Hi, I'm pretty new to MIG welding, and using a Hobart Handler 140. A goal that I've set for myself is to be able to butt weld 2 small pieces of 16 gauge or 18 gauge steel without warping pieces, and without clamping.
I start with 2 pieces of 16 gauge mild steel, each about 2 inches wide, by 5 inches long. I clamp them onto a flat surface, and align them along their long edges, and tack the top and bottom.
Then, I unclamp and start "subdividing" by tacking in the middle, then half again, then half again until my tacks are about 0.75 inches apart. At this point, the 2 pieces are essentially flat. All is well.
Then, I weld the first 0.75 inch long section (usually about 2 inches from the top edge, but I've tried it all kinds of ways). I get a good weld, but then as the metal cools, the piece starts to warp. It both "folds" a along the welded edge, as wel as "curls" in the long dimension.
The more sections I weld, the more I get this effect, even if I never weld 2 adjacent sections one after the other. The more time I wait between welds, the less distortion I get, but the bending/warping seems inevitable. I've tried waiting up to 15 minutes between each 0.75 inch section, and it doesn't help much.
My questions are:
1. Is it possible to butt weld like this without clamping, and without introducing distortion?
2. If so, how?
And, related:
3. If I'm welding in a small replacement section in my car, how do I cope with this sort of distortion, when hard clamping may not be possible?
I start with 2 pieces of 16 gauge mild steel, each about 2 inches wide, by 5 inches long. I clamp them onto a flat surface, and align them along their long edges, and tack the top and bottom.
Then, I unclamp and start "subdividing" by tacking in the middle, then half again, then half again until my tacks are about 0.75 inches apart. At this point, the 2 pieces are essentially flat. All is well.
Then, I weld the first 0.75 inch long section (usually about 2 inches from the top edge, but I've tried it all kinds of ways). I get a good weld, but then as the metal cools, the piece starts to warp. It both "folds" a along the welded edge, as wel as "curls" in the long dimension.
The more sections I weld, the more I get this effect, even if I never weld 2 adjacent sections one after the other. The more time I wait between welds, the less distortion I get, but the bending/warping seems inevitable. I've tried waiting up to 15 minutes between each 0.75 inch section, and it doesn't help much.
My questions are:
1. Is it possible to butt weld like this without clamping, and without introducing distortion?
2. If so, how?
And, related:
3. If I'm welding in a small replacement section in my car, how do I cope with this sort of distortion, when hard clamping may not be possible?