[5vzfehilux]

Hi,

This isn't good enough for the 'what I welded today' thread so I posted here for tips on other things to try / think about for practice.

Piece is 1/8" (3mm) 6061 square tube about 14" long cut in 2 to give the two pieces to fillet weld.
Filler is 1/16" (1.6mm) 4043
Tungsten 3/32" (2.4mm) 2% lanth
140 amps on the foot pedal (yet to confirm accuracy of amps on the pedal)
Welded in the 2F position

Firstly admit to be being very lazy with the prep of everything. This was a piece that had been sitting out in the weather for a few months. The rust spots are actually rust from grinding steel near it and the sparks hit and cooled on it. The actual bit welded was just scrubbed with a stainless brush and nothing else.

Welded from right to left and as shown a disaster at the start with a touchdown and the black soot that always occurs. Just brushed the soot off. Reground the tungsten but too lazy to ball it first so let the weld ball it. Dumb idea as it developed a nodule on the tungsten part way thru but just kept going and it eventually balled nicely. The whole point of the exercise was to get practice with the puddle flowing in the root properly but I would say this only occurred for about half of the weld. Tightening the arc and pressing a bit harder on the pedal seemed to achieve that, plus timing the injection of filler at the right time. I also stopped twice on this weld to let things cool down.

Things I've noticed are the weld is a bit sunken, I think that is from not managing the heat plus undersize filler. So I will try larger filler. I also want to be able to weld this whole joint in one hit next time, so larger filler might help with the heat. The main thing though is getting the root to melt and flow properly to avoid the 'boomeranging'. I think that's just practice with arc length. Also preheating with a blowtorch might help next time so that less amps are required. It's also not a shiny weld which I'm guessing is from still being dirty and things getting a bit too hot. But any constructive feedback would be appreciated.

[Oscar]

You answered your own question. Prep is everything with aluminum. When things go south with aluminum, they really go south. It has little to no tolerance for laziness. Bead looks good otherwise.

[tweake]

Hi,

This isn't good enough for the 'what I welded today' thread so I posted here for tips on other things to try / think about for practice.

Piece is 1/8" (3mm) 6061 square tube about 14" long cut in 2 to give the two pieces to fillet weld.
Filler is 1/16" (1.6mm) 4043
Tungsten 3/32" (2.4mm) 2% lanth
140 amps on the foot pedal (yet to confirm accuracy of amps on the pedal)
Welded in the 2F position

140 amp is on the low side. i would set footpedal to 160. that will give you some good heat at the start and then you can back it off. that really helps flow it down into the root.

1/16 filler is on the small side but well done for even being able to get it in there without balling the end of it.
i would recommend 3/32 filler.

[5vzfehilux]

Cheers guys for your posts. I will give all your points a go.

[BugHunter]

Use a Scotch-Brite pad with soap and water and at least clean up your parts or you're wasting your time. Also, if you only have 16th inch filler you can always take two or three pieces with a cordless drill and spin them so they turn into one. Maybe hold the other end in a vice, then trim off the dirty ends.

[dunkster]

You can also try 409 cleaner...it has a mild etchant in it. Bottle says don't use on AL, but I use it to clean machined parts.

Now see what it's look like if you did that one little section the whole way....lol.
(I'm still trying to do that)

[5vzfehilux]

Also, if you only have 16th inch filler you can always take two or three pieces with a cordless drill and spin them so they turn into one

Far out, I never thought of that. I bought a little 400g pack of 3/32" filler ages ago but have never touched it because I had already bought heaps more 1/16" filler in a plastic tube and wanted to use that up first. But I thought I would give a bit of the thicker stuff a go last night and it's night and day difference between 1/16 and 3/32. The weld is full and sits up properly and obviously deals with the relatively high amps a lot better vs the 1/16 that gives the relatively small weld in the photo . I guess the only thing is spinning two 1/16s together means you skip 3/32 and go straight to 1/8"? But heaps keen to give it a go and see how it welds.

Another good thing I've just found with my cheapy welder is that the amp sticker on the foot pedal is actually pretty accurate, going off the digital readout of the welder itself. It's the cheap light grey pedal where your heel's on the ground and you press down with your toe, vs the proper one where your whole foot is on the pedal and you rock your foot forward.

Now see what it's look like if you did that one little section the whole way....lol.

you might have just blown up 99% of the welding posts on insta.