Welding Stainless Steel - shielding gas question

[Matt@RFR]

What David experienced was the result of changing gas without changing settings, more than likely. Straight gases, dual and tri-mixes will all run on mild steel fairly well, but will all require different voltage and wire speed settings. There is no argument here...just tuning required.

And CM-67; There's no such thing as an 'optimum' anything in this field when used in a global context such as you put it. The gas you mention (which is simply a trade name...why not state the percentages of each gas?) may work great for you, but garunteed somebody somewhere will be able to use a different blend with more success.