Do I need to strip out the filler and redo my quarter panel seams?

[jtfx6552]

Back when I did this, I first plug welded with about the same amount of plug welds as spot welds.

I later went back and continuously welded the over lapped edges, I don't have pictures after that step.

I then just used regular Rage Gold over the seam. Do I need to dig the rage gold out, either fill with metal and re-do the filler, or just use a different type of filler?

Note this is a 6 CYL auto car and won't be on the track or anything.

The seams I'm talking about are at the roof and the 1/4 to transition panel. Pictures after just the plug welds, but before the continuous welds:

 

[Jim C]

i dont know what other guys are doing but i have never filled that lap with filler either butt or fully welded. i would cut that 3/4" wide lap completely out then make a filler piece and fully butt weld that like i would any other sheet metal and grind all the welds smooth like it was made as 1 piece. any time i have filled over weld without grinding it smooth, it has shown up. if its not there to begin with then it cant come back to haunt you. only way i would leave that and feel good about it is if i went back and leaded the seam. other guys may have some other advise. i am not a metalwork pro so thats just how i do it to avoid any issues

 

[Dave C.]

I’ve had good results with my process. Wire wheel the welds to remove oxidation, coat area with epoxy to seal any crevices or pin holes. Then coat seam area with short strand fiberglass filler. After blocking, use rage or any other filler to finish. My 68 Camaro was done this way 12 years ago and has 10k miles and two power tours and no ghosting or cracking.

 

['68 Coronet R/T]

i dont know what other guys are doing but i have never filled that lap with filler either butt or fully welded. i would cut that 3/4" wide lap completely out then make a filler piece and fully butt weld that like i would any other sheet metal and grind all the welds smooth like it was made as 1 piece. any time i have filled over weld without grinding it smooth, it has shown up. if its not there to begin with then it cant come back to haunt you. only way i would leave that and feel good about it is if i went back and leaded the seam. other guys may have some other advise. i am not a metalwork pro so thats just how i do it to avoid any issues

I should've done the same on my GTX.
The right side came out great with welding, epoxy, filler and paint. However the left side has one "L" shaped line showing up in the clear coat. I can sand it flat and rebuff but it keeps coming back. Is that what is considered a ghost line?

 

[jtfx6552]

I should've done the same on my GTX.
The right side came out great with welding, epoxy, filler and paint. However the left side has one "L" shaped line showing up in the clear coat. I can sand it flat and rebuff but it keeps coming back. Is that what is considered a ghost line?

Are ghost lines the main concern, or is it cracking of the filler or both?

My filler is pretty thin, and I don't see the steel flexing over that welded seam.

If it's ghost lines, wouldn't there be some risk after I weld in a bridge patch, given that my metal working and welding skills aren't near as good as some here. I'm liable to put a lot of heat into it, both welding and grinding. Further, my limited understanding of ghost lines is that they show up because the mig weld is harder than the surrounding steel, and if I do the bridge, now I'll have two mig welds albeit under thinner filler, rather than one migged seam?

 

[Jim C]

#1 ghost lines
#2 if you weld in a piece of sheet metal and the welds are grinded smooth then you should be good to go. in the end there should not be any weld tacks at all. just smooth sheet metal. it may get a little wavy from the welding and require a skim of filler to take care of that but your not burying weld tacks or have a thick filler filling in a lap joint.

 

[zachm]

i dont know what other guys are doing but i have never filled that lap with filler either butt or fully welded. i would cut that 3/4" wide lap completely out then make a filler piece and fully butt weld that like i would any other sheet metal and grind all the welds smooth like it was made as 1 piece. any time i have filled over weld without grinding it smooth, it has shown up. if its not there to begin with then it cant come back to haunt you. only way i would leave that and feel good about it is if i went back and leaded the seam. other guys may have some other advise. i am not a metalwork pro so thats just how i do it to avoid any issues

i agree with jim best way ive seen it done too cut out and make a butt welded patch basically

 

[D.A.T.]

Back when I did this, I first plug welded with about the same amount of plug welds as spot welds.

I later went back and continuously welded the over lapped edges, I don't have pictures after that step.

I then just used regular Rage Gold over the seam. Do I need to dig the rage gold out, either fill with metal and re-do the filler, or just use a different type of filler?

Note this is a 6 CYL auto car and won't be on the track or anything.

The seams I'm talking about are at the roof and the 1/4 to transition panel. Pictures after just the plug welds, but before the continuous welds:

If you have continuously welded the all the lapped edges to seal them off then you have trapped air between the faying surfaces. On the exterior of the car's surface, the roof or hood or a deck lid--full sun exposure will heat this trapped air and it is not too hard to find this ghosting when parked outside in 100F sun for a while. Lap seams are often used at weld joints on cars where these joints are shielded by other parts with some success for whatever the 15-25 year lifetime the car maker anticipated it would be actually used and regularly driven. Through the thickness of the parts, full penetration butt welds without incomplete penetration anywhere on the length, no welds full of gas porosity or the like are the long term joints for posterity.