[cosmokenney]

I'm trying to get some personal projects out of the way. Several of which involve some aluminum welding. I can get some decent welds on aluminum butt and lap joints. But man oh man do inside corner give me grief!!

I'm using a standard cup and collect without a gas lens. I can start a puddle and jam through no problem on butt and lap joints. My welds don't look too bad at all. Only problem I have is consistency in the width and spacing in the bead, but for my own projects I'm not concerned about looks. And I'm not overly coordinated so I'll never get "Instagram" weld beads anyway.

But for some reason those inside corners, what a mess. Basically if you watch Jody's video on aluminum inside corners where he shows what not to do to start a puddle, that's what I am seeing. It acts like too long of an arc and too much torch angle.

If by chance I luck out and get a small puddle started in the root of the joint I can usually pull off a decent weld using the move forward, stop, lengthen the arc and dab technique.

But usually, what I can is see a puddle form on either the vertical or horizontal piece -- or both. And let's say it forms on the vertical, if I move the electrode closer to the horizontal, the vertical one disappears. If I get impatient and try to use a little filler to get the puddle started, it either balls and drops a millimeter or two from the puddle. Or it will create a bridge with nothing but air in the root.

I swear if I get any closer to the root it'll foul my tungsten when I dab.

I've tried low and high frequency with little to no difference. I've increased my gas flow. I've tried different grinds on the tungsten. I haven't tried a gas lens but probably should. I've balled the tungsten, that's worse. I've tried changing torch position and so on.

This is all after doing several non-t-joint welds on the same material and getting decent results. So I'm pretty sure the settings are okay.

I'm starting to think I just need to set the welder to say 50% more amps than I would need on a flat joint. Then stomp on the pedal until the puddle starts to close in on the root. Back off and dab. Or dab and back off before moving forward?? Problem with that is I see a lot of blown out edges in my future This latest project was on some rectangular tube with .077 wall thickness. I had the welder set to 78 amps max on flat joints and used maybe 2/3s pedal amps for most of the welds.

Any ideas?

[Oscar]

This latest project was on some rectangular tube with .077 wall thickness. I had the welder set to 78 amps max on flat joints and used maybe 2/3s pedal amps for most of the welds.

Any ideas?

All you had to type was that last line, lol. You need WAY more amperage. It is the single most common theme among newbies who are trying to weld aluminum for the very first time. They are scared. Really, that's all it is, and practice of course. You need lots of amperage at the beginning to get the arc to really punch through straight into the joint, otherwise you just get a wandering arc and you get no where fast. Get some scrap. Set up an inside corner. Aim right at the center of the joint. No more than 1.5-2mm arc length. Set the amps to 150A. Mash the pedal INSTANTLY! Don't ramp up slowly like a scared little girl. Just stomp on it like you just got divorced and the judge said you don't have to give up anything to your ex-wife. Pedal to the metal. 0 to 100 as quickly as your leg muscle can twitch. It only takes 1 second of this arc and it will punch through. You might have to play with the amperage as all machines are slightly different, but yes, get used to using that much amperage at the beginning. Of course you need your balance and Frequency correct, but you didn't mention any of those so I can only assume you know what to set those too.

Remember, this scrap is for practice, which is what you need. You still need to learn to have filler rod ready, and to learn how to back off the pedal little by little as the heat is being wicked into the base material. The Mona Lisa wasn't painted in 15min. This will be quite the journey for you. Set money aside to replenish your argon. Gotta pay to play.

[cosmokenney]

This latest project was on some rectangular tube with .077 wall thickness. I had the welder set to 78 amps max on flat joints and used maybe 2/3s pedal amps for most of the welds.

Any ideas?

