[falconluvr64]

Greetings all. I'm just starting to learn how to TIG. My need is to perform fillet welds on 3/32 6061 rectangular tubing. I've been having some trouble. I'm not a professional welder. I suppose I fit into the category of automotive enthusiast. I've performed gas and MIG processes in the past on steel. I'm not expecting the proverbial stack of dimes appearance. I just need fusion.

My machine is an Everlast 210. I started with 1/16 lanthanated tungsten and a number 5 cup. I set the gas flow between 10 and 15 cph. I am using alternating current, 120Hz, triangle waveform, 30% cleaning, ~5 seconds post flow, and 70 amps. Initially I performed straight beads on stock as I verified my machine settings. When I strike an arc I see the cleaning action breaking through the oxide layer - the frost - and a puddle forming.

I practiced striking the arc and running straight beads. Then I practiced adding filler. At first I had 3/32 4032, which I discovered was too thick for such thin material. I've since switched to 1/16 4032. Once I seemed to have reasonable repeatability I began attempts to join pieces. Whether I attempt a lap weld or fillet I run into trouble.

In the case of a lap weld it seems the arc favors the top piece. I've tried changing the torch angle to direct the arc. I also attempted to oscillate the arc between the upper and lower pieces, as I've done previously in gas welding. In either case it seems the top piece is taking all the heat. It starts to puddle and the edge melts/curls away before the bottom piece begins to puddle.

In the case of a fillet weld the problem is similar. The arc seems to favor one piece over the other. I'm unable to start a puddle which joins both pieces. The edges of the pieces I'm working with are not the most precise fit. The pieces are cut and then sanded. As an experiment I was able to achieve fusion when I stacked the pieces along factory edges, which had a more precise fit.

Thinking back to my gas welding experiences I though perhaps I needed a wider arc. I ordered varieties of 3/32 tungsten. Having received it I selected zirconated to start, as research seems to vary whether to use it or lanthanated. All other settings remained the same. I can't say the arc seemed wider. I did notice it seemed to build heat in the pieces much quicker, regardless of amperage settings. I definitely cooked them faster!

I'm not quite sure where to go next. I've attempted some adjustments to the machine settings - lower amperage, more cleaning, lower Hz. I've also run it in pulsed mode in an attempt to manage the heat. Typically 75/25 on/off with the lower cycle at 50% of max amperage. Even trying to perform a tack weld seems to fail miserably.

I've referred back to the numerous videos and tutorials available online. The bulk of them seems to show perfect tacks and beads regardless of the joint type. I don't think I've seen one yet which explains how to troubleshoot issues like mine. What I have noticed during my practice is that it seems best to rapidly apply current after striking the arc to form a puddle. Doing anything otherwise leads to cooking the piece and porosity.

Do you suggest any changes to my settings? Are there any other practice exercise that I should work on before a lap/fillet?

[VA-Sawyer]

You give a lot of details about your settings, but say very little about your preparation. "Cut and sanded", isn't good enough for Tig. You must remove the old oxide, grease and oils, dirt, etc. It needs to be "brite clean".
I'm also going to guess that your arc length is too long. As you get closer, there is a point where the sound changes. Any closer, and you will dip the tip. You want to be right at the point where the sound is about to change. That will help keep the arc where you want it. Good luck.

[Oscar]

and 70 amps.

↑ This is where I stopped reading. ↑

Set the machine to 210A and leave it there. A lot of videos don't emphasize this nearly enough, and it is responsible for 98% of all threads surrounding difficulty welding aluminum. If you can't wrap your head around that, you're gonna keep having a hard time.

Let's see a picture of your tungsten preparation.

[tweake]

My machine is an Everlast 210. I started with 1/16 lanthanated tungsten and a number 5 cup. I set the gas flow between 10 and 15 cph. I am using alternating current, 120Hz, triangle waveform, 30% cleaning, ~5 seconds post flow, and 70 amps.

this all screams low amps, which probably means your waiting a long long time to get a puddle going. you need to get puddle formed in a few seconds.
you need 3/32 tungsten, 2% lathenated is a good choice, a good alrounder that will handle the heat ok. your zirconated might hold up ok but expect issues at higher amps.
higher frequency requires more amps.
triangle wave (afaik) requires more amps.
with higher amps you will need more post flow.

the other trick is travel speed. to slow travel speed is what cooks your part.

i usually set the amps way more than i need. smash the pedal at the start to form the puddle, back off a bit and run. generally back off the pedal as the metal become to hot, especially as you come up to an edge so you don't blow the edge off. this is also where big tacks come in handy.

[tweake]

and 70 amps.

↑ This is where I stopped reading. ↑

Set the machine to 210A and leave it there. A lot of videos don't emphasize this nearly enough, and it is responsible for 98% of all threads surrounding difficulty welding aluminum. If you can't wrap your head around that, you're gonna keep having a hard time.

