[ManSkirtBrew]

Hobbyist welder here. Been doing stainless/carbon steel for a while, moving into aluminum.

Having some trouble on outside and inside corner welds, getting the puddles from the two parts to come together as one. Especially when trying to do an autogenous tack, but also when using filler.

Like this mess here, for example. I could not for the life of me get the two sides of that weld to come together.

20210311_165103.jpg (61.74 KiB) Viewed 5308 times

But sometimes I have no problem at all and can make nice tacks on outside corners like this:

20210311_165112.jpg (51.17 KiB) Viewed 5308 times

Which is almost as frustrating, because I'm not sure what I did differently to make it work so easily.

Once I get things started, I can run a reasonably nice weld (I mean, ignoring the tip dip and getting too hot at the end--at least I know how to fix those things )

20210311_165150.jpg (15.43 KiB) Viewed 5308 times

TIA for any suggestions. I've tried searching here and on YouTube, but I haven't come up with the right combination of search terms.

Setup:

1/8" Al, wire brushed and acetone.

2018 AHP AlphaTIG 200

#5 standard cup. 3/32 2% lanthanated tungsten. 125amps. 120hz. 35% balance. Foot pedal. 12-13 CFH argon.

[Louie1961]

I would crank your amps up a bit more (130-140), hit the pedal hard to start your puddle, and then back off the amps with the foot pedal as needed. What your describing is pretty common issue with aluminum. The way I was taught was hit it with a lot of amps to start, make sure a puddle forms on both sides. If not redirect the heat and actually make two puddles if you have to, then stab the filler in from the side to bridge the two puddles. I am sure this is one of many ways to skin the cat, but it was the I learned. They guys over at Weldingweb used to run an in person TIG clinic, and I was invited to attend some number of years (decades?) ago. Met some awesome welders who do amazing stuff with really old, refrigerator sized, antique welders.

[G-ManBart]

Setup:

1/8" Al, wire brushed and acetone.

2018 AHP AlphaTIG 200

#5 standard cup. 3/32 2% lanthanated tungsten. 125amps. 120hz. 35% balance. Foot pedal. 12-13 CFH argon.

For a fillet weld like that, you're probably right on the edge as Louie suggested. No two machines are the same, and they will vary with input power slightly as well...so even comparing settings isn't exact. Just dropping the balance to 30% cleaning might be enough to help get the puddle started, but higher amps is just as easy of a fix.

This follows along with another thread where I just posted a link to a video that's worth watching. They set up a couple of pieces of 1/8" and used 125A, 120Hz and 30% cleaning and used both 1/16 and 3/32 filler (varying with the position of the weld). I think it's a really fun drill and I've done a bunch of them since I saw the video. There are times when I don't have a welding project ready, but want to spend a few minutes under the hood to keep from getting rusty....I'll knock out one or two of these and then pad beads on the remaining clean surfaces. Sometimes I'll start two and alternate back and forth so they don't get quite as hot. That doesn't matter at first, but after a while you can do them pretty fast after you have the steps down.

https://www.youtube.com/watch?v=YoWSOC_Gx0w
I think it's a fun drill and have done many of them when testing a machine

[Oscar]

More amps. The corner in the 2nd pic takes less amps than the outside corner edges in the 2nd pic which is why you probably had more success with it. More amps, don't baby the pedal. React fast and dip the filler in as soon as the puddle is ready to accept it. Not easy, takes practice. That's how I taught myself after way too many curled edges.

[tweake]

I would crank your amps up a bit more (130-140), hit the pedal hard to start your puddle, and then back off the amps with the foot pedal as needed. What your describing is pretty common issue with aluminum. The way I was taught was hit it with a lot of amps to start, make sure a puddle forms on both sides. If not redirect the heat and actually make two puddles if you have to, then stab the filler in from the side to bridge the two puddles. I am sure this is one of many ways to skin the cat, but it was the I learned.........

+1
tho if you have a large gap then it pays to dab and build up the bottom side first. then melt, dab and flow the top down to the bottom. once its bridges then hit it with big amps to sink it in and push the puddle along. back it off and weld as normal.

['Stang]

A lot of good advice in these replies. I do mostly aluminum and love it. The first thing I would do in your place is lower the frequency to 100. I find that helps on outside corners.

[walz10]

I agree with the responses above suggesting more amps. The only thing that hasn’t been addressed is your fusion tacks. Your going to need a bunch more amps for those. Like double what you would weld with. Or in your case turn the machine all the way up and get on the pedal full and right back off of it. I had all the same problems as you when beginning to TIG weld. You’re really close to getting everything just right from the looks of things. Just up your amps on everything a little and practice practice practice. Don’t be afraid to try different things, sure some of it isn’t going to work but you’ll learn from it. Another thing that took me a minute to figure out is why when I welded on a coupon for a while things changed. Well, yeah the temperature of the metal makes a difference. Hope this helps someone


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[BugHunter]

I mostly agree with everything above...