All you had to type was that last line, lol. You need WAY more amperage. It is the single most common theme among newbies who are trying to weld aluminum for the very first time. They are scared. Really, that's all it is, and practice of course. You need lots of amperage at the beginning to get the arc to really punch through straight into the joint, otherwise you just get a wandering arc and you get no where fast. Get some scrap. Set up an inside corner. Aim right at the center of the joint. No more than 1.5-2mm arc length. Set the amps to 150A. Mash the pedal INSTANTLY! Don't ramp up slowly like a scared little girl. Just stomp on it like you just got divorced and the judge said you don't have to give up anything to your ex-wife. Pedal to the metal. 0 to 100 as quickly as your leg muscle can twitch. It only takes 1 second of this arc and it will punch through. You might have to play with the amperage as all machines are slightly different, but yes, get used to using that much amperage at the beginning. Of course you need your balance and Frequency correct, but you didn't mention any of those so I can only assume you know what to set those too.

Remember, this scrap is for practice, which is what you need. You still need to learn to have filler rod ready, and to learn how to back off the pedal little by little as the heat is being wicked into the base material. The Mona Lisa wasn't painted in 15min. This will be quite the journey for you. Set money aside to replenish your argon. Gotta pay to play.

Okay I'll take off the skirt and try on the big boy pants! For the record I did try 85 amps without much difference. And yes I've welded enough aluminum to settle in on some basic settings for "perfect conditions".

I'm actually starting to lean towards lower frequency, like 60 hz, on aluminum. Seems to start the puddle really fast and I can move along pretty quickly during the weld.

[Oscar]

This latest project was on some rectangular tube with .077 wall thickness. I had the welder set to 78 amps max on flat joints and used maybe 2/3s pedal amps for most of the welds.

Any ideas?

All you had to type was that last line, lol. You need WAY more amperage. It is the single most common theme among newbies who are trying to weld aluminum for the very first time. They are scared. Really, that's all it is, and practice of course. You need lots of amperage at the beginning to get the arc to really punch through straight into the joint, otherwise you just get a wandering arc and you get no where fast. Get some scrap. Set up an inside corner. Aim right at the center of the joint. No more than 1.5-2mm arc length. Set the amps to 150A. Mash the pedal INSTANTLY! Don't ramp up slowly like a scared little girl. Just stomp on it like you just got divorced and the judge said you don't have to give up anything to your ex-wife. Pedal to the metal. 0 to 100 as quickly as your leg muscle can twitch. It only takes 1 second of this arc and it will punch through. You might have to play with the amperage as all machines are slightly different, but yes, get used to using that much amperage at the beginning. Of course you need your balance and Frequency correct, but you didn't mention any of those so I can only assume you know what to set those too.

Remember, this scrap is for practice, which is what you need. You still need to learn to have filler rod ready, and to learn how to back off the pedal little by little as the heat is being wicked into the base material. The Mona Lisa wasn't painted in 15min. This will be quite the journey for you. Set money aside to replenish your argon. Gotta pay to play.

Okay I'll take off the skirt and try on the big boy pants! For the record I did try 85 amps without much difference. And yes I've welded enough aluminum to settle in on some basic settings for "perfect conditions".

I'm actually starting to lean towards lower frequency, like 60 hz, on aluminum. Seems to start the puddle really fast and I can move along pretty quickly during the weld.

60Hz is fine, on flat/outside-corner/lap joints, but it exacerbates the problem of you being able to pin-point the arc in order to create a single puddle within an inside corner. A higher frequency will help you out right now, so you can get a better feel for things. Later when you get better, then play around with dropping the frequency down (because it makes things a bit more "difficult"), as you will be much more in-tune with what changes you need to make. If you have the ability to increase to 150-200Hz, try those you can see how they positively affect the ability to pin-point an AC arc. The frequency doesn't have to stay there, I'm merely suggesting it because it will get you along the right path right now in the beginning. Also, arc wander increases the more Electrode Positive (EP) balance you dial in; conversely it decreases with the more EN balance you dial in. More EN is better, to a certain point. Above 80% is difficult because then you get pepper floaties (soot floating within the puddle), but if you can run the balance up towards 80% EN (equivalently 20% EP, not sure how your machine handles this aspect), it too will help "straighten" out the arc. But it is of secondary importance relative to using the correct initial amperage.

