the front and rear screws on the passenger roof rack rails have been rusting out for years. Two summers ago I fixed both holes with some fiberglass patches, but didn't bother dropping the headliner.
Hole #1 (front screw) failed within the first few months, and hole #2 (rear screw) was bubbling again with rust. It was time to do it right and weld in patches.
Here is the damage on hole #1. Yes, I limped through winter with some HVAC tape sealing it.
I decided to cut around all of the rust and weld in square patches:
Got the patch fitted snug:
and started welding it in. This was very slow going. I think I used a whole bottle of argon to complete this.
Hole #2 was bigger and extended over the rain gutter.
I couldn't figure out how to shape the gutter so I ended up welding in two patches:
Turned up the amps for the last patch and it went much better, I think I was being too timid and trying not to blow through. I put down some bondo to smooth everything out:
For the inside, I primer/painted/cosmolined. And then cut a hole in my newly patched roof to install a solar gland:
I finished with some paint matched rattle can and 2 part epoxy clear coat spray to finish it up. I warped the roof around both patches a TON, but it isn't very noticeable unless you are looking for it/looking at the top of the roof. Turned out really good considering my skill level, hopefully this lasts longer than the last effort!
Finished putting down the siles 3-in-1 on the entire roof except where the patches were.
Up next is the roof rack, which I'm just now painting...we leave for a 6 week Baja trip in 4 days...crunch time!