The Convert to 3D Polys command converts any 2D line or surface object, including polylines, polygons, circles, ovals, and rectangles, into a 3D polygon. Once converted, the new polygon contains a Z dimension, assigning it a place in 3D space. It can be rotated and manipulated with 3D tools. The new polygon will not, however, have a thickness.
When you convert two or more objects simultaneously, the converted objects are placed in a group.
To convert a 2D object to 3D polygons:
Select the 2D object or objects to convert.
Select Modify > Convert > Convert to 3D Polys.
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