It was rusted out pretty badly on the bottom, and the platers couldn't do anything with it. The black spots around the crank hole are actually perforations, i.e. holes through the metal. The rest of the bottom was crusty as well.
The top end was in beautiful shape. I made up a flexible shape pattern from tape. I'll tell a bit of a story on this, in case some of you haven't done this before. Wray Schelin teaches this in his classes, and I believe he was the pioneer in doing a flexible shape pattern like this. You need low tac graphic artists' tape, sort of like masking tape, but has low tac so you can peel it off easily without tearing the pattern apart. You put one layer of tape on the object, and overlap it ever so slightly, maybe as much as an eighth of an inch.
I use a carpenter's pencil or a sharpie to highlight all the body lines, etc. onto the tape. IT will show through the fibreglass tape afterwards, and will not rub off that way.
I use a razor blade or a file to cut the tape around the edges, to remove the excess.
After the first layer of tape, I used two layers of regular fibreglass packing tape. This stuff will not stretch, so it holds the shape of the object very well. You put the first layer on, 90 degrees to the layer of graphic artists tape, then the second layer of fibreglass tape is rated another 90 degrees. You can get away with only one layer of fibreglass tape, but it sometimes will come apart on you in use. The edges are cut off the same way, with a razor blade or a file.
Then very carefully peel back the tape pattern so as to keep it all together. You don't want to pull the layers of tape apart, which can happen if you get too aggressive. Once it is pulled of the object to be patterned, you put a little powder, like baby powder to remove all the "tack" on the back of the graphic artist's tape. That way, when you place it on the metal you are working on, it won't stick to it again. You use this pattern to test the "fit" of the new sheet metal as you work it, and pound on it, to make the new shape. This method works very well.
Here you can see that the flexible shape pattern has the shape of the old piece, so you can now use it to make the new piece.
Okay, I screwed up here, cause I didn't take any pics of this while I was pounding it out. I also made a buck out of a couple pieces of hickory. I bought a 4 foot long short at Windsor plywood, and laminated them together so it was two inches thick, then carved the shape out of it, using the flexible shape pattern to make it. Used a round over bit in the router to make the top edge consistent shape all the way around, and then sanded and planed and filed it so that the flexible shape pattern fit it like a glove. After that, I screwed the back edge of the new piece of sheet metal to the back edge of the hickory buck. Then screwed another piece of hickory on top of it that fit around the front edge of where I would be pounding it over the hammer form. For those that haven't used a hammer form before, you need to do this so the sheet metal doesn't just "lift" behind where you are pounding it down over the rounded over part of the hammer form. There were many hours of hammering and tapping so as to shrink the metal around the outer corners. That was the hardest part of the whole operation. You can see in subsequent pics, how the new sheet metal is quite rough here and there, but it all gets planished out in the end.
Here is the new panel, tack welded in place. I use the mig to tack it, then grind off the tops of the mig tacks flush to the surface, then tig weld the whole shebang up, in increments. Weld a little, grind a little, weld a little, grind a little, etc. so as to not get too much heat into the panel. This had very little warpage once it was all welded up.
Here you can see it is welded up a few inches at a time, then I use a 3M green corp grinding wheel in a die grinder that is 1/4 inch thick to grind down all the weld, flush with the surface of the panel. This particular panel is gonna be bondo free, i.e., it has to be perfect as its going to the chrome shop afterwards.
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And the finished product, once welded, ground smooth, and the whole thing metal finished. It was a lot of work, but it turned out very nice.
I had to make up a dimple die for the crank hole. I used half of a set of dies that James (W.Canada) sourced for me, and I made the other half of the die from pipe and stuff. Don't have any current pics of the home made piece.
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