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  #21  
Old 05-18-2023, 07:49 AM
schwemf schwemf is offline
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I've drilled out all the spot welds but that has proved to be insufficient for separating the hood skin from the hood brace. There's not enough flex to allow the two pieces to be separated as the skin is still held in place on both ends. Perhaps cutting the flange at the front would allow more wiggle room, but I'm not holding my breath, but will try on the scrap hood.

I'm having to think about your suggestion, to cut slits in the high area. Is the process:
  • cut an "I" slit along the highest stretched contour
  • lower the high to level or slightly high
  • remove any overlapped metal
  • If that's insufficient, cut the "I" slit into a "T" slit
  • repeat
  • If that's insufficient, cut the "T" into an "H"
  • repeat
  • I'll be done when the contour is even or slightly high
  • weld
  • shrink to the proper contour or slightly low
  • fill


Continuing on perhaps my ill-fated process, I have removed the "caulking" that the factory applied between skin and brace. That has allowed me to pick up the lows from below as well as slide a thin spoon between hood and brace to on-dolly level. But of course that just means more stretching, and I understand your concern about shrinking such a large area.
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  #22  
Old 05-18-2023, 11:25 AM
John Buchtenkirch John Buchtenkirch is offline
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Just carefully fold up that rear hem. Just a few degrees at a time, then a little more and so on, DON’T try to fold up just one area all the way. It may help to heat the very edge with a torch to soften it. Remove paint first so it heats instantly then QUICKLY unfold. If you heat it to red you may have to deal with some shrinkage so I’d try without heating it first. You may have to make your own tool (an old heated & bent screwdriver will do) to start raising the edge.

You have a little bit of a tricky job there but it’s not nearly as bad as removing a door skin where you have to unlock / unfold 3 or 4 sides. I can cut off a quarter panel (that I’m not saving) in a half hour but removing a door skin that I’m saving can take 2 to 4 hours, maybe even more . ~ John Buchtenkirch
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  #23  
Old 05-19-2023, 03:32 PM
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drivejunk drivejunk is offline
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Fear not. I did a 59 Catalina trunk lid and will tell you how. You interpreted the ITH concept as intended. Practice would give you an idea of how high to leave the trimmed overlap area, to compensate for the anticipated shrinkage from welding. In order to minimize the need for planishing.

Spotweld cutters may not apply to what I am about to show you, and I have indicated grinding in this sketch because foldover spotwelds are small but tenacious and foldover edge damage, while inevitable, can be kept to small bites. Which are where you'll re-weld anyway when done. All foldovers have welds along them. They are few but critical for panel rigidity.

Getting to the point...

On the 59 I went in with the unfold with heat mentality as well. And I do have a suggestion for a tool for unfolding if you persist with that method. But theres another way and it worked for me cold and easy, made me look like a champ once the thought occurred. I had a ring of weatherstrip rust thru all around which made the decision easy. Messing with the foldover wasn't winning.

So see the attached sketches. This was the way I found to skin the cat, pun intended-





Thats my input on how to lift the shell out of the inverted skin. Lop off the captive edge and replace it. Probably rotted anyway. I hope this serves as helpful thought fodder while you choose a path. Nobody would ever see an overlap with plug welds out near the edge.

My Pontiac (longest hood on a production car) stops the foldover a few inches from hood rear corners and has a vertical spotweld flange there. On mine or yours... yes preservation of metal thickness is job#1. You have your work cut out for you. Continue telling us how you do.
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File Type: jpg Resizer_16845259665301.jpg (63.6 KB, 244 views)
File Type: jpg Resizer_16845259669323.jpg (57.3 KB, 242 views)
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  #24  
Old 06-14-2023, 03:42 PM
schwemf schwemf is offline
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Testing this process out on my spare hood, I've separated the hood skin from the brace, so now I have access to both sides of the hood skin.

IMG_20230604_132656839.jpg

IMG_20230613_173343157.jpg

I followed the process detailed by Matt. The critical decision was where to make the cut in the brace.

I chose a location where, if I decide to weld, the brace and skin are furthest apart (about an inch of air space between them), so the heat from the weld would be kept as far from the skin as possible.

Plus, this area of the brace is strong, bordered by two adjacent 90 degree bends that should resist and limit any heat distortion of the brace itself when welding it back together.

Finally, the back side of the weld, that I won't be able to finish, will be hidden from view.

In summary, separating hood skin from hood brace was accomplished by first drilling out all spot welds, then cutting the brace across the rear as described, and finally using a heat gun and a spot weld chisel to remove the "caulking" holding the hood to the frame. Installing the hood hinges provided handles for pulling out the brace once it was free.
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  #25  
Old 06-22-2023, 04:52 PM
schwemf schwemf is offline
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Continuing with my testing on the spare hood, I removed the rear portion of the brace as described above by both John and Matt. The remaining brace section came out easily.
IMG_20230622_145928020.jpg

I grinded a few of the spot welds on the hood skin outer edges, but stopped when I noticed that they didn't have sufficient penetration!

Then I used the spot weld chisel to initially get between the brace and hood skin. This worked, but resulted in some stretching of the fold-over as you might be able to see in the picture.

The problem that I see with cutting the brace where I did (as described in the prior post) is that any minor deviation when welding the brace back together will tweak the hood skin out of alignment. I'm not sure if I could hold the two brace pieces in perfect alignment while welding/gluing to prevent this?

Leaving the brace in one piece should avoid this potential issue, so that's my game plan going forward on the hood that I'm trying to save.
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  #26  
Old 07-06-2023, 05:08 PM
schwemf schwemf is offline
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Removing the hood skin from the brace was the right move! I am so grateful to everyone's advice!!

On the hood I hope to save, I was able to separate the two without having to resort to cutting the brace, although I did some damage to the hood skin when it folded as I used hand pressure to separate the two. The 50-year-old caulking had glued the hood skin to the hood brace, and it was especially abundant at the rear of the hood, which is where the skin folded.
IMG_20230704_130751609.jpg
This job took me 13 hours, plus some more hours removing all the old caulking from the hood underside in preparation for hammer and dolly work.

Now back to the metal finishing.

I've been approaching this as you might eat an artichoke, going after the big problems/dents and working my way to the smaller.

After seven hours of bumping up the lows with a dolly and on-dolly work with a slapping spoon, the waves are smoothing out and the oil-canned area has "tightened". I believe this tells me that I had done too much shrinking. There's no way I could be stretching the metal back into shape without full access to both sides of the hood skin.

The work ahead of me is daunting, as there's damage over every inch of the hood skin. Now that I have access to all of them, it's just one dent at a time.
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  #27  
Old 07-07-2023, 07:18 AM
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drivejunk drivejunk is offline
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Your June update slipped past me, oops. This looks promising. I'm glad you have found an applicable plan to proceed with one way or another, and wish you good fortune as you follow through. I have a 75 Bronco project currently undergoing major surgery, keeping old firewall and bed floor but not much else. No matter how far one advances theres always another project around the corner which tests the boundaries of one's ability. Meet the challenge but enjoy your work.
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