What amperage range to use during TIG Welding Aluminum?

One important rule for choosing proper amperage for TIG Welding Aluminum is to use 1 ampere for every thousandth (1/1000) of the aluminum thickness.

For example, to TIG weld an aluminum piece that is 1/8 inch in thickness would require 125 amperes.

However, as the thickness of the base material is higher, the above rule is no longer correct.

If you weld a 3/8 inch piece of aluminum, you only need a power source of 280 amperes (not 375 amperes, as per the rule).

Also, the amperage also depends on the type of joints.

For example, a T-joint would demand a higher power source than a Butt joint, because:

• In T-joint, heat can flow in three directions,
• While in the Butt joint, heat flows in two directions only.

To set the desired amperage, you can:

• Make use of a foot pedal or fingertip
• Rely on your TIG Welder by changing AC Balance (increasing EN), or setting AC amperage independently (if allowed by the machines).

Below is an Amperage Chart for your reference

TIG Welding Aluminum Amperage Chart