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Discussion Starter · #1 ·
Heres my first weld. Looks like it needs alot of work. Is it OK to grind down the weld and set another bead? I have many holes after grinding.


WELDER
Lincoln 175 HD
Wire speed 2.3
Heat Low
Using gas
 

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Do you have a pic of that which is expandable? What is that of?
 

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It is very hard to get a sheet-metal welding bead that doesn't have any holes. Why? You shouldn't be laying down a continuous bead, as the metal gets too hot and then distorts. I've always had to go back after grinding the welds flush and plug the holes left over.
 

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Discussion Starter · #5 ·
So I can expect to spot weld every few inches and then, after grinding, fill the holes?

Than, I guess, grind again?

There is a some warping now, can that be hammered out?
 

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The best procedure for a butt weld is to tack the seam, then go back and tack again. Keep doing that until you pretty much have formed a continuous bead. If you try to lay a bead on thin sheetmetal, it'll warp. You also need to grind off the EDPM coating on the patch panel where you are welding, it's burning off and contaminating your welds. Only clean metal welds properly.
 

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Hemi and Midlife are correct. You do not want to concentrate just in one area or warpage will happen.

For example: If you were welding say a 12" section, tack it together every 3" dividing it into 4 sections. Then put a couple tack welds in the 1st section. Move over to the 3rd section and add a couple tacks there. Repeat this now into the 2nd section and finally the 4th section. Repeat this again starting back in the 1st section and continue until the gap is closed up in all 4 sections. Grind down and clean up looking for holes to comeback and fill in.
 

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Discussion Starter · #8 ·
I got'cha, I'm going to attempt it once again with the above suggestions. One more question....How do I get the worping out of my old panel?
 

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To remove warping, you can use a shrinking hammer, which takes a lot of skill.

You can cut the welds, use a dolly and hammer to get the metal back to its original shape, and then shape the edges so that you have a nice 1/32" gap where you're going to weld. At best, a one inch bead may be accomplished without warping, but you need to be quick and using 0.025" MIG wires.

If your warping is not on the exterior metal, it's probably not worth worrying about, so long as it fits to its neighbors and parts can fit onto the metal.
 

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I've also found you just can't go tacking everywhere. You have to grind down first (Watch out for surrounding metal!!!) Once the welds get close together, you start putting the new welds in the middle, whcih are actually on top of the other welds. So when you grind it down, there goes your weld, and you're left with the original hole.. Happened to me when I just kept tacking and tacking.
 

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To remove warping, you can use a shrinking hammer, which takes a lot of skill.
Actually this would be the reverse of what you want to do. After welding, hammer on dolly on the weld. This will stretch the area back to its original shape. Welding causes shrinking so you want to stretch it back. Do not hammer around the weld, hammer on it, but don't go crazy on it, just enough to bring it back flat. If you do happen to stretch an area too far(any area), use a shrinking disc on a grinder, not a shrinking hammer. Shrinking hammers don't work well, they just chew up the surface. A shrinking disc at about 6k rpms then cool the metal. You should hear a quench, if it doesn't quench it isn't hot enough. The metal should not turn blue. Hopefully this helps.
Grant
 

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Discussion Starter · #12 ·
Since the weld and the warpping is on the bottom half of the cowl, it won't be visible.

Anyone herd of using a little filler to smooth the warped and welded area? Im concerned about rain water running down the cowl and catching in the pockets of my uneven weld.
 

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I Hear ya with that concern too. And afters, pour some water in (Without the top on. If they are like my repros, the water pools around the hats anyways.. You could get super anal.. I myself pounded out what i could, Zero-rusted it, and called it a day.. I didn't bother with filler in there (My welds didn't need it though, but I probably wouldnt' have even if they did. Something else to go wrong in there). I think you'll be fine.
 
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