[cj737]

Oscar and I differ in opinions on what Hz to use for inside corners. I like 60Hz because it produces a wider arc that heats both sides equally. A higher frequency does hit the root better, but only if you extend your tungsten and keep that tight arc in the root, which will get fouled the moment you punch in some filler.

Inside corners with ally are really tough. 100 Amps, yes, try 60Hz, a bit more stickout on your collet. I try to start higher than the bottom of the corner, get my puddle, then wash back down into the corner. I find that putting some heat into the part first, helps with flowing filler into the joint where it might be a 3-way inside fillet.

[Oscar]

Oscar and I differ in opinions on what Hz to use for inside corners. I like 60Hz because it produces a wider arc that heats both sides equally. A higher frequency does hit the root better, but only if you extend your tungsten and keep that tight arc in the root, which will get fouled the moment you punch in some filler.

Inside corners with ally are really tough. 100 Amps, yes, try 60Hz, a bit more stickout on your collet. I try to start higher than the bottom of the corner, get my puddle, then wash back down into the corner. I find that putting some heat into the part first, helps with flowing filler into the joint where it might be a 3-way inside fillet.

Yup, agree to disagree. I'm more of the get-to-both-sides-by-punching-into-the root, since the root always encompasses a little of both sides anyways. Still need a tight arc no matter what, IMO.

2:22 into the video.
zcURVxcHrGw

4:46 into the video
FuSNSp68l0U

[tweake]

Oscar and I differ in opinions on what Hz to use for inside corners. I like 60Hz because it produces a wider arc that heats both sides equally. A higher frequency does hit the root better, but only if you extend your tungsten and keep that tight arc in the root, which will get fouled the moment you punch in some filler.

Inside corners with ally are really tough. 100 Amps, yes, try 60Hz, a bit more stickout on your collet. I try to start higher than the bottom of the corner, get my puddle, then wash back down into the corner. I find that putting some heat into the part first, helps with flowing filler into the joint where it might be a 3-way inside fillet.

Yup, agree to disagree. I'm more of the get-to-both-sides-by-punching-into-the root, since the root always encompasses a little of both sides anyways. Still need a tight arc no matter what, IMO.

2:22 into the video.
zcURVxcHrGw

4:46 into the video
FuSNSp68l0U

thanks for that.
this is something i need to get into and experiment with the new machine.
my old machine is fixed frequency and often have to do the dap on the sides, bridge across, then blast it into the root routine.
unfortunately we are in lockdown and i cannot get gas. arghhhh.

[Oscar]

unfortunately we are in lockdown and i cannot get gas. arghhhh.

That bites! We are on lockdown, but hardware stores are still open. My LWS also sells hardware type stuff, so they are allowed to stay open.

[tweake]

unfortunately we are in lockdown and i cannot get gas. arghhhh.

That bites! We are on lockdown, but hardware stores are still open. My LWS also sells hardware type stuff, so they are allowed to stay open.

ours are only open for essential services only and are only open to commercial account holders, which i'm not.

[Spartan]

unfortunately we are in lockdown and i cannot get gas. arghhhh.

That bites! We are on lockdown, but hardware stores are still open. My LWS also sells hardware type stuff, so they are allowed to stay open.

ours are only open for essential services only and are only open to commercial account holders, which i'm not.

My suppliers are shutdown. The morning that I heard we were about to get shut down I went out and rented another full bottle of argon. Glad I did. Got lucky!

[TraditionalToolworks]

I don't know if my LWS is open or not, I just assumed that they were as I figured they were essential business supplying welding gas. Praxire didn't say they were closed on their website, but good thing I ordered some aluminum tig filler on Amazon tonight, coming from jegs. Should be here by the end of the week, or early next week. I have at least 3/4 of a 125 cu ft tank.

No, looks like they're open, Praxair is owned by Linde.

https://www.linde.com/customers/covid-19-statement

[BillE.Dee]

my gas supplier is open...he said "I supply the townships and local towns with gas incase they have a breakdown of sewer and water supplies, that makes me essential." He also provides medical portable oxygen. I also just found out I can get metal from the valley.... so far.

