One day... I want to have a real shop, and begin some actual work on my 36. Until then, any chance to work some sheet metal is 'practice'.

The latest practice, is to make some chain guards for the machines at work. Dirty, nasty location, they don't have to be pretty, and I'm not trying to make them perfect. Just good industrial quality guards, hopefully about 10% better than most of the chain guards you would see.

Unfortunately, the only steel I have at my disposal is some 20ga galvanized. Now, welding galvanized presents some intresting troubles. Causes the MIG to splatter, generally fouls the weld, and of course: it's deadly. SO.. I keep the fan to my back, and hold my helmet as to create a clean air draft into the helmet to displace any of the fumes.

anyway.. I have some questions for ya. my guards always seem to warp, and the top of the guard becomes convex from the shrinkage around the edges. Would this be eliminated if I were to induce some bend into the face before welding? If I started with it concave, would the warpage cause it to be flat when done? Is it better to try to shrink the metal in the center after welding?

Not that it matters for the guards. No one really cares if they 'hump' up a tad, and I actually like the look. BUT.. the day will come when I have to make something which actually has to be flat. I'm pretty sure that if I were to spot weld instead of continuous bead weld it wouldn't happen. But, that makes for a weaker joint, and I like full welds when joining pieces.

From my experience, warpage is the biggest problem to welding steel.

anyone got tips? Thanks