Judging by the comments so far it appears i will have a real easy time when i finally start using the 'right' stuff because ive welded a fair amount of thin sheet metal with a 90a harbor freight flux core machine they used to sell for $89, with flux core wire of course, and i've never run a wire thinner than .030 and recently did some welding on a sheetmetal gas tank with .035.
Many of the older cheap machines did not have enough adjustment range to go low enough to weld thin steel. But high quality machines did.
I think that's the main factor. Who has a nice machine and doesn't know anything about welding? Oh boy here come the jokes, but i mean anyone with a welder that has good adjustability almost certainly knows enough about welding to not be asking the question.
I know it was always the main problem with that $89 HF flux machine. Me being an automotive instructor who teaches electrical, I came up with a pretty cheesy solution... just add resistance to the ground until it won't arc any more, then back up a little. If you have a fairly large piece that's not clean, you can do that pretty easily just by moving your ground clamp further away or onto worse surfaces. Doesn't work if the workpiece is small and clean.
Since I already have them, i use automotive jumper cables for this, in between my ground clamp and the workpiece. You're just adding a bunch of wire into that ground path. A pair of jumper cables has two wires which can be run parallel (least added resistance), using only one wire (medium added resistance) or in series (highest added resistance), so you kinda have 'settings' from moving the clamps around.
You do still have to stitch weld instead of trying to run continuous beads. Getting a feel for the heat of the metal that's NOT glowing is how you stop (ok, greatly reduce) blowing holes through thin metal. Even when I do blow a hole in something thin, I can always close it right back up with the welder as long as i am going slow enough (letting it cool enough between short welds).