Try this once:
Take a 10mm steel rod and make it a bit pointed. Tack it to a thick steel plate. Ask someone to grab it at the top, not too close of course. Then at full amperage quickly run a bead around it. I'm sure you'll get a surprised face as a reward. I did this and the guy started laughing. The rod wagged like a dog's tail.
Try to lay the two pieces close at the end you start welding, and with some space between them at the other end. When you get this right, they will meet each other as you get to the other end. Then they will contain less strain than if you tack them. When you tack them they will not be allowed to contract and that leaves you with more strain in the finished material. And if you have to grind off a lot of bead after you're finished, you have put in too much metal and thus heat, try with less the next time.
Go buy this book: "Modern Welding" Althouse, Turnquist, Bowditch, Bowditch. ISBN 0-87006-668-4.
It's not cheap, but the best coverage I've seen on welding. Also covers soldering and brazing.  |