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Discussion Starter #1
I saw a site where someone was fashioning body panels out of scrap metal from junk cars to install where rust had been ground out of a car body. This makes sense to me as the thickness of the junk car would be about right. It would be cheaper (FREE!) and more available than buying sheet metal of the right gauge from a supply house. But...what about bending a flat piece to fit the curve of the GT body? Does it need to be slip rolled first or can it be bent into place as it is tack welded into the prepared hole? Anybody ever used a trunk lid to make a fender patch? I´m tempted to try it but would like to know if there are pitfalls that can be avoided first.
Thanks,
Tom
 
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You don´t need to start with old sheetmetal, and in fact it will probably be easier to start with non-rusted, virgin sheetmetal. Also, some newer vehicles use high-strength steel which is very brittle and does not lend itself to formability. I´d actually recommend going up in gauge thickness, just to provide better strength and rust resistance in the future. And a 4x 8 sheet of 22 gauge is only about $35 or so. Regarding fitting the curved sheet metal, it´s usually best to pre-fit the patch panel prior to welding, so there is no undue stress to the metal. While it would be nice to have access to all the equipment all the time, I realize this is not the case for most. But much can be done with hand tools and patience.

In fact, just last weekend I made numerous repair panels for a friend´s F350, using nothing but a few plastic mallets and a t-dolly to form the metal. I did not have access to my bending brakes or forming equipment, and had to make due with what was available. The fanciest equipment I had for this project was an electric hand shear and a leather shot bag.
www.74ghia.com/f350/index.html shows the rebuilding of the lower front cab corner. This was done over a Saturday. All pieces welded in place were back-coated with POR-15 prior to being welded to reduce the chances of future rust-through.

Bob
 
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WOW, Bob, that was an ambitious project for a Saturday. Nuff said about recycled metal. You have convinced me that new metal would be better. I have heard of using shot bags for shaping metal and I even found one for sale on someone´s web site for $60 (no shot included) but no information on how one would use it nor what shape it is when filled. Is the shot bag placed on the bench and the cut sheet metal tapped over it as if the shot bag were an anvil? It looked like the unfilled shot bags were just very short cylinders of 12" and 16" diameter but I couldn´t be sure. That doesn´t seem like the ideal shape to me but having never used one or seen one used, what do I know?
As many rusty Opels as there are out there perhaps you would be willing to do us a photo set on how to prepare and patch a typical rust spot using low tech tools such as a shot bag and plastic mallet. I, for one would be greatly interested. I´m sure it would be a big help to a lot of other newbies to restoration like myself who aren´t interested in concours quality work but something they can do for their car in the garage on a Saturday.
Thanks again,
Tom
 
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Yea, I admit the job grew into more of a chore than originally anticipated. My friend said it was *rough*, but once I started cutting layers away, I realized the only solution was to reconstruct all three layers from scratch.

Regarding the shot bag: Mine I have filled with lead birdshot. I prefer this to sand, which many people use. It is heavier, and does not displace as easily when struck with a mallet. It took three 20 lb bags of shot to fill mine. The shot bag is used as a controllable support for stretching metal. If you struck the metal unsupported, you´d stretch it in an uncontrolled manner, but the lead shot allows the metal to be *moved* gradually, so it doesn´t distort.

For the rounded corners of the sheet metal, I used a t-dolly, which is a homemade tool that is simply a piece of 1/4 inch x 1.5 inch steel welded to round bar stock (I have various diameters to make different radiused edges) in a *T* shape. The flat stock is clamped in a vise, and the sheet metal is placed on the round bar stock, and hammered lightly until the proper curved edge is attained.

An anvil is a great tool as well, but not always necessary. That, plus a good one is hard to find, most are cheap iron and not that good (you can tell just by the sound of it). I stumbled into one that was being given away, it was made in 1897! I found out the thing is worth about $1200 or so. For the cab corners I repaired in those photos, I used the edge of a metal counter to form 90 degree bends, and a slapper bar to bend it (just a piece of oak I cut out to strike metal with). Avoid using metal hammers to shape metal, plastic and wood hammers work better at shaping metal without distorting it too much. Use the metal hammers for the fine detail work.

I´d love to document some of my various projects, but at this time I can´t transfer them to jpg format. I just got a digital camera, then found out my computer isn´t capable of handling the software! So I´ll have to wait until I can update it. You can thank the owner of the truck, Diane, for taking the photos and posting them to her website.

Bob
 
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