[cosmokenney]

Also, arc wander increases the more Electrode Positive (EP) balance you dial in; conversely it decreases with the more EN balance you dial in. More EN is better, to a certain point. Above 80% is difficult because then you get pepper floaties (soot floating within the puddle), but if you can run the balance up towards 80% EN (equivalently 20% EP, not sure how your machine handles this aspect), it too will help "straighten" out the arc.

I didn't know that. Great knowledge here! I've been running at 30% EP and always wondering why the ARC wanders. With my jittery hands that makes the arc jump around a lot on inside corners. Shake a little one way and it jumps to the vertical, shake a little to the other direction and boom its now on the horizontal.

[Oscar]

Also, arc wander increases the more Electrode Positive (EP) balance you dial in; conversely it decreases with the more EN balance you dial in. More EN is better, to a certain point. Above 80% is difficult because then you get pepper floaties (soot floating within the puddle), but if you can run the balance up towards 80% EN (equivalently 20% EP, not sure how your machine handles this aspect), it too will help "straighten" out the arc.

I didn't know that. Great knowledge here! I've been running at 30% EP and always wondering why the ARC wanders. With my jittery hands that makes the arc jump around a lot on inside corners. Shake a little one way and it jumps to the vertical, shake a little to the other direction and boom its now on the horizontal.

Do keep in mind, the difference is not "mind blowing" unless you do a 30-50% swing in balance. But IMO, it's there enough to notice it. Perhaps 5% won't make a different but 10%+ does IMO.

[Arno]

Alu inside corners are often tricky for many people.

Here Jody's mantra of 'keep a tight arc' and giving it enough amps really helps to get the job done. Bury that tungsten deep in the corner and hit that pedal.

Difficulty here lies mostly in getting going smoothly. The initial puddle forming takes longer on a cold workpiece and as you keep a very tight arc it's often tricky to get that first 'dab' in there to link the sides without immediately stabbing or dunking the tungsten in the resulting 'bridge'.

I do find that once you do have the 'start' going it then keeping it moving is less of an issue. With the caveat that the puddle raises up a lot more than on steel so it will still catch you out ever so often until you get more experience.. And even then you see someone like 6061.com who does loads of this stuff for a living still sometimes dunk his tungsten in some conditions (and I like how he does show that! with a counter in some cases )

Still.. The torch angle(s) can be important as the tungsten is already running way hotter than on DC and get the angle 'just wrong' and the corner will focus/reflect a lot of the heat back at it and can (in my experience) cause sudden and unexplained tip melting/balling with then a resulting arc wander after that.

Bye, Arno.

[5vzfehilux]

Alu inside corners are often tricky for many people.

Yep sure are. IC's & fillets can leave you scratching your head and then cracking the shits because youve usually just done some flat stringers without too much trouble & they came out looking pretty good and then you have a stab at corners and it all turns to shite.
When I do these joints I just remind myself that the shape of the AC arc cone seems to just not lend itself well to inside corner joints. It seems to be more fanned out and flat or maybe concave on the bottom than DC, particularly with a cheaper machine like mine where you can dial in any frequency you want so long as it's 60Hz, meaning that the arc is all too happy to bite into the toes of the corner weld before it wants to think about the root. But as has been said, the root is the most important part to hit. If I try my machine on outside corner edges it's a cakewalk though. The "root" in this case is instead closest to the arc and that seems to work way better with an AC cone.
Arno's post and all the info here is good and it's now just practice time. Even if you just forget about running the weld and focus on creating the bridge for now, that might help.
And there is definitely a trap of adding filler too early and too much of it as well. Adding too early will reduce the puddle heat just when you need the opposite to get things started, and if the puddle isn't hot enough or there even is no puddle yet, the arc will just melt your filler rod and burn it back instead. Too much filler at the start also means you will end up with a big blob that even if you manage to miss hitting the tungsten with when you try and move the weld forward, you then have to try and jump down off the back of it to get back to close to the root to run the weld over the rest of the joint.

[Oscar]

Alu inside corners are often tricky for many people.

