Doing the body work on my 35. I did all my patch panels and roof. I am down to the back of the cab. My question is... the back of the cab is pretty pitted and is a little warped. Should I cut it out and replace with new sheet metal or is there an easier way to fix it. When i say its warped i mean it pops in and out depending on which way i push it. Here are a couple of pics. Any help is appreciated
There are methods for repairing that, but for the time and investment involved... I would probably replace it. Especially if you've already demonstrated the skill to patch other panels, and are happy with your work. What's one more? I couldn't tell from the rusty pic... but the only thing that would detour me from replacing it, is if the steel had a really killer belt line or other interesting features that I wasn't able to recreate. Even then... i'd be tempted to still replace the panel, and cut and weld the interesting stuff in and blend it smooth. Easier said than done, but much harder projects have been shown around here.
you can keep the ''oil canning'' from happening with either heat or a ping hammer. If your not familiar with shrinking metal with heat, you'd be better off using a ping hammer or a shrinking hammer and a dolly. pop it out where it stays and go over the whole area with your hammer on the inside and dolly on the outside. just do alot of LIGHT tapping with the pointy end of your hammer. you will see alot of high spots on the out side, but try to make it all even.this should stretch the metal enough to keep it from going in and out. And then your choice of filler is needed.
I would recommend blasting the rust scale prior to any work, patching or straightening... Sounds like you need to identify-relieve any dents to be sure all you have is some stretched metal then you can heat shrink. To heat shrink, I use a medium torch tip with a fairly tight flame and heat a small area "orange" about the size of a quarter, don't be alarmed if the metal grows or concaves a bit, you are loosening the molecules, then while it is still hot, grab a dolly and place it on the back side and use a body hammer on the outside and lightly hammer "on dolly" the hot area, use a circular pattern and hammer from the outside in, this should take 30 seconds or so and then quickly cool the area with air or water, this sets the molecules, I prefer air. The area will shrink some and may require additional hammer and dolly work to further repair, you may need to do this quite a few times over a large area. I would use a straight edge as a gauge to know when you are in general contour. If you were planning to cut this area out, you might as well practice shinking, you may save the panel or at least learn to do it for other panels you may need to save. Goodluck!
Thanks for all the answers. I think i will try to shrink it first. This is my first time messing with metal. Even fabed a few panels that I couldnt buy, including the belt lines on the top and bottom of the firewall sides. Get a lot more out of it doing it myself. Plus I have a bunch of new tools.
if you are srinking with heat just heat an area no bigger that a dime size then you will work it and then use a rag with water on it.Dave www.myspace.com/daveloweswr
This is the sort of situation where a shrinking disc is the perfect tool. Get it down to shiny bare metal. Determine where the high spot is, float the grinder with shrinking disc over it. Don't apply pressure, just the weight of the grinder is enough. Swing the grinder from side to side, if you watch the spot at an angle so you're seeing reflected light, you'll be able to see the crown in the metal rise. Do this until it's too hot to touch with a bare hand, then quench with a wet rag. Don't get it so hot that it turns blue. Experiment with the size of the area and the heat, like most things, you learn by doing. Hot shrinking is more fussy and easier to cause more damage with, the disc is very forgiving.
I gotta tell'ya......if you have no metalworking experience, you shouldn't be trying to fix this problem. It's one of the hardest sheet metal problems to fix...a warp on an almost flat panel! Did it start to warp when you were grinding the roof clean of the rust? If so, you're in big trouble. Was it there already? Did someone weld a panel onto the roof, it looks as if there is a weld seam visible? For a beginner, the easiest method might be to weld in new sheet metal. BUT! Be sure to get a big enough piece, and curve the sides to match the curves at the edges of the roof. That way you arent welding on a flat area. Weld it where there is a lot of curvature, you'll get less problems that way. Good way to try out some hammer and dolly work, too, to correct the minor warpage (if you're careful!) you'll get there.
follow secondwind raceing suggestion and it dont make any difference if the redbutton goes up or down do the hammer and dolly and and hit it with cold water I mark the loosest spots on the metal with a magic marker and pre plan my attack on the metal and check as i do each one and feel the metal as you go it will take many shrinks on some panels and you may have to return to some areas and almost overlap your old shrinks
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