The Stovebolt Site Forums The Shop Area Paint and Body Shop '59 Apache - Inner/outer cab corners, first time

Hello!

Recently picked up a '59 Apache. Truck is from Nevada, so the body is relatively rust free, except for the cab corners. The PO gave me brand new inners, and the outers just arrived. This will be my first body panel replacement, and I have a few questions -

This is not my first time welding, although it is my first time welding sheet metal, and doing a body panel replacement. I'm using a 120V Lincoln mig welder w/gas 80/20 gas, and I've been practicing for several hours on 18ga sheet metal using panel butt clamps that hold a .040 gap. I'm using very small weld spots...just touching the wire to the gap for a second. I build a line of small welds, about 3 at a time, equally spaced across the joint, and let the metal cool to the touch before I weld again. I do that until I have a solid weld bead that I can grind smooth.

At first, I warped the metal...not at where the metal butts up, but futher down the sheet...it developed a "bow". Paying careful attention to heat, and using a body dolly to keep the sheet straight has helped a lot, made a few perfect welds, is there anything else I can do or any secrets to help prevent warping?

Also, this will be my first time cutting off a body panel...I plan on doing small sections at a time with an air driven die griner with a 3" cutting wheel, drilling out the spot welds with a 1/4" dril, and using an air chisel if necessary to help break any stubborn welds.

What are the watch-outs when cutting off a body panel? Yes, I removed the gas tank, and I can get at 90% of both panels from both sides.

Last - how much bondo should I expect to use to finish it off? I'd like to keep it to as little as possible to avoid cracking.

I'd appreciate any advice that anyone can give me to help the job come out as best it can.

Thanks...

Chris

What I do for welding butt seams is to place small weld spots widely spaced, and some in between until I have a line of them about 1" apart. Next I weld to the side of each one and let it run into the previous one. Eventually the spaces will come together.

The bondo will be a function of how much you need to cover up.

Most of us learn by doing so it looks like your already on your way to becoming a pro. You didn't mention what size wire your using? I use .023 in my mig. I've found that the tighter the "fit" or "butt" weld area the better the welds turn out. It looks like you've got a handle on welding, spaceing the welds and keeping the heat under control is crucial. Hammering and dolly work are just a part of the process. Bondo will not crack, unless its applied to thick. Good luck with your project.

I also use .023 mig wire when I'm welding sheetmetal. Spend the extra time on panel fitment, when you butt weld try to have tight gaps. If the metal is slightly touching that's great. Your gaps should not be wider then the welding wire.

If you want really nice metal finishing with minimal use of filler you need stretch that metal back to its original state. Don't wait to finish your bead to do it either its that much harder if you do that. You tack it in, grind your welds hit the haz(heat affected zone) with the hammer on dolly. The haz is the area where the metal changed colors from the heat. Then tack new areas grind your welds hit the haz with the hammer on dolly. You do this until its completely welded in. Now if you don't have access to the back you just tack and grind and keep the metal cool as you can.

Some people like to flange one of the edges to make it less likely to warp. I just bought an air flanger so I am going to try it out.

Someone was telling me that they glue them on these days, instead of welding. I think it is suppose to keep it from rusting as much. Anyone else hear of this??

I like to use the flanger whenever possible but it won't work well on curved surfaces. I try to place the offset about 1/16" from the other edge to leave a small channel to weld into. That way there's less weld material to grind off. If it's a curved surface and the back side won't be visible, I sometimes cut a narrow band of sheet steel to back up the seam and prevent blow-through. Otherwise, it sounds like you're already doing everything I know to do. You'll only have to use enough bondo to smooth everything up so you shouldn't have any problems.

It can be done with a lap joint but I never use them. I only put lap welds were the factory had them originally. You can not do really good metal finishing with a lap welded patch panel. You have to use filler and I try to use as little filler as possible. Butt welding is the best way, but a lap weld will work.

Thanks to everyone for their comments.

I'm using .025 wire. Have been practicing some more, should be ok. Seems like the key here is take your time. Weld, walk away. I've also developed an appreciation for just how much work this is...after removing the old panels, I have to deburr everything, and clean off the primer from the edges of the new panels so that I'll be welding clean metal. I found that any rust or paint makes it much more difficult to get a nice clean arc at the start, and it also seems to prevent the weld from penetrating. After cleaning I'll have to fit everything together very carefully. Seems like if I set up everything properly, the welding should be the easy part.

Well, we'll see how it comes out when I try some time next week.

Chris

Harbor Freight sells these as a set for $10 they make fit-up/alignment of these types of repairs much easier.
http://community.webshots.com/photo/2071953970102454676qiHynG

Brad -

Thanks for the link...already have the Horrible Freight panel clamps...best $10 I spent on this project.

Chris