Three cracks appeared while the car was in winter storage. it was fine when it went in and happened sometime over the 5 months it was in covered storage. The tail lights are frenched but are all steel welded to the body. No bonded pot metal was used. What really throws the WTF factor at this is that the cracks appear in the same location on each side of the car, which, to me, would indicate some kind of an assembly, welding, problem. I've had certified fabricators and bogymen look at it but no one has a logical answer. I don't mind fixing it but would really like to be sure I addressed the issue that caused the problem in the first place. Any experts with an opinion, out there?
Was the car on jack stands while stored?
it seems to be on the concave part of the fin to trunk area. I have had such a crack happening once, when 1/16" thick plastic was used to radius a concave area. possibly the primer/filler wasn't sanded thoroughly. Paint shrinks in low temps and will pull off to the point where it cracks.
Doug...........have you asked your bodyman about his thoughts? I remember seeing the pics of the welded assemblies when you were doing it.
A non-expert's thoughts: You probably won't know for sure until you dig into it. It would be my guess a fair amount of body filler was used in those areas to get the contour perfect. In my book, that's not an issue as long as it is applied properly.......the key factor there is having a very coarse surface to apply the filler to. If applied heavily to a smooth (as in sheet metal stock surface), you could have adhesion problems. However, I don't think that's the case here. An adhesion problem would show up as a lifting, not a cracking. The more likely culprit without knowing exactly what your body man did..........I found that 2k primers built up heavily for smoothing/blocksanding can be an issue in the corners/concave surfaces because the primer shrinks over time. Not necessarily an issue on large flat surfaces, but in corners or other niches where it can build up more, it can be a problem when that excessive buildup shrinks over time. Just my guess.
Keep us posted as to what you find, and come back once in a while even if it's just to say Hi. in our morning coffee section!
Looks like a possible Fiberglas crack. If there was any of that done in the process of the work, (and knowing how cold it got this winter in your area) might have caused a serious shrinking of the material causing the crack.
Like Rich said though...until it gets dug into...not going to know for sure.
Looks like filler shrinkage given the cracks run along the transition from the tail bezel to the trunk area. Too thick an application in one shot. To fill an area that requires a bit of build up multiple thin layers with a couple of days between application will prevent the issue you see here. (IMHO)
Thanks for the feedback. you guys are pretty much in agreement with the people I have talked to locally. My concern is the thickness of the filler that was used. The bondo work was done by a fairly high end, local, street rod shop and I would think it was done correctly. We will, hopefully, dig into it in the next few weeks to see if anything obvious shows up.
I might be coming through that way on my return to Port Angeles. I will let you know if I am. Have a buddy there, Bob Kiddy, who just finished his new shop to go with his new house in Richland. Told him I was going to store a bunch of my stuff in his new shop while I move from WA to MO. LOL!!! don't think that will happen. He almost has it full already. Hehehe!
My money is still on maybe too-thick layers of 2k primer. We've all seen the ridiculously thick layers of bondo on cars that we had no idea of, until stripping started..........it just doesn't seem to shrink and crack.
yes Rich, and poor adhesion between layers because of unsufficient sanding or smooth metal surface.
Something like that would really make a person sick, especially after the car got painted.
Problem solved! Looks like one of the people who helped with the tail lights overground a couple welds and they cracked. The third crack looks like poor adhesion and some surface rust. The two cracks have been cleaned up for repair, they weren't this wide open.
Thanks for keeping us updated. I'd be more than a little angry. Is the guy who did the original work doing the repair?
one of the hardest skills to learn is when to stop
yes but what about the surface rust on the low spots next to the welding ?
there could be more to the problem than just the metal cracks. still annoying to say the least.
All the issues are being addressed.. re welded and some spot blasting to fix the bit of surface rust. Three different people worked on that project so I really don't know who did the grinding. as far as the surface rust goes, we know some water got in thru the cracks and I suspect thats how that happened. I am confident that the guys who did the bond work did not apply to rust It's easier to just get it fixed and get ready for another summer of enjoying the car.
well said ! enjoy !
Quote from: 57imposter on 2020-02-18 18:37
It's easier to just get it fixed and get ready for another summer of enjoying the car.