Repairing crack in 3"x3"x3/8" tube?

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I was at the metal store earlier today, picked up 20 feet of 2x4x3/16" for 64 bucks  on my way out I saw their "scrap" pile. They had a 3x3x3/8" tube about 59" long. I asked him how much and he said ''I'll give it to ya''. So of course I took it :P Also got 24' of 1.25x1.25x3/16" angle for 7.20 otd. Anyhow, when I brought the tube home I saw there is a crack in one side, propagating about 1/2" to an adjacent wall too. Can I hit it with the torch to gouge most of the crack out, grind the slag out as best I can, and lay a few deep beads to fix the wall? It looks like something HEAVY fell on one side, as their is a pretty deep dent/gouge on the side that's cracked. It's cracked 28" from one end. The plans I had for this tube was for an engine hoist telescoping boom (the inside piece). let me know, and I'll post a pic tommorowLast edited by JohnR; 02-05-2007 at 10:43 PM.
Reply:If you fix the crack up well, and you are trussing the thing up anyway, it should work. Since it was free, it can't hurt to try. Just test it out with a full motor before you get silly and stand under it....
Reply:Of course. I went outside and remeasured it. 3 5/8" side wall to side wall, 1/2" wall thickness. Guess I have to buy some 2.5" square tubing, at least 3/16" wall for the extendable boom. Interesting side note, on the Passport, it has a color-coated voltage knob. Basically, you should only run the voltage on 7 out of 10 on 120v. I was thinking to myself, should I try it on 10? I figured the worse that could happen was a tripped breaker. Nope, but with a definite increase in heat. Is it possible to draw >34(?) amps off 110? My 10/3 100' extension cord didn't heat up though, so who knows. The crack only went about 1/4" deep, with most of the spiderweb less than 1/8" deep. So I took anything I was questionable about out, welded it all up, then ground it smooth.
Reply:Post moved to proper forumLast edited by MJDamiani; 02-06-2007 at 03:36 AM.
Reply:Moved to proper forum Attached ImagesLast edited by MJDamiani; 02-06-2007 at 03:40 AM.
Reply:That's fine, mild steel is very forgiving, you can do just about anything you want with it. Dave