Correcting distortion in an angle iron frame.


What is the best way to correct a crooked leg.
I'm welding 30 x 30x5 mm angle iron with an arc welder.
I have cut it and bent it back, then welded it but it didn't come in
enough. I'm going to cut it once more (without bending and do it again.
The reason I got into this mess is because I had an experienced welder
showing me how to weld and he said "that's a bit out but you'll never
notice"... and beyond that we concentrated on the lesson but forgot to
put the square on it. One section at the top was 10mm longer than it
should be and I've had to cut it.
I'm wondering how professionals get accuracy as it seems a hit and miss
process.
My structure will fit on a deck and have glass on two side plus a base
1110 x 800 x 350mm.
Thanks John
Reply to
John
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Cut it, move it until it's correct, clamp it very rigidly. Use tiny tacks to hold it together, placed so as to oppose each other's warping force. Remove clamping, recheck, iterate as necessary until it's square when tacked.
Then sneak up on it - weld a bit here, stop, weld somewhere else, stop, until it's done.
This comes under the heading of fitting and it's why fitters make a lot more than welders.
Grant
Reply to
Grant Erwin
Thanks for that Grant I was wondering about the skill level. Being only 30mm means it's a small target. It is near 90 degrees one side but the other is out. I weakened it so I could bend it, I braced it (tacking) and welded from the heal to the toe and have a hole at the toe! It still bent. John
Reply to
John
"John" wrote in message
Study the leg to determine which direction it should move, fire up your torch as normal, grab the leg and attempt to move it in the desired direction and keep the pull on till later. Don't back off but not a lot of pressure is needed either. Heat the thickest spot on the side that is under compression until the area is just red and remove the heat maintaining the pressure on the leg. As the spot cools off the leg will move as you direct. If it didn't go far enough do it again, maybe a little more aggresively if you dare. This is the magic art of 'flame straightening' .......... phil kangas
Reply to
Phil Kangas
First rule of frames. Tack everything before you weld anything.
Then tack temporary diagonals on to keep the frame honest while welding.
Reply to
Ernie Leimkuhler

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