Yep sure are. IC's & fillets can leave you scratching your head and then cracking the shits because youve usually just done some flat stringers without too much trouble & they came out looking pretty good and then you have a stab at corners and it all turns to shite.
When I do these joints I just remind myself that the shape of the AC arc cone seems to just not lend itself well to inside corner joints. It seems to be more fanned out and flat or maybe concave on the bottom than DC, particularly with a cheaper machine like mine where you can dial in any frequency you want so long as it's 60Hz, meaning that the arc is all too happy to bite into the toes of the corner weld before it wants to think about the root. But as has been said, the root is the most important part to hit. If I try my machine on outside corner edges it's a cakewalk though. The "root" in this case is instead closest to the arc and that seems to work way better with an AC cone.
Arno's post and all the info here is good and it's now just practice time. Even if you just forget about running the weld and focus on creating the bridge for now, that might help.
And there is definitely a trap of adding filler too early and too much of it as well. Adding too early will reduce the puddle heat just when you need the opposite to get things started, and if the puddle isn't hot enough or there even is no puddle yet, the arc will just melt your filler rod and burn it back instead. Too much filler at the start also means you will end up with a big blob that even if you manage to miss hitting the tungsten with when you try and move the weld forward, you then have to try and jump down off the back of it to get back to close to the root to run the weld over the rest of the joint.

Very good synopsis, especially the part that I bold-faced and underlined. Anytime you have an inside fillet (<180°), the sides of the joint are always closer to the side of the tungsten than the root is to the tip. The smaller the included angle, the closer the sides are, so the worse the arc wants to wander and fan out, especially when the AC frequency is low. It's a reason why so many have trouble with aluminum T-joints and why we see posts about that about once a week. But that's ok, we're here to help.

[Spartan]

In this situation, I've also found it helpful to step down a size in both tungsten and filler rod to do a narrow "root pass" first. I know it's often a goal for folks to have a one-size-fits-all tungsten, but going down a size in tungsten, when needed, will really help to give you a smaller arc cone and to pin-point the heat right into the root area where it is needed. Easy on steels, but can obviously be a bit tricky on thicker AL with the higher amperages needed so you may quickly reach a limit on how small of a tungsten you can go to.

Having a wider grind angle (about 75-90 deg. included angle) also seems to narrow the arc and help pin-point the heat down into the root of the filet when welding AL. Seems counter-intuitive compared to the sharp angle grinds, but it works well for me.

[BugHunter]

When you're doing an inside corner there is a fair amount of prep involved. Don't be afraid to get your wire brush out, a clean one for that matter, and break up the oxide layer on that material you are trying to lay the fillet in. Another problem is when you are doing really fine aluminum, let's say 16 gauge or smaller. You really should almost have the parts in a fixture so that you can get a really good ground. I think it's pretty common if you are practicing to just lay Parts on the table and think that your ground is okay. If you are wondering why the current is jumping all over hell, it's because it doesn't have a really clear path to go home. When you watch these guys who do really nice inside Corners it's probably because they've got a great set-up that not only holds apart super steady but also gives them good continuity to ground. There is more to that then you would think.

[BugHunter]

I will also say this. It happens that today I was doing some inside corners on aluminum myself. Don't underestimate the filler you are using. I typically use off-the-shelf 4043 filler rod. When things are important, I use Neptune from Rockmount. Before you search, sit down because you're going to get some sticker shock. But let me tell you if you want to do a nice inside corner they have the filler material that will flow like you've never worked before. No this is not a commercial and I do not get a commission.

[cosmokenney]

I will also say this. It happens that today I was doing some inside corners on aluminum myself. Don't underestimate the filler you are using. I typically use off-the-shelf 4043 filler rod. When things are important, I use Neptune from Rockmount. Before you search, sit down because you're going to get some sticker shock. But let me tell you if you want to do a nice inside corner they have the filler material that will flow like you've never worked before. No this is not a commercial and I do not get a commission.

Thanks for the input. For most projects I'm not really looking for high end aesthetics. I just want a good strong weld. I can do that in most cases but the inside corners are just nuts. I still haven't gotten into the garage to try out the suggestion from this thread, but I will report back when I do.

