Mig -- importance of a good ground.

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I was practicing welding thick to thin today using my MM252. I'm using 75/25 mix and .023 wire. My starting settings were as recommended for 3/16 steel was 20v & 480 IPM. That's the highest they show for .023. As I was welding, the wire was erratically sputtering in, and popping back, even though the weld was barely acceptable. The area  being welded was spotlessly clean. Since it was not giving me that clean smooth frying sound,  I knew a setting adjustment had to be made. So I adjusted to 20v/400 IPM. When running the bead again I got that smooth frying sound I was hoping for. But there was still something wrong, I thought. Miller is usually very accurate with their recommended settings. I must be doing something wrong. So I checked my ground which was poor, and disconnect from the table and hooked directly to the small piece being welded. I was able to go back to the original 20/480 settings getting that smooth frying welding sound I was supposed to have in the first place. The importance of checking the ground and rechecking can not be over emphasized. I learned something new again. (Always learning, always forgetting.)Miller Bobcat 250Syncrowave  200Millermatic 252Spoolmatic 30ASpectrum 625 X-TremeMaxstar 150SVictor O/A torchesDewalt angle grindersWelded on/off for over 40 years.
Reply:I always ground directly to the workpiece. My table is made out of pieces of flat stock (150mm x 15mm thick but flat stock anyway) and I didn't bother to grind the mill scale. The spatter doesn't stick to it but the downside is that it doesn't make a good ground at all.So I always ground the work pieces.Mikel
Reply:On 99% of the jobs I've been on.... When the QC or the Safety person walks into your work area they expect to see both welding leads and the ground attached within a few feet of where the actual weld is taking place. The risk of frying a PC board on a piece of process equipment or heating up a bellows expansion joint is a big concern.Lincoln SA200's... at least 15 - 20. They come and go. Growing partial to the "Short Hoods" in my old age. Last count on Short Hoods was 13 in possession.