10 Most Common Mistakes Made While Tig Welding Aluminum

While some may consider Tig welding to be a breeze, it requires a lot of focus and experience to weld aluminum. If you've had trouble doing so, here are the top 10 mistakes made while Tig welding aluminum.

1 - Newbies often forget to use the high frequency setting and set it to continuous. This ends up causing the machine to stall at low amperage since the alternating current loses most of its half cycles when the flow of the current is changed. If your machine sounds like a diesel engine, you need to adjust this setting when tig welding aluminum.

2 - Incorrect electrode size is another common mistake. Amateurs may forget how hot the electrode can get at 250amps on alterative current, so they go ahead and use the same electrode on direct current. This obviously causes the electrode to malfunction and blow up! Don't try to weld aluminum cans with a 1/8"" electrode because this will not work either.

3 - Newbies often use the wrong filler rod size. So they throw in a small filler rod which eventually makes it melt before any real welding is done. Conversely, a large filler rod can block the shielding gas and pulls the heat out of the puddle.

4 - Another Tig welding mistake to avoid like the plague is using a carbon steel brush to clean aluminum rather that a wire brush made of stainless steel. This is a basic guideline that no welder should ever forget.

5- New welders love to weld with a high torch angle. This leads to the filler metal melting and makes it in glob into the puddle. So, avoid torching at too much of an angle at all costs!

6 - Newbies, for the love of God, please don't use too long an arc when welding aluminum. You have the find the right spot where the arc is not too close nor too far. The last thing you want is to prep electrodes rather than tig weld aluminum.

7 - Following closely with number 6, you may also overload the argon on the torch. You may be confused by various resources telling you to pump up the torch gas, but if the arc is making too much noise to the point where you think your ear drums will pop, there is too much argon flow. As a frame of reference, you need only about 13-15 cfh for a 7/16"" tig cup. More does not always mean better.

8 - Don't follow every manual you see, especially when it comes to electrode stickout. Getting inadequate electrode stickout is another common problem. You will see Hobart training manuals recommend 1-1 1/2 electrode diameters, which is not enough. How can you be sure of your arc length if you can't see the tip of the electrode?


9 - Although it may be tempting, do not use pure tungsten because is not efficient. Get simple 2% lanthanated if you want a comprehensive electrode that works well on alternative current and direct current.

10 - Do not ball the electrode. Just make sure that it's round, but it shouldn't be overly circular. A big ball at the end of the electrode will decrease efficiency, and that's the last thing you want.