There has been a lot of talk about body cracking around the curve at the deck lid. How do you fix the cracks. I removed the lead that was cracked expecting to find a crack in the sheet metal. The metal loks sound with no cracks. Is it best to re-install the lead or should body filler be used? I am installing a rigidity kit to help stop the cracking in the future. any help would be appreciated.
Richard T.
Original Post
The consensus was to use body filler. The problem with the lead was its expansion and contraction rates were so different than the steel that it was causing the cracking. Modern body fillers are much better than they used to be and should solve the problem. The stiffeners that DOES 200 referred are extra insurance.
Richard .... one question that has always remained in my mind was why the American Cars dont crack in this location due to the "LEAD" ... could it be they used "SOLDER" and not lead ?

Personally I would weld in the steel and body filler it over ... who wants a crack after a nice paint job has been applied /

Ron
I'm not the expert on this type of a repair BUT I have found that using brass, I.e., brazing it will help a lot. It is softer then a steel weld BUT has flexibility to it and is much stronger then the lead which I think in this case is just work hardening and cracking, not the sheet steel.

Brazing has been used forever on steel bodies and I think that this may be the reason? Wink
Richard,

If you are about to repaint your car you have the chance to stop the cracks permanently. As for the deck lid opening curve cracks, like the other guys have suggested, I think you should weld these areas up with reinforcement plates welded in from behind. Cut the plate out of 1.5 or 2mm thick steel and drill lots of holes in it so you can plug weld it with the MIG. The idea is to spread the stresses over a wider area. The plate you weld in will be a boomerang shape and be approx 200mm (8") wide. The most important thing of all is after you have welded it in to clean up area and seal the edges with a body caulking then paint it really well. If moister gets between the plate and the sheet metal it will rust and after a few years bulge the two pieces apart causing ripples in you body work. If you seal it properly you will never have a problem.


When I rebuilt my car I did not weld a plate in this area (even though Jack DeRyke told me to) and now wish I had. I lead loaded it instead. It took about 10,000 miles for the cracks to return. If I had driven it on a track I think they would have reappeared a lot sooner.

At the base of the windscreen pillars I did some reinforcement with the MIG from the outside and then lead loaded it. I have not had any cracks yet after 19,000 miles.(but I still have not driven the car on a track) I basically removed all the lead and replaced it with MIG weld. I think what Julian suggests is the best thing for this area, weld in a T piece that goes up the A pillar and then attaches to the bulk head unde the fender. This is very complicated though and I have not tried it yet.

The other crack you need to address are around the tail lights where the rear panel joins the fender. I lead loaded mine and the cracks returned very quickly. Next time I paint the car I am going to reinforce the area by welding in a steel reinforcement plate. Kirk Evans told me he adds a thin tubular support rod that attaches to the lower corner of the rear fender near the exhaust can (the flexible bit) and braces it to the chassis above to stop with flexing up and down. He says he has not seen the tail light cracks return on cars that he has done this to.

Another thing I think you should do is make a plate to go around the door handle on the inside to strengthen the area. I have seen lots of cars with beautiful body work spoiled by a dent around the door handle. It is never the owner of the car that does this but other people that dont know "you MUST NOT close a Pantera door by pushing on the fu**ing handle" I think they should teach this in schools.
I think the best thing to do here is to bond the plate in place with one of those super strong modern automotive trim adhesives. This would have to bond to the bare metal though. You can also attach the U shaped sheet metal part the door handle bolts into to the frame that runs above it. I did this with little bracing rods.

I lead loaded all the key areas on my car and 10 years later have not had any bubbling or problems other that the cracks caused by the body flexing (not the fault of the lead). I dont think I would ever used lead again though, I think it's unnecessary these days. Plastic fillers are better than they used to be and any areas that are likely to flex should be welded up properly. As a filler, lead, when done properly is still way better than any plastic filler but is not the answer to the Panteras cracking problems. It's also a pain in the ass to use. Apply some lead to a flat piece of sheet metal and then see how far you can bend it before it cracks, you can nearly fold it in half! Plastic filler cracks after about 10 degrees of flex. Lead is heavy, so next time I paint my car it will be gone!

Johnny
Good synopsis of the problem, Johnny! On the front windshield piller, Dennis Quella uses (and sells) a 'chicken-foot' shaped piece of steel welded/brazed to the fender at the junction where the fender & piller come together. But I've seen nothing for the top joint, and have noticed cracks on Panteras there too. Unfortunately, it's usually the racers that seam-weld the entire body/chassis for vastly increased stiffness and handling improvements, but such work would certainly benefit all Panteras. I keep thinking of Carroll Smith's analysis of the Pantera's monococque for Ford management back in 1971: "....The Pantera is hopeless as a (potential) race car. .... the rear suspension is attached to nothing at all...." And years of pot-holed street driving do not improve the situation. Mangustas and Vallelungas are even worse for cracking (frame members not body panels), both being essentially lightweight formula-car chassis with a heavy 2-seat body grafted on. I suggest closely checking your DeTomaso for cracks yearly, and note where the trouble spots are on your example so someday (maybe tomorrow?) you can have them professionally corrected.
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