Welding thickness amp settings

[Mad-Dax]

I have a question on tig ac for aluminum and using roughly 1 amp per .001 inch. I would use 118 amps for 0.1181 or 3mm? Correct?

However that seems like a lot because I was practicing with a 3/32 2% thoriated electrode with 70 amps on 3mm aluminum and I would melt through unless I went really fast.

[performance]

This is one of the problems that exist when companies try to give "standard" recommendations when welding, especially tig. It is my opinion that this formula is not even slightly accurate.

Adjust the amperage where you feel certain you are reaching maximum penetration without overmelting the metal, balling the tungsten and burning through.

Several factors affect these "standard" recommendations.

The following 5 standards that affect operation are found in Larry Jeffus's Welding and principles 6th ed. and can also be found in many technical publications related to welding and prove the point that this kind of info is bogus.

The factors affecting welding amperage recommendations.

1) Voltage to machine is exactly correct
2) Cable leads are very short.
3) Excellent connections, not loose or oxidized
5) Perfect arc length.

Welding does not depend upon amperage alone. The main goal of welding is to have a total number of watts to weld. It is wattage that creates the weld pool.
To find wattage, multiply output voltage x's amps. A welder with a low OCV may need higher amperage to weld the same as a higher OCV machine.

If you need a guide, a more broad guide of about 70-85 amps for every 1/8 inch of material might be better for general work. Aluminum will take more amperage on AC that steel will on DC.