Paint cracking over seam sealer

B

bluebronco70

I have an early bronco that I just painted SPI red single stage. I seam sealed the rear rocker panel joint before painting and now it has cracked when I lifted the body off of the frame. I kind of think I I should have never seam sealed the joint. Have any of you dealt with something like this and fixed the issue by touching the area up? Would you leave the seam sealer or dig it back out (which would suck)? I'm just afraid that I might have to take out the sealer and repaint both quarters with a new gallon that I'm not totally sure would match, so I wanted to see if there is a way out there to fix my issue. T
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hanks.
 
Well, the joint is obviously more flexible than the sealer can handle. It will probably get worse, but if you don't want to repaint it, touching up is the only option. I'm guessing very few if any will notice. Kind of a shame, sorry about that. What kind of sealer was it, so we know not to use it?
 
The great part about single stage is how well it can be filled, sanded, polished and then repeat if needed. If you spend enough time on that just with a little dabber, and building it up, sand it, feather it in, could be almost unnoticeable. I personally would not take the chance on matching issues for that, I would spend the few days it will take you to do a really good touch up.
 
Yeah, the SS will wick into the crack, needs a number of applications until it is filled up, and it will end up looking fine. Problem is, it will be susceptible to cracking more in the future.
 
I'm probably wrong, but isn't is a pay me now or pay me later sort of thing? If it cracked that easily moving the body, won't the body flexing as the car is driven cause it to continue to crack?

Just my opinion, but if it were my car, I would grit my teeth, grind out the seam filler, and repaint the area.
 
I think if a guy was super careful, and a little lucky, the seam sealer could be carefully removed and replaced, and then touched up with minimal appearance problems, mostly because it is a solid SS. But that wouldn't work if it's expected to be "perfect."
 
It was SEM 2 part seam sealer. I don't think it is the sealer's fault and I'm not totally sure the sealer has cracked. To me it looks like the paint was just too thick to handle the flexing. Also, when I hoisted the body up, it was braced but it still bent. After the damage had been done I repositioned my mounting points and the crack in the paint got visible smaller, but I would say it is a high flex area, so it might want to crack again as I drive it. It won't be perfect by no means as I want to drive it as much as the weather allows me to too, but the crack looks a little "flaky" and I don't want it to spread. So saying that, is it a good idea to remove the sealer and try to touch it up, and if it doesn't work go ahead and repaint it? How exactly would you guys go about touching up the seam?
 
I would:
Mask off on both sides of the seam; first paint masking tape, then several layers of duct tape or packing tape.
Since I'm a woodworker, I would make up a fixture out of plywood with a slot that I could center over the seam and figure out a way to make blocking so I could clamp it in place.
Score through the seam a couple of times with a sharp knife.
Use a Multimaster or similar vibrating cutter with a fine saw blade to cut through the filler, then use the same tool and blade to cut away as much filler as possible without scoring the steel.
All of this is done through the slotted plywood-that way, it would be nearly impossible (nearly but not completely!) to slip out of the seam and damage the paint.
Once it was cut through and as much as possible was removed, I would remove the fixture, keep the heavy masking at both sides, then clean up the balance with files and sandpaper.
If I decided to seam seal it again, I would prime it then seal, keeping the sealer much deeper into the seam (no where near the face of the seam).
Unmask, feather the edges, remask, prime, and touchup spray.
With any luck at all, you will be able to cut and polish the touchup into the existing SS without respraying the entire panel.

Anyway, I am new at this game, so I may be all wet here. It won't hurt my feelings at all if the more experienced guys disagree with me.
 
I might carefully V out the crack with a razor blade, mask it off, tool in some real rubbery stuff like windshield urethane, then smooth it with a few drops of xylene or slow reducer. After it cures overnight, brush touch it.
 
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