Best way to fix a rusted out weld seam?

[Clone TIE Pilot]

My Regal, which used to be a vinyl top is rust free except for some rust holes in the weld seam between the rear quarter panels and the roof. Here is a picture showing the area the rust holes are in, (the pic is not of my car).

Welds tend to rust faster than the base metal. The rust holes are only in the weld/braze mix itself caused by the crappy body filler GM used that had popped out. I am thinking about brazing the hole since GM has already brazed around that area on these cars. It is not a good spot to just cut out and weld in a patch which is often done these days. Stupid vinyl roofs. At least the vinyl kept rain out so the rust is localized to the welds.

 

[jdietschweiler]

Bump 🙂

 

[Blew86442]

Make sure you get ALL the rust out. You can re-lead. Try to patch in some sheet metal. And you can always use filler, with the longer strands of fiber glass. I would just do the filler with fiber glass. It is some STRONG stuff.

 

[L92 OLDS]

Where do you live? I know a very talented body man that specializes in lead work in the Lansing MI area.

 

[Clone TIE Pilot]

I am in NJ, the vinyl roof cars just had seam sealer put there instead of lead like hard tops. The holes are in the seam itself so cutting out and putting a patch panel in is not good for a seam. Also the seam has been brazed by the factory, most quarter/roof seams on cars made of mild steel are brazed. Which is why I am thinking of brazing the holes shut, just as strong as welding but not nearly as much heat to burn though or warp the thin panels. Brazing is sort of like soldering but with bronze instead of lead, it isn't used on modern cars made of HS Steel since torchs crack that type of steel.

 

[dixon_ronald]

Try and get some pics on what you get done for the repairs. I have the same problem on my Monte. I pulled the crappy vinyl and found rust near the same places as in the picture AND i have rust along the opera window. Should the opera area be done the same (brazing), or done differently?


I was actually thinking of finding a donor car to cut out the metal for the opera window areas and possibly across the top of the car where the vinyl top attached.

 

[Longroof79]

I wouldn't recommend brazing. Whatever you apply over the brazed area will not adhere properly over time. That could account for them using lead over any brazed joints. I suppose using a good two part epoxy or All Metal might work.
Perhaps you could put a patch in, and have it TIG welded.
Just a few thoughts.

 

[james@pst]

What I normally do is clean out as much rust as can as it looks like you did. Then I use a acid based metal solution. Dupont use to make one I believe the number was 5717S, but por15 carry something similar called marine clean. This will stop any rust that is still there. Then neutralize it and then I normally lead the seam or you can use 3m's epoxy based body panel adhesive as filler its like a rock . Just my 2 cents

 

[Clone TIE Pilot]

I was thinking of using autobody structural adhesive (stronger than panel adhesive) to glue a metal patch there. GM just put seam sealer right over the brazed spots. Things can stick too brazing if you clean the flux off well and tin them, but adhesive may be better. This is a high flex spot so I think metal fill type bondo is a bad choice since it is more brittle.

 

[james@pst]

The 3m panel adhesive is pretty strong. Now a days they use it glue on roof skins and 1/4 panels on new cars. The metal will rip before the glue lets go strong stuff. We use to use it all the time in the body shop that I worked in.