Making parallel copies

You can use the offset feature to copy selected entities and align them parallel to the original entities at a specified distance. You can make parallel, offset entities using arcs, circles, ellipses, elliptical arcs, lines, two-dimensional polylines, rays, and infinite lines.    

Making parallel, offset copies of curved entities creates larger or smaller curves, depending on which side of the original entity you place the copy. For example, placing a parallel copy of a circle outside the circle creates a larger concentric circle; positioning the copy inside the circle creates a smaller concentric circle.

To make a parallel copy by specifying the distance

   1   Do one of the following to choose Offset ():

    On the ribbon, choose Edit > Offset (in Modify).

    On the menu, choose Modify > Basic Editing > Offset.

    On the Modify toolbar, click the Offset tool.

    Type offset and then press Enter.

   2   Specify the distance by selecting two points or by entering a distance.

   3   Select the entity to copy.

   4   Specify on which side of the entity to place the parallel copy.

   5   Select another entity to copy, or press Enter to complete the command.

To make a parallel copy passing through a point

   1   Do one of the following to choose Offset ():     

    On the ribbon, choose Edit > Offset (in Modify).

    On the menu, choose Modify > Basic Editing > Offset.

    On the Modify toolbar, click the Offset tool.

    Type offset and then press Enter.

   2   In the prompt box, choose Through Point.

   3   Select the entity to copy.

   4   Specify the point for the entity to pass through.

   5   Repeat steps 3 and 4, or press Enter to complete the command.

Use additional offset options.
When first starting the Offset command, you can choose Erase to determine whether the source entity is deleted after it is offset and Layer to determine on which layer the offset entities are created.