I like your 35%, but I might even try 40. Might also try 60hz.

I'd also sharpen the tungsten a little more and get it in tighter. Maybe touch off the part, back off EVER so slightly, and then hit the pedal and start the arc. In close is gonna work way better than trying to long arc, which might not be the correct term for what you're doing, but I'd say your arc is too long. Getting in so close does take some practice.

You might also set the tungsten up with the cup touching the part, get the distance perfect with the cup touching, then leave it there and strike the arc. Now keep in mind, in the real world of aluminum welding, there's applications where the cup touching the part is a serious no-no. Like, failed inspection no-no. That's not going to apply to you here, but after you get the hang of this better, get away from touching the part. try using it as a crutch for now, then slowly eliminate it.

Might also take a good look at your ground clamp. Is it a good quality clamp, and are you getting a good ground? If it's a chintsy clamp, maybe lock it down with a welding clamp or vise grips so it makes better contact. Same goes for your parts. They need good conductivity to the work lead. Otherwise, the arc will tend to wander. Makes inside corners especially difficult.

[ManSkirtBrew]

Thanks for all the great replies!

I had been having a lot of trouble with blowing through the parts at higher amps when trying to tack, so I assumed I was applying too much heat, which is how I ended up back at 125.

I'm guessing that I'm just not experienced enough to keep up with how fast things are happening. Just knowing what to practice is super helpful.

I'd also sharpen the tungsten a little more and get it in tighter. Maybe touch off the part, back off EVER so slightly, and then hit the pedal and start the arc.

Now that you mention it, the successful autogenous tack I showed was when I got the tungsten down as deep in the valley of the two pieces that I could. I'll keep it in mind, as well as the ground for the parts.

[Spartan]

FWIW, I avoid fusion tacks on AL at all costs. Really only use it as a last resort when there is no way to properly hold/clamp the pieces together and I need to hold them with one hand...and even then I will still attempt to feed rod with that same hand sometimes if practical. The fusion tacks on AL have a high risk of curling away the material as you were seeing, and even when it does work out ok, those same tacks now have a high risk of cracking. Just not worth it, IMO.

Now for people who consistently have kick ass, zero-gap fit-ups and perfectly prepped material...sure those fusion tacks may work out ok.

[wahiiii]

Grear replies here! I often experiement with different wires and material and the results come out like this.

[ManSkirtBrew]

FWIW, I avoid fusion tacks on AL at all costs.

I'm learning this. But I was having the same problem even adding filler--both sides of the joint would build up and I'd end up with the same disaster I started with...just much bigger.

So I figure if I learn the right way to do it first, I'll be better off in the long run.

[ManSkirtBrew]

Thank you so much for the advice. I cranked the amps to 200, concentrated on a tight arc, and the results were absolutely night-and-day. These are without filler:

Tacks

20210328_160510.jpg (23.15 KiB) Viewed 4963 times

At 140A, I was able to run a pretty nice bead. Still have to work on my lead in/out, but this is huge progress.

Bead

image-20210328_161459.jpg (18.11 KiB) Viewed 4963 times

Got bold and did some tacking on the soccer ball. I don't have a good way to clamp the pieces in place, so being able to hold them and snap on a quick tack or two is a huge help.

Soccer

20210328_165006.jpg (59.65 KiB) Viewed 4963 times

I do have a new question, though. This is what the inside of that corner weld looks like:

Inside of corner

image-20210328_161642.jpg (14.77 KiB) Viewed 4963 times

Is this normal, or is there something I should be doing differently?

[Oscar]

That is normal, as far as the look. It will not look like the welded part due to the oxide layer still being present on that underside, and remaining as a "skin layer" underneath the molten aluminum.

[Louie1961]

You might not need that much penetration through the backside. I don't think it hurts anything, but its just not required. You can also see that you heat is inconsistent as your push through is greater in some spots vs others. You could work on your consistency.

A lot of people believe you must have 100% penetration on every weld, but that just isn't the case. https://www.lincolnelectric.com/en-us/s ... ation.aspx

[G-ManBart]

Lots of progress there!

I'm certainly no expert, but something I've noticed with aluminum is that it's even more important to get into a truly comfortable, supported position so you can move the torch at a consistent speed. As Louie mentioned, there's some inconsistency in the heat, and that's often due to travel speed. A good drill is to make a box out of aluminum that will become a prop for your torch hand for later projects....the more sizes, the better. The other thing that goes along with consistent travel speed is simply getting faster and consistent at feeding filler so your torch hand isn't waiting for the filler.

It's all just a bit of technique and practice, but you've already made a huge improvement!

[cj737]

That “inside corner weld” shows a significant exposure to heat meaning you are running too low of amperage. The internal material is melting before the oxide layer. I’d love to see the front side of that weld. But I think you need to crank up the amps.

