Q. I am in the process of restoring a 1948 Dodge panel truck. The driver side door skin has damage along the hinge side. The damage starts just below the top hinge and continues to the bottom of the door. The area was previously repaired with lead before I purchased the vehicle. The lead was cracking and had low spots, so I decided to remove the lead to see what was underneath. I found a gouge that started out about ¼-inch deep x 1-inch wide and tapered to a V as it continued to the bottom of the door. It is in an area of the door that prohibits hammer work from the inside of the door, so I began heating and using pry bars on the inside to raise the gouged area.
After working with the door for several hours I have about 60 percent of the damaged area raised, but all of the work is very rough. I found several small pinholes in the skin that were made during the original repair work, and the damaged area appears to be very thin metal. I have a donor door that was included with the vehicle, and I’m thinking about using part of the skin to make a patch. The donor door is from a 1950 truck, and has a good outer skin, but the interior panel is in bad shape. Would you suggest using a large portion of the donor skin to repair the door, or only use enough of the skin to patch the damaged area? Would having a vertical seam about 8 inches from the hinge side of the door cause any problems if I only use a patch to repair the skin? I have enclosed photos that show the damaged area and my work to date. Thanks for any advice you can give on this repair, and thanks for all the great articles you have published.
Via the Internet
A. The general idea is to place your welds where you have the best access to work them. While you could splice in a small panel, working a vertical seam on a door skin is a pretty difficult job – it’s hard to correct the distortion from welding.
I’d say the best place to splice in a new panel is in a horizontal line, ideally close to one of the more highly contoured areas of the door, like I’ve shown with the dashed line on your photo. This is presuming you have good access from the backside. If your access is partially blocked there, you could move the seam down as much as necessary. I’d really try to avoid having a junction between a vertical and horizontal welded seam, if at all possible. That’s always a nightmare to get straight, since the distortion from welding is always accentuated in a square corner!
Q. A friend and I attempted making some work stands, using brake drums as a base. We MIG welded a steel disc to the drum, and the welds cracked instantly. I tried using some ER 70-S2 rod with a TIG welder, and had better luck, but some of the welds still cracked. I’ve always heard you’re supposed to use silicon bronze rod when welding steel to cast iron, but really haven’t had much need for this in the past. So, I tried TIG welding with silicon bronze rod, and it seemed to work fine. Do you think those welds will hold?
Via the Internet
A. TIG welding cast iron is always difficult, but I’ve had the best results by using bronze filler rod. I’m not sure how structurally sound such a weld is, but for a work stand, I’m sure it will be fine!
Structural welding on cast iron is probably best done by straight arc welding with a high-nickel content rod. Some people gas-weld cast iron with good results, using a special flux and cast-iron rod. Surprisingly, this can make a good weld, but you have to take precautions to cool the weld very slowly (by burying the part in a container of ash, for example) or the weld will crack as the cast iron cools. An alternative technique that helps to prevent cracking is to weld small sections, and then peen the weld with a hammer as it cools.
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