When I first got my new Powertig 200DX I ran just a couple quick beads DCEN and then went to AC for aluminum ... (still a work in progress - learning curve) Today I switched back to DCEN and ran some beads, lap joints, butt joints and fillets with 1/8" mild steel ... man this thing is unbelievable ... fast, clean and quiet ... you CAN NOT break the joints I welded ... this is the best machine I own hands down ... Still haven't tried the pedal yet ... been doing everything 2T