With Creo 7.0, in addition to center lines, you can select any straight sketch entity to define the reference to mirror about. Other entities for the mirror reference include the horizontal and vertical sketch reference lines, and other straight geometric entities, such as model edges, projected geometry, curves, standard and construction sketched lines and center lines.
By default, the geometric entity that is used as the symmetry axis for the mirror is not locked.
Tips: The symmetric constraint also supports using any straight entity as a reference.
User Interface Location: Click Model > Sketch, select the sketched entities you want to mirror and click Mirror.
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