Let's see a picture of your tungsten preparation.

+1

most issues are due to low amps.

tungsten prep makes a LOT of difference.

[falconluvr64]

...You must remove the old oxide, grease and oils, dirt, etc. It needs to be brite clean...

I've prepared some of my attempts by wire brushing and wiping with a solvent. I haven't been doing it with all of them, as I figured learning the technique is where my time should be spent. For consistency I'll make sure I prepare all of them correctly.

...As you get closer, there is a point where the sound changes. Any closer, and you will dip the tip. You want to be right at the point where the sound is about to change...

I'll have to listen for that when I practice next. Thanks!

Set the machine to 210A and leave it there. A lot of videos don't emphasize this nearly enough, and it is responsible for 98% of all threads surrounding difficulty welding aluminum.

Interesting. I initially setup amperage based on the instruction manual for the given thickness and type of material. I think it was 90 at the maximum end. When I posted I had it down to 70 as I tried to avoid cooking the pieces. My initial runs were better the the later ones. I imagine it will take practice to learn the correct amperage control by foot pedal. I've been grinding my tungsten towards a 30 degree point, then blunting the fine point, then allowing it to ball naturally.

smash the pedal at the start to form the puddle, back off a bit and run. generally back off the pedal as the metal become to hot, especially as you come up to an edge so you don't blow the edge off

I did have better results when I rapidly formed the puddle. I'll have to set the amperage higher like you and Oscar suggest, and learn some foot pedal control. I'm using the factory one sent with the machine. I was thinking there must be a model out there which offers feedback to give the user some idea of the current, like a click at each 25% interval. We're obviously not able to look at the machine display during a weld. To a novice such as myself it would give me an idea of how much amperage I'm using.

My solenoid is flowing gas when I'm not actively welding. It seems to happen with these machines per research on Everlast forums. I've got a new one on order. I won't get back to practicing until it's installed. I'll let you all know how things turn out.

[tweake]

...You must remove the old oxide, grease and oils, dirt, etc. It needs to be brite clean...

I've prepared some of my attempts by wire brushing and wiping with a solvent. I haven't been doing it with all of them, as I figured learning the technique is where my time should be spent. For consistency I'll make sure I prepare all of them correctly.

clean them all.
not cleaning is a big mistake. been there done that. you do not want to be fighting other issues when learning.
besides welding is 90% prep work anyway so get into the habit.

smash the pedal at the start to form the puddle, back off a bit and run. generally back off the pedal as the metal become to hot, especially as you come up to an edge so you don't blow the edge off

I did have better results when I rapidly formed the puddle. I'll have to set the amperage higher like you and Oscar suggest, and learn some foot pedal control. I'm using the factory one sent with the machine. I was thinking there must be a model out there which offers feedback to give the user some idea of the current, like a click at each 25% interval. We're obviously not able to look at the machine display during a weld. To a novice such as myself it would give me an idea of how much amperage I'm using.
.

not heard of a pedal that has feedback, but i think the big thing your missing here is .......READ THE PUDDLE.
you don't need to know the amps.

[BillE.Dee]

get your amps up, frequency down some and set the machine to advanced wave (I believe the manual tells you the triangle wave is cool the puddle quicker, I can't get settled on that one) until you get your learning curve settled. short stick out and keep the tungsten close to the parent material and just peek under the cup where you're welding. It's going to be much like patting your head, rubbing your belly and working the gas pedal at the same time. YOU can do it !!! Make sure you're getting gas flow. Don't worry about adding filler til you get running nice beads. Don't be in a hurry Grasshopper and have fun.

[Burning Filler Rod]

falconluvr64,

I thank you for your post. I'm having the same issue with rectangle steel tubing. Large thanks to all that responded. I got a lot of good information from all of the comments.

Good luck 'falconluvr64'..... climbing this TIG learning curve is slippery! It's kinda like the golf game.... about the time you want to quit you make one nice shot and you are back in the game.

[5vzfehilux]

I'm still really not sure what the answer is with fillet and lap joints for aluminium for the less experienced & I've had my fair share of trouble with square tube fillets as well.

I think it's very common for newcomers to not have too much trouble learning to put stringers on flat plate and end up thinking that tigging aluminium is way easier than first thought, but then when we step it up a gear and have a go at 2F joints like laps and fillets everything fkn turns on its head! It seems that an AC arc just loves a flat surface to bounce off of, or an outside corner where the corner is pointing to the arc, but with fillets and lap joints where the root corner is pointing away from the arc, it's so much more of a struggle.

