Can your welding machine TIG weld Aluminum?

A considerable number of our clients ask about welding machine requirements in order to TIG weld aluminum.

TIG weld Aluminum with Direct Current Electrode Positive (DCEP) or DC(+)

*Can you *TIG weld aluminum without AC and a High Frequency box? **Yes, you can actually weld aluminum with a low cost DC power supply. It doesn’t make it any easier and you won’t be able to weld very thick materials, (typically 16 gauge maximum), but you can attain a high strength, great looking weld beads on Aluminum using the DC(+) technique.

TIG Weld Aluminum DC(+) procedure and technique:

To TIG weld aluminum, set your welding machine on DC+, (in some cases you just need to reverse the cables).

  • Place your 2% thoriated or ceriated tungsten sharpened (to a point) 1/8″ diameter – in your TIG torch
  • Set your 100% argon (not a mixture) flow at about 15-20 cfh
  • Scratch start and maintain a very close arc distance (maximum 1/16″ tungsten to puddle)
  • Be very patient as the heat builds up in your part.

When you TIG Weld Aluminum with DC(+), the following will occur:

After you scratch start and maintain an arc the point on the tungsten will start to ball and then sustain itself, you will then see Aluminum oxides starting to dissipate because you get half a cleaning cycle when you are TIG welding with DC+.

Your weld puddle will finally form and it is important to see the puddle and make small dabs of filler material to maintain control. Use 1/16″ diameter (maximum) filler material. If you contaminate the tungsten by touching the puddle, the then regrind your tungsten to a point.

    To TIG Weld aluminum is always a challenging task, but if you just have a small aluminum welding projects around the house, then this will work for you and the total set-up cost is less than $500.  It works well for material thickness of .020″-.062″.

If you are having trouble getting a puddle because your welding machine doesn’t have enough power, an easy and inexpensive technique to compensate is to “pre-heat with an electric paint stripper gun, place the blower gun over the area you would like to weld and leave it there for 5-10 minutes.  Its amazing how the preheat will help you when you  weld aluminum, and remember to always use filler material to avoid hot, short cracking.

Have fun with this.