New Years Resolution: Learn To TIG Weld Aluminum
Bought a Everlast 250EX Inverter, with features like A/C freq adjust up to 250hz, balance, pulse from .2-500 ppm, start and stop arc from 0 to 200 amps.
Using 3/32 2% Lanthinated, 3/32 4043, Argon at 15, A/C 110-150hz, balance 33% EP, Start Amps 150-200, Run 130-150 amps, Preflow 5 sec, post 10.
Material is 5052 sheet, 3/16, 1/8, 3/32 cleaned with acetone and wire brushed (dedicated stainless)
She is a fickle mistress this process. One day I am laying her like a pro, and the next day she is retched, beads looking like a kindergarten art project.
Green stuff, what's that? I'm thinking maybe iron contaminate. I use a steel sheet metal welding table.
My arc likes to dance around like a voodoo priestess. I grind a roundish tip on my 2% Lanthinated.
Practice beads on a flat surface, not bad, but lap joints look like over-weld. I like petite welds, they're clean and look pro. Fillet welds, FORGET IT! All of Jody's videos omit the very start on this joint. The start would be very helpful to see what he does. Hale oh great one.
Why are some beads shiny and bright, while others are dull and frosty?
Argon flow??? How can you tell if the flow is set too high (low)?
Granted, I have only been at this a couple weeks, and I realize there is work involved. I'm not the most patient guy either, maybe that's part of my problem.
BDoubleU
- BDoubleU
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Nils - your machine settings sound appropriate. Here's a few answers and tips:
1. Green stuff: I have not seen this on aluminum before. But yes, it could come from contamination. It's recommended to keep steel-working tools away from aluminum. Use dedicated cleaning equipment - like a SS wire brush. Steel and other debris can contaminate the surface of the aluminum. Maybe someone else has seen this.
2. Arc dancing: AC welding current is, by nature, erratic. As you're increasing the amperage and establishing a weld pool, this should smooth out. It's easy to hesitate on aluminum - because it doesn't show a color change ... but I would advise ramping up to your weld current faster, forming a puddle & then allowing the puddle to melt the rod.
3. Fillet welds in a T-joint can be diffult. First, it's hard to see your puddle & tungsten. So, use enough stickout and position your body so you can see into the joint. Don't be afraid to stomp on the amperage - to quickly form a nice, round puddle. If you heat it up slowly, you will have problems.
4. Why are some welds shiny and some dull? Well, I'm guessing this is related to travel speed. If you weld faster & keep moving ahead, the arc will clean out in front of the puddle. As you slow down, the arc will actually etch the weld metal you have deposited. So, as you gain experience and get the hang of it, your welds will all appear shiny. Don't worry about that at this point ... it's not a major issue.
5. Overwelding: This is common with aluminum and it takes some time to learn how to control puddle width. Higher AC frequency settings will contstrict the arc, which helps a lot. But, you need to work on maintaining good puddle control throughout the weld by monitoring how wide the weld puddle is. As the aluminum heats up, you'll notice the puddle starts to widen out. The trick is - form a puddle quickly while the surrounding metal is still coming up to temp, then keep moving. Back off the amperge if you have to along the way ... but keep your puddle small. Like I mentioned above, if you heat the metal too slowly, the puddle can become too large to control ... if this happens, it's best to stop and allow the aluminum to cool down before you try again.
Here are some resources that may help ...
http://www.youtube.com/watch?v=oTZfDndP ... 2F86786975
http://www.youtube.com/watch?v=I73S7fBS ... 2F86786975
http://www.maxal.com/files/quicksiteima ... _chart.pdf
Keep working on it and let us know how it turns out. Good luck!
Brent
1. Green stuff: I have not seen this on aluminum before. But yes, it could come from contamination. It's recommended to keep steel-working tools away from aluminum. Use dedicated cleaning equipment - like a SS wire brush. Steel and other debris can contaminate the surface of the aluminum. Maybe someone else has seen this.
2. Arc dancing: AC welding current is, by nature, erratic. As you're increasing the amperage and establishing a weld pool, this should smooth out. It's easy to hesitate on aluminum - because it doesn't show a color change ... but I would advise ramping up to your weld current faster, forming a puddle & then allowing the puddle to melt the rod.
3. Fillet welds in a T-joint can be diffult. First, it's hard to see your puddle & tungsten. So, use enough stickout and position your body so you can see into the joint. Don't be afraid to stomp on the amperage - to quickly form a nice, round puddle. If you heat it up slowly, you will have problems.
4. Why are some welds shiny and some dull? Well, I'm guessing this is related to travel speed. If you weld faster & keep moving ahead, the arc will clean out in front of the puddle. As you slow down, the arc will actually etch the weld metal you have deposited. So, as you gain experience and get the hang of it, your welds will all appear shiny. Don't worry about that at this point ... it's not a major issue.
