200-amps is a good basic Mig welder to have. I ran this weld at 224-amps, 29-volts. With Lincoln's
.030" L-56 Mig wire. You're not going to see that kind of penetration with a 120-volt Mig welder.
Shield Arc, that's one picture perfect weld you did with that Lincoln.
It's no wonder that it took 20+ hammer blows (if I remember right) to break one of those, when you did those hammer tests a couple years ago.