[WelderDan]

If I want to fillet weld, say, a 1/2" peice of mild steel to a 1/4" peice of steel, should I "direct" the rod toward the thicker peice? And what are recommended amp settings?

[Coldman]

You don't say what type and size rod you wanna use.

[WelderDan]

How bout 1/8 7014 or 1/8 6011

[tweake]

i can't say amps, however you want to be hot enough to melt the thick steel well which means your going to be to hot for the thin steel. you counter that by directing the arc onto the thicker piece and wash over onto the thinner piece.
how much depends on the difference in thickness, type of metal etc.

the other trick is to put a heat sink on the back of the thin piece, like a bit of aluminium, and then weld it like normal.

[WelderDan]

i can't say amps, however you want to be hot enough to melt the thick steel well which means your going to be to hot for the thin steel. you counter that by directing the arc onto the thicker piece and wash over onto the thinner piece.
how much depends on the difference in thickness, type of metal etc.

the other trick is to put a heat sink on the back of the thin piece, like a bit of aluminium, and then weld it like normal.

That's pretty neat. It's good to know for when I pull junk out of my scrap heap for practicing on. It probably explains the various results I've had in practicing. Here's a 1/2" railroad track nail that I welded to a 3/32 peice of metal -- some kind of flat(ish) tubing...e7014...I actually wasn't thinking about differences in metal thickness, so maybe I got lucky

[cj737]

Amperage with stick rods are mostly set by the rod size and type as labeled on their box. Whether a single pass is sufficient is dependent upon material thickness and prep. Normally, concentrate the heat on the thicker piece and wash over to the thinner piece.

[WelderDan]

Finally started getting some decent 7018 fillet welds by directing the rod more toward the thicker (and rusty) peice. What a cool concept