Weld seams showing through new paint job

[gearbanger]

That happened on mine. I dont think it has to do with aftermarket sheet metal, or the lap welded joint reacting to heat from sunlight differently. Mine shows up in the garage or in the sun the same. Mine did occur a few weeks after being painted though, the same as everyone elses. I have PPG acrylic enamel on mine, no clear.

My body guy overlapped the panels and welded them solid, ground the welds down, then went over them with a short hair fiberglass filler. Then he skimmed it with plastic filler and primed and blocked until it was straight and slick. It looked great for a while but you eventually could see every inch of the welded seams. I really think it is more of a shrinkage of the fillers over time.

Butted or lapped, I think if the filler has any thickness at all, its going to shrink and show. It might evern be a reaction of the solvents in the paint with the fillers that it is being spryed over. I dont know if some kind of sealer before paint would have helped or not. Maybe?