After months of home hobby fillet practice I have it to the point of getting a decent bead running but still have the problem of 'boomeranging' of the puddle (where the puddle wants to arc back behind the tungsten and the puddle edges on each leg of the fillet get ahead of the root, instead of how it should be where the puddle is more even across the front edge, maybe even slightly ahead of the leg puddles and down into the root). I can quickly fix this by jamming some rod in and that brings the root puddle up to level, but the correct way is to have the puddle flowing down into the root already and you just drop filler into that. It's also very easy for me to get the right puddle and root flow if I practice fillets on angle, which is of course pointless and for practice only, but even taking those practice skills and switching back to non - joined pieces, the same problems easily spring back up.

One thing I have found that I think has been mentioned already is welding alum is a real 'shock and awe' type of job. It needs to be initially hit with a lot of amps like it doesn't know what's hit it, to get things puddling quickly. If you go in underdone on the amperage side and decide to just sit there and wait, it will just not work and it gets heat soaked so easily and then everything from that point on just doesn't go. Another big no-no I found is being too 'trigger - happy' with the filler, ie trying to add it too early. That seems to stuff everything right up and it shouldn't even be thought of until the bases are wet and shiny, otherwise you end up with a big blob at the start of the weld that you then have to try and 'jump down off' to get even close to the root.

[5vzfehilux]

https://youtu.be/YoWSOC_Gx0w
From 18.45mins

[cj737]

In the case of a lap weld it seems the arc favors the top piece. I've tried changing the torch angle to direct the arc. I also attempted to oscillate the arc between the upper and lower pieces, as I've done previously in gas welding. In either case it seems the top piece is taking all the heat. It starts to puddle and the edge melts/curls away before the bottom piece begins to puddle.

In the case of a fillet weld the problem is similar

This is the meat of the matter. This is a symptom of arc distance, or even too short of a tungsten stick out length.

In a 45* orientation to the material, your torch and cup are now holding the tungsten farther away than with flat position welding. Extend the tungsten slightly so you can maintain a very tight arc in these positions. This will allow the heat you are running to get to the material.

A higher frequency focuses the arc, a lower frequency broadcasts the arc. I use 120 or > for laps, 60 - 90 for fillets, depending upon thickness of material. A slow onset of foot pedal enables the arc to begin wandering, and it may not stabilize until sufficient amps are active. One thing you can do, is to set the Pre-flow of gas to 1.0-2.0 seconds. If you are TIG welding with lows amps (anything under 100 in my book) having argon purge the immediate area helps arc initiation and stabilization. You won't use enough gas to make a dollar's difference over the course of a full bottle, but your welds/welding will improve.

[Poland308]

In the case of a lap weld it seems the arc favors the top piece. I've tried changing the torch angle to direct the arc. I also attempted to oscillate the arc between the upper and lower pieces, as I've done previously in gas welding. In either case it seems the top piece is taking all the heat. It starts to puddle and the edge melts/curls away before the bottom piece begins to puddle.

In the case of a fillet weld the problem is similar

This is the meat of the matter. This is a symptom of arc distance, or even too short of a tungsten stick out length.

In a 45* orientation to the material, your torch and cup are now holding the tungsten farther away than with flat position welding. Extend the tungsten slightly so you can maintain a very tight arc in these positions. This will allow the heat you are running to get to the material.

A higher frequency focuses the arc, a lower frequency broadcasts the arc. I use 120 or > for laps, 60 - 90 for fillets, depending upon thickness of material. A slow onset of foot pedal enables the arc to begin wandering, and it may not stabilize until sufficient amps are active. One thing you can do, is to set the Pre-flow of gas to 1.0-2.0 seconds. If you are TIG welding with lows amps (anything under 100 in my book) having argon purge the immediate area helps arc initiation and stabilization. You won't use enough gas to make a dollar's difference over the course of a full bottle, but your welds/welding will improve.

Stick out is very important. I change mine especially on v grove for pipe. I shorten it up as I fill out the joint. Inside corners are the same.

[5vzfehilux]

Extend the tungsten slightly

Stick out is very important. I change mine especially on v grove for pipe. I shorten it up as I fill out the joint

Would you mind measuring the stickout the next time, plus cup size? I normally set it about 5mm (1/5") for a #6 gas lens.

[Poland308]

If I’m down in the grove of a pipe weld, on a super coupon that’s like a 5/8 wall thickness. I start with a number 5 cup. Stick out is probably about 1/4 inch. I set it so if my cup is touching the side walls of the grove, and I’m holding it at 90 deg to the pipe axis. Then I lay a piece of filler wire in the bottom of the grove, usually 3/32. I set my stickout so that I’m almost touching the filler wire. This is set without the arc running (obviously). By almost touching I mean you might be able to slide a piece of paper between my tungsten tip and the top of the filler wire. Hard to say an exact measurement because the angle of a pipe joint and the angle of an inside corner aren’t quite the same. But the principle is. This seams to work out well for a pass or two. Then I step up a cup size or 2 as I work my way out. I rarely use over a 8 cup size.