1. | From the Menu Bar, select Mesh Editing > Element > Modify. |
The following appears:

2. | Select the Convert Element radio button. |
Button
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Behavior
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pick parts in the graphic window, then answer the question in the Dialog menu bar with Yes or Cancel.
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add/remove the selection the parts selected in the tree.
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4. | Select Type of Conversion. |
5. | For Type of Extrusion, select Middle Extrusion or External Extrusion using the radio buttons. |
6. | Click Save to save the element modifications; or |
Click Cancel to cancel the element modifications.
7. | Click Close to close the menu. |