How to Tig With Thick Aluminum

Clean and prepare the aluminum with acetone cleaner, water and the stainless steel brush. Unlike steel, even if the aluminum looks clean and brand new it is not. Make sure you do not use the stainless steel brush you use on aluminum on any other metals.

Grind the electrode to a point using the grinder.

Choose the correct electrode and filler rod. Use the smallest diameter tungsten for the amperage you are using. Use a 1/16-inch pure tungsten for 30 to 80 amps; a 3/32-inch pure tungsten for 60 to 130 amps, and a 1/8-inch pure tungsten for 100 to 180 amps

Insert the electrode by unscrewing the tip of the torch and sliding it into the collet.

Establish an arc using the correct flow of current and gas for the desired weld according to the documentation that came with the welder.

Create the weld puddle. Hold the torch at a 90 degree angle to the aluminum for a butt weld, centering the weld pool over the two pieces. For a lap weld, hold the torch at a 70 degree angle forming the pool of the overlapping piece and the flat piece so they flow together. For a T-joint, use a 40 degree angle on the torch to direct more heat to the flat surface. Finally, for the corner joint, hold the torch at a 90 degree angle forming the pool across the center of the two pieces.

Add the filler metal dip into the puddle while pushing it along the metal.

End the arc and leave the torch over the puddle to protect it while it cools. Make sure the electrode does not touch the weld pool.