5. Overwelding: This is common with aluminum and it takes some time to learn how to control puddle width. Higher AC frequency settings will contstrict the arc, which helps a lot. But, you need to work on maintaining good puddle control throughout the weld by monitoring how wide the weld puddle is. As the aluminum heats up, you'll notice the puddle starts to widen out. The trick is - form a puddle quickly while the surrounding metal is still coming up to temp, then keep moving. Back off the amperge if you have to along the way ... but keep your puddle small. Like I mentioned above, if you heat the metal too slowly, the puddle can become too large to control ... if this happens, it's best to stop and allow the aluminum to cool down before you try again.
Here are some resources that may help ...
http://www.youtube.com/watch?v=oTZfDndP ... 2F86786975
http://www.youtube.com/watch?v=I73S7fBS ... 2F86786975
http://www.maxal.com/files/quicksiteima ... _chart.pdf
Keep working on it and let us know how it turns out. Good luck!
Brent
weldfusion.com
- Otto Nobedder
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I would add, in my experience the arc will wander less if you set your argon closer to 25 CFH, and this helps with those shiny welds in two ways... A more focused arc doesn't etch the surrounding area as much, and you have a bit more coverage.
I also prefer to keep the arc balance as far negative (penetrating) as the material will comfortably allow. On new clean metal, I'm often at 80%. This gives more heat in the metal for a given amperage, and more amps for a given size tungsten, and the "cleaning" effect of the positive cycle is less likely to affect the bead behind the puddle (helping with "shiny", too).
No two people do it exactly alike, so take all suggestions, including mine, with a grain of salt, and find what works for you.
Steve S
I also prefer to keep the arc balance as far negative (penetrating) as the material will comfortably allow. On new clean metal, I'm often at 80%. This gives more heat in the metal for a given amperage, and more amps for a given size tungsten, and the "cleaning" effect of the positive cycle is less likely to affect the bead behind the puddle (helping with "shiny", too).
No two people do it exactly alike, so take all suggestions, including mine, with a grain of salt, and find what works for you.
Steve S
BDoubleU
- BDoubleU
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Otto is right - make sure you have adequate gas covered & use more EN in the balance setting. If you see dark spots or pepper in the puddle, adjust your balance down accordingly.
weldfusion.com
ajlskater1
- ajlskater1
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Is it a green film on top of the weld?
As far as the arc wander, sharpen your tungsten to a sharp tip and put a small flat spot on the tip, also running a higher AC balance, turning up the frequency and running higher amps will help with that.
The shiny verse dull welds can be caused by a variety of things. Usually really cold weld will look really shiny and really hot welds will have a dull color. You AC balance can have this effect aswell if your travel speed is different, to slow you etch the weld. Also gas flow can cause this, usually welds done with to high of a gas flow will have a dull appearance.
How much gas to use depends a lot on the environment you are working in, cup size, and weld joint. Usually outside corner joints will take the most, something like 15 to 20 cfh with number 7 defuser, thick materials will take the upper range. Lap and butt welds you should be fine with 15 cfh. T joints take the least something like 10 to 15 cfh. You can tell if you gas is to high by the sound it will sound loud and erratic. If its to low the puddle will looking dirty and you will notice a lot less cleaning action around the weld. Those gas settings are for a shop environment with little to no air movement, if there is a lot of air movement you will have to up your gas flow.
T joints are hard to learn but since you have a inverter it will be easier to learn. Try running your AC balance at around 75 to 80, t joints do not require as much cleaning action because you weld area is concentrated. Also turning your frequency up to 200 will help focus the arc and try a number 4 cup. When I teach people to weld I always start them with a number just because it seems to be easier for people to learn with.
As far as the arc wander, sharpen your tungsten to a sharp tip and put a small flat spot on the tip, also running a higher AC balance, turning up the frequency and running higher amps will help with that.
The shiny verse dull welds can be caused by a variety of things. Usually really cold weld will look really shiny and really hot welds will have a dull color. You AC balance can have this effect aswell if your travel speed is different, to slow you etch the weld. Also gas flow can cause this, usually welds done with to high of a gas flow will have a dull appearance.
How much gas to use depends a lot on the environment you are working in, cup size, and weld joint. Usually outside corner joints will take the most, something like 15 to 20 cfh with number 7 defuser, thick materials will take the upper range. Lap and butt welds you should be fine with 15 cfh. T joints take the least something like 10 to 15 cfh. You can tell if you gas is to high by the sound it will sound loud and erratic. If its to low the puddle will looking dirty and you will notice a lot less cleaning action around the weld. Those gas settings are for a shop environment with little to no air movement, if there is a lot of air movement you will have to up your gas flow.
T joints are hard to learn but since you have a inverter it will be easier to learn. Try running your AC balance at around 75 to 80, t joints do not require as much cleaning action because you weld area is concentrated. Also turning your frequency up to 200 will help focus the arc and try a number 4 cup. When I teach people to weld I always start them with a number just because it seems to be easier for people to learn with.