The reason I say too low, is the backside penetration is bulged from the middle only, not convex to the edges. Symptom of overheating or wicked slow travel speed with too low of heat. Once you get aluminum hot and wetted, start stuffing filler and moving along. You won’t see that much backside penetration but ample heat signature.

[ManSkirtBrew]

That “inside corner weld” shows a significant exposure to heat meaning you are running too low of amperage. The internal material is melting before the oxide layer. I’d love to see the front side of that weld. But I think you need to crank up the amps.

It's two pictures above in the same post. This should be the link to it.

Once you get aluminum hot and wetted, start stuffing filler and moving along. You won’t see that much backside penetration but ample heat signature.

Looking at my welds vs. others, it does look like I'm not traveling far enough before adding filler, nor adding enough filler. I think I'm still using the same muscle memory I've developed with stainless welding.

I've been noticing the Al puddle not traveling ahead of the arc as fast as I'd like, which would definitely agree with the more amps and move faster suggestions.

Thanks again for everyone's help! It's much appreciated. I'll keep at it. Pitter patter.

[cj737]

That “inside corner weld” shows a significant exposure to heat meaning you are running too low of amperage. The internal material is melting before the oxide layer. I’d love to see the front side of that weld. But I think you need to crank up the amps.

It's two pictures above in the same post. This should be the link to it.

Once you get aluminum hot and wetted, start stuffing filler and moving along. You won’t see that much backside penetration but ample heat signature.

Looking at my welds vs. others, it does look like I'm not traveling far enough before adding filler, nor adding enough filler. I think I'm still using the same muscle memory I've developed with stainless welding.

I've been noticing the Al puddle not traveling ahead of the arc as fast as I'd like, which would definitely agree with the more amps and move faster suggestions.

Thanks again for everyone's help! It's much appreciated. I'll keep at it. Pitter patter.

Yes, the outside shows less filler than some others use, but honestly, it looks perfectly strong. The only aspect that catches my eye on the outside is the edges are slightly "undercut" which indicates "under-filled". So yes, probably can stuff a bit more filler in there.

Aluminum is a very sluggish puddle compared to stainless. You need to really cram a lot of filler in to "move it" forward so there's an excess of weld pool. Ti is even worse in it's sluggishness. That's often why the ripples in Ti welds are so tight together- you can't push the puddle for crap.

Your welds look really, really good for someone so new. Head up, keep cranking, and you'll continually improve! Not a thing you shouldn't be proud of already.

[BugHunter]

I failed to mention one item that seems a little counterintuitive, but I often see people miss when having this trouble with aluminum.... Should have mentioned this before. Even in videos, I don't think I ever heard anyone mention the reasoning for this.

After sharpening the tungsten to a point, it still is important to ball the tip of it. Yes, you "can" get away with it pointed some times. And after a little arc time, it will ball itself some. But scratches on a tungsten are the bane of a nice arc. Scratches are the very thing that helps the arc to find new places to jump from, hence, arc wander. Now, you 'can' polish the tungsten real well, but it'll never get as perfect as it will if you melt the end and it re-forms as a solid mass. NOW you have a perfectly polished electrode from which the arc will always jump to the closest member (precisely what you want). It no longer has 100 choices of scratched sharp edges to choose from.

So, light up some, even if only to stick a tiny little ball on the end of a very sharp point. But, make sure you give the arc no choice as to where it's supposed to be. Nicely polished sides where the ball isn't, won't hurt either.

[tweake]

I failed to mention one item that seems a little counterintuitive, but I often see people miss when having this trouble with aluminum.... Should have mentioned this before. Even in videos, I don't think I ever heard anyone mention the reasoning for this.

After sharpening the tungsten to a point, it still is important to ball the tip of it. Yes, you "can" get away with it pointed some times. And after a little arc time, it will ball itself some. But scratches on a tungsten are the bane of a nice arc. Scratches are the very thing that helps the arc to find new places to jump from, hence, arc wander. Now, you 'can' polish the tungsten real well, but it'll never get as perfect as it will if you melt the end and it re-forms as a solid mass. NOW you have a perfectly polished electrode from which the arc will always jump to the closest member (precisely what you want). It no longer has 100 choices of scratched sharp edges to choose from.

So, light up some, even if only to stick a tiny little ball on the end of a very sharp point. But, make sure you give the arc no choice as to where it's supposed to be. Nicely polished sides where the ball isn't, won't hurt either.

also the advantage of doing that is you reduce the risk of tungsten getting into your puddle. big amps and fine tips don't play nicely, and you can blow the tip right off.
this is why i prefer to nip the tip off ie truncate it. that ways its fairly similar to what it will be like when welding.

notice jody takes a different view. he uses a sharp point for tacking which can help do pin point tacks. i suspect buy the time you have done quite a few tacks its starting to round the tip off.