I'm trying to put a 16mm hole through the centre of some 35x35x2.0mm square hollow section (SHS) gal steel. The holes need to be fairly accurate, because they're going to be holding an axle that needs to be straight. I put some 3mm pilot holes through both layers with a drill press, but the press table flexed, and now my holes on the back side are out by about 1-2mm. That's really gonna screw up the axle.
I can't easily re-drill the holes, because the correct centre is inside the existing pilot hole. Is there a simple way to fix this mistake, and get a hole centered in the correct position?