Extrude

You can use the Extrude option to extend a polyline or surface geometry entity along an arbitrary axis to add a depth dimension to the shape. Essentially, you are copying a geometry entity along a defined axis to generate a new 3-dimensional entity. An extruded line would generate a surface. An extruded surface would generate a volume. You cannot use the Extrude option on a volume. To use the Extrude option:

1. Select the Geometry workflow tab.
2. Select any number of polyline or surface geometry entities.
3. Select the Extrude option from the toolbar or the Extrude/Sweep/Loft Tools sub-menu in the Geometry menu.
4. A dialog should appear. You can use the Add Curve and Delete Selected Curves options to add or remove geometries to the list that will be extruded. You can also use the drop-down menu beside each item to change the geometry selected.
5. If you enable the Close Volume(s) checkbox, the program will attempt to convert a closed polyline to a polygon before extruding it to create a solid volume. This is useful if you want to draw the cross-section using a polyline and then extrude that section to create a solid volume.
6. Define the extrusion Direction by entering the XYZ vector components or by selecting the x, y, or z-axis. You can use the Flip option to reverse the extrusion direction.
7. Define the extrusion Size to determine the total Depth or distance you want to extrude your geometries as well as the Offset which is the starting position of the extrusion relative to the original entity position, measured along the extrusion axis.
8. You can use the Preview option to view your extruded entities before you accept the changes by pressing OK.