3D is EXTRUDE, which is presented next.

The EXTRUDE command

The EXTRUDE command (alias EXT) allows for extruding or giving height to planar entities, thus creating volumes. The command starts by showing information about the wire frame density and the MOde default option; it then asks for the objects to be extruded:

Command: EXTRUDE
Current wire frame density:  ISOLINES=4, Closed profiles creation mode = Solid
Select objects to extrude or [MOde]: Selection

By default, the command prompts the height of extrusion:

Specify height of extrusion or [Direction/Path/Taper angle/Expression]: Value

All the selected objects are extruded. If the original object is...