Right Rear Wheel Opening Repair

As the weather continues to deteriorate here in Michigan, and I am desperate to avoid listening to political bull$h*t through every conceivable communication medium on the planet, I have had plenty of motivation to keep myself occupied in the shop as much as I can.

The latest bit of progress was to fix the front corner of the passenger side rear wheel opening where I discovered a small patch of rust that I had not seen before.  This spot was a bit of a heartbreaker as the outside skin only showed a very tiny pinhole of rust, whereas the back side was rusted through and hidden by a generous dollop of seam sealer that worked to trap moisture in this one area over the decades.  Once I got the sealer removed, this discovery let a bit of the air out of my sails knowing I’d have to cut deeper into the old girl than I had hoped.  But…….she deserves the rehab, so off I went!

The first order of business was to mark the general area that I would need to remove so I could fabricate the necessary patch and then use the finished patch itself as the pattern to make my final cuts.  I first cut out the damaged area well inside my marks to leave plenty of material to work with when the final fitting of the patch was at hand.  After the outer skin was removed, the full extent of the damage could be easily seen and assessed.  Then I made a pattern and fabricated the rather simple patch and then traced it on the parent metal to allow me to very precisely fit the rough opening to the new patch.

Once the patch was ready to go, I then carefully removed the damaged inner structure and then cut out the necessary patch from a leftover outer wheel house patch panel I had on hand.  This was a rather simple proposition that allowed the inner patch to be welded into place quite cleanly and the welds dressed down before the outer patch was to go into place for the last time.  I should mention that I tried to keep the gaps quite tight between the patches and parent metal to ensure good penetration without blowing holes through the whole works.

I finished the job by carefully clamping the outer patch into place and tacking it into place at several points around the patch to ensure good retention and to allow many heat paths to soak up the weld heat and dissipate it more easily without warping the panel.  Then I slowly and carefully stitched the patch into place and ground all of the welds down smooth.  The end result is a nice clean patch that will require only a thin skim of filler to become completely invisible.

Next stop will be to repair similar damage on the driver side rear wheel opening.  Because this will involve repair of the rocker panel as well, the complexities of the repair will be considerable in comparison to this one.  But I think I might have it covered!

The white paint lines show the max extent I intended to remove and the patch I began fabricating.

I start cutting out the repair area well within the paint lines to allow me to use the patch as a precise trim pattern.  As you can see, the damage behind the skin was rather severe, but fortunately pretty localized.

Here is the new patch fit and the parent metal trimmed to keep the gaps tight for good weld penetration without blowing through.  Once the fit was exactly as I wanted, I marked the patch for position and set it aside.

With the outer patch fitted, I could concentrate on fixing the more damaged inner wheel house section.  With careful measuring and some work with the air saw and cutoff wheel, the offending area was cut away and a patch was fitted and welded in place.

Finally, the fitted outer patch panel was welded into place and metal finished.  A very light skim of filler will have this area completely undetectable in finished form.