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Stick welding aluminum

Just to be sure that different searches will end up here; this page is about stick welding aluminum, aluminum stick welding, how to stick weld aluminum, how to lay an aluminum stick weld, arc welding aluminum, aluminum arc welding, how to arc weld aluminum, how to lay an aluminum arc weld, SMAW welding aluminum, aluminum SMAW welding, how to SMAW weld aluminum, how to lay an aluminum SMAW weld, welding aluminum with a stick welder, welding aluminum with an arc welder, and welding aluminum with a SMAW welder.

The amount of misinformation on websites and various forums relating to this subject is astonishing. I aim to provide some decent information and proof that this works. I'm sure that everyone with a stick welder, arc welder, SMAW welder, or DC TIG welder has wanted to weld aluminum at one time or another. The main problem with this is actually information, not technology. Most web pages and forum posts state that a MIG or AC TIG welder with argon shielding gas is required to weld aluminum, which is not at all accurate. What should be stated is that AC TIG with argon, helium mix, or helium is the slowest, cleanest, and most controllable way to weld aluminum, which makes it especially good for welding thin aluminum. DC TIG can weld aluminum if helium mix or helium is used as the shielding gas, but its deep penetration is best for thicker welds. MIG, which is DC, is much faster than AC TIG or DC TIG, but it is not nearly as controllable because you cannot melt the base metal without adding filler metal. MIG was designed for fast buildup and continuous welding and it is still relatively clean because of the shielding gas. Neither TIG or MIG can weld aluminum in breezy conditions. However, stick welding aluminum is possible and actually works better than I expected.

Quick Summary Table

method polarity result quality
E4043 aluminum electrodes DCEP DCEP success good
E4043 aluminum electrodes AC AC failure
E4043 aluminum electrode and a single carbon arc electrode DC DC
E4043 aluminum electrode and twin carbon arc torch AC AC
zinc/tin aluminum brazing rods DCEP DCEP failure
zinc/tin aluminum brazing rods AC AC failure


E4043 aluminum electrodes DCEP - success

This experiment tries to DCEP stick weld aluminum with a flux-coated 1/8" electrode; the heat source is the arc between the consumable electrode and the base metal. I used 1/8" Harris 26 Aluminum Welding Electrodes that I purchased from Cyberweld.com. Hobart also makes aluminum electrodes. I saw them at Northern Tool, but I have not tried them yet. Lincoln Electric also has the Aluminweld 43 rods, but I have not tried those either. The Aluminweld 43 data sheet has useful instructions. The electrodes use different flux than more common steel electrodes, but the process is basically the same. The heat source is the arc between the consumable electrode and the base metal. All of the aluminum electrodes I have seen are 4043, so they can weld all of the same aluminum alloys that 4043 filler rod or wire can weld. They recommend DCEP/DCRP, which makes sense. AC TIG is able to remove the oxide layer on the base metal during the electrode positive portion of the alternating current. DCEP constantly removes the oxide layer from the base metal while the electrode flux keeps oxides from forming on the electrode metal and the molten pool. The flux protects the weld as it cools and forms a protective barrier, which works great even in windy conditions. They key is to move faster than you would with a steel electrode and not much weave movement is required since the aluminum flows better than steel. I welded a 3"x6"x60" aluminum box section out of 3"x0.125" angle for a storm grate extension and used less than 1 pound of electrodes. That works out to 60" x 4 seams = 240", which would have used quite a few TIG filler rods and a significant amount of argon from my 40cuft bottle. Some people have suggested that DCEN will work and give much better penetration on thicker base metal, but I have not had a chance to try it yet. These DC flux-coated electrodes will not work directly with an AC output welder because the molten flux seems to cool and freeze on the rod end during the zero voltage portion of the sine wave. The following photos show my newbie welding skills with these 1/8" electrodes at 120A. This bit of welding was done with a 160A inverter on a bottom side of the grate extension near the beginning of my learning curve. My welding and my welds got better as I progressed as shown in the photos.


So, my conclusion is that stick welding aluminum is great when a lot of structural (read not-perfectly-cosmetic) welding is needed. It should be possible to lay some beautiful welds and weld thinner metal this way, but my skills are not there yet. I was able to weld at near MIG speed without a MIG welder at or under equivalent consumable cost. The 1 pound of electrodes was about $25 shipped. One pound of aluminum welding wire is currently about $20 and my argon bottle costs about $15 to fill up.

Here are some relevant threads about stick welding aluminum over at Welding Web
http://weldingweb.com/showthread.php?t=58760&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=58440&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=11505&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=32628&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=32124&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=31070&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=11881&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=28989&highlight=stick+aluminum
http://weldingweb.com/showthread.php?t=28098&highlight=stick+aluminum

Here is an interesting video of someone else experimenting with aluminum electrodes. He would have had better results if he preheated the base metal and held the electrode closer to 90 degrees to the direction of travel.

E4043 aluminum electrodes AC - failure

This experiment tries to AC stick weld aluminum with a flux-coated 1/8" electrode; the heat source is the arc between the consumable electrode and the base metal. These DC-only flux-coated electrodes will not work directly with an AC output welder because the molten flux seems to cool and freeze on the rod end during the zero voltage portion of the sine wave, which prevents the arc from reigniting.

E4043 aluminum electrode and a single carbon arc electrode DC

This experiment tries to DC stick weld aluminum with a flux-coated 1/8" electrode and a single carbon arc electrode; the heat source is the arc between the carbon electrode and the base metal.

E4043 aluminum electrode and twin carbon arc torch AC

This experiment tries to AC stick weld aluminum with a flux-coated 1/8" electrode and twin carbon arc torch; the heat source is the arc between the two carbon electrodes.

zinc/tin aluminum brazing rods DCEP - failure

This experiment tries to DCEP stick braze aluminum with an 1/8" aluminum brazing rod as the electrode; the heat source is the arc between the consumable electrode and the base metal. This was a total failure. The bare brazing rod melted, splattered, smoked, and started burning on its own even at very low current. The metal in the brazing rod would need to be protected from the atmosphere for this to work.

zinc/tin aluminum brazing rods AC - failure

This experiment tries to AC stick braze aluminum with an 1/8" aluminum brazing rod as the electrode; the heat source is the arc between the consumable electrode and the base metal. This was a total failure with results nearly identical to trying bare brazing rod with DCEP.