export Weldment Centerlines only or mirror a 3D sketch?

Is there any way to mirror parts of a 3D sketch about a plane?  I've  built a weldment spaceframe and I need to export all the tube  centerlines as a 3D sketch in *.igs format for our CNC tube  bender/profiler.  The problem is that I created the part by only making  1/2 of it as a 3D sketch and then mirroring the weldment BODIES over, but now I  need a full 3D SKETCH of all the centerlines.  I either need to mirror  my original 1/2 3D sketch over or export only the tube centerlines somehow?  They're all circular tube profiles so hopefully that helps.  Thanks in advance!

SolidworksImport export