How to mirror model lines in a 3D object?

[Mehdi.Kardehi]

I want to mirror the model lines I have drawn on one face of this machine to the other size...but when I select them and I change my view to pick mirror axis I can't do it as the selection get missed... Any help?

Model lines are inside that red thing I have attached

[ajax05k · Accepted solution]

After selection of lines you can save the selection set, so that in future when you want that selection set you can have it. For this select all the lines-> click on save-> [which is beside the filter ribbon] give some name to it, thats it now you can load the selection set whenever you want