[BugHunter]

Got a break here at work and I just ran a test on this for this thread.

.058" Alum 3003 (soft stuff for cold-work forming).
Quoins let's call them 4" x 1-1/4" Shear cut.
Parts cleaned (especially the edges) using hot water and Boraxo hand soap. I have Dynaflux Aluminum Cleaner, I tried a set with that too, but honestly, it sucks. You'll grow a third arm using the stuff and I get sick of the gloves in the trash after each use. It'll eat a cloth rag... And IMO it doesn't work any better than soap and water. So wash the parts and rinse them well, then dry.

Tried 1/16" tungsten, 60-80 amps, #8 Furic Cup so gas lens of course, no pulse, and using big blocks of aluminum (3" x 2" x 6" machined square) as a fixture. I didn't like that at all. If I could add more amps on slightly thicker material, ok. But as it was, it was just too cold for that torch setup. At 80 amps the tungsten was fully glowing red, which means 80 amps is not getting to the part. (resistance increases with temp).

Switched to 3/32" tungsten, same Furic cup and 80 amps. Didn't like that either really.

Clamped up the parts to make an outside corner on one of the alum blocks. Set to 125 amps, and put 3 burst tacks on. Turned the part over and used a previously used part as a support with a finger-hold-weight to hold the part securely for the inside corner. Ran that without fixturing at 125 amps, never ran near full pedal (but it was available), but did make a few bursts of higher amps. That worked pretty well.

FYI, Balance was set to 80% for all that. I was trying to get more power into the part and less in the tungsten, and that part worked. The part really didn't seem to need much cleaning action. The un-brushed part I tried worked as good or better than the one I did with a brand new brush.

I'll try to post up a couple pics of it later.

[BugHunter]

Ok, I did yet another one. Put 3 tacks on the outside corner to begin, then flipped it over and set it on the table with just a piece to help support it at an angle and a weight for stability.

Equipment as I finished with above. FYI, I was running 180hz / 80% in the examples above, but here set to 200hz 70%. I would say I like this better, and with the heavier tungsten, might try 65% or even 60. It also might help some if I file the rough shear-cut edges some and eliminate the areas where dirt could hide from my soap/water.

Still at 125 and light pedal. The pics show I was a little too hot, so less amps are in order.

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[TraditionalToolworks]

If that is 1/8" you might try leaving the amps the same and using a large size filler. Inside corner takes some heat, but you need to use a fair amount of filler so it's doesn't keyhole on 'ya. If it is 1/8" material you should have the pedal floored on the inside corner. (do as I say, not as I do... )

Are you using 1/16" filler?

In the beginning it doesn't look too bad, but possibly not enough filler as you didn't get the stacked dime effect.

[BugHunter]

Here's two more. The first at 110A and the next at 90A. Parts are now smaller because I cut the old welds off in the shear and welded them again. Shown below. The one with the welding weight in the pic is the 110A one. Still 70% balance,

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I tried to replicate the troubles you mentioned in the first post, and after some playing with it myself, I think probably the biggest issue you have is torch angle. When I do these, I find it near impossible to work without the torch at 90 deg aiming dead straight into the root or maybe even a few degrees toward the direction of travel. If you lean even the slightest bit away from the travel (so you can see), you tend to melt the filler before you dab. Then of course it's a disaster. You need a really really tight arc, which I realize is tough to do when you can't see (cup in the way). This furic cup really helps with that. I bet I'm holding less than 1/16" arc. I actually go sorta slow when I think about it. Real deliberate, and very careful to only dab just barely to the leading edge of the puddle. Be careful with the heat not to burn through. Let the rod flow in when it barely touches the puddle, do not stuff it in there (if that makes sense).

Lastly, here's one that I ran with the Neptune filler I mentioned earlier. You can still see I was too hot on the right side. That's with my weight in the way... No excuse. Then I moved the weight out of the way and went a little faster, the weld fillet looks much nicer. I was going right to left. Also, I put the scraps I cut off in the shear to show how little of the piece I throw away to weld them again. Makes for more practice with less pieces.

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