tungsten prep for TIG Aluminum

How do you prepare the tip of the tungsten for TIG welding aluminum? I have been told there is a way to make the tip ball up a little but am not sure how to do this. I am a welder in the Navy and all we learn is Carbon and Stainless. Thanks.

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I usually dont do anything but put a blunt taper on it with a grinder and let it ball however it wants.

but if you want a nice smooth spherical ball on the tip of your tungsten, the best way I have found is to set the polarity to dcep also called reverse polarity. then...light up on a clean piece of copper with the electrode pointing straight down.


use just enough amperage by pressing on the foot pedal to barely melt and round the tip....you can easily see it get really hot quick on reverse polarity.

Dont make a ball like a tootsie roll , just use enough amperage to round the tip.

some welders like the way aluminum welds with a nicely rounded tip. There is something to be said for welding aluminum like this, but the problem is at low amperage on an edge, the arc wanders pretty bad.

Thats why I use a blunt taper, the arc is better at low amperage and then the tip balls naturally as needed as amperage increases.

When you weld aluminum, you monkey around with the tungsten a lot more than with steel because it is always getting crapped up or it changes shape due to always needing different amperage requirements.

good luck,

jody