Learning to MIG Aluminum

[morpwr]

I am trying to weld .09 thick 5052 aluminum tubes. They vary from 15", up to 30" in diameter. The tubes are five feet long. I made up a linear welder, using a CAT 1 welding carriage, to take the MIG gun along. I am currently using a 350P with aluma pro push pull gun. There is 5356 .047 wire in the welder and argon for gas. The linear carriage has a maximum speed of 36"/minute. So far I am using a 1/2" nozzle to material gap. The arc length is set to 70. The arc control is at 50. The inches/minute are at 220. The weld is reasonable. I would prefer more weld width, and less build up. I am trying to get a fairly flat weld. There is a slight showing of penetration on the other side. The carriage is at 80% feed. There is a 1/2" thick piece of copper on the backside of the material, and the material is clamped the entire length to it. The weld is about 3/8" wide and 1/16" tall. I am new to this forum. It was suggested by our welding supplier, Liquid Air. If anybody can help, I would appreciate that. Thank you Stephen

[morpwr]

Help Needed Please Aluminum MIG

Is there no one with aluminumn MIG experience doing long welds?

[ryanjones2150]

Learning to MIG Aluminum

That level of welding is far and above me. Wish I could help.

[morpwr]

Thank You

Thank you for being honest. Rare thing these days. I just thought with such a large membership, somebody would have some experience. Thank you, Stephen

[Tryagn5]

I am trying to weld .09 thick 5052 aluminum tubes. They vary from 15", up to 30" in diameter. The tubes are five feet long. I made up a linear welder, using a CAT 1 welding carriage, to take the MIG gun along. I am currently using a 350P with aluma pro push pull gun. There is 5356 .047 wire in the welder and argon for gas. The linear carriage has a maximum speed of 36"/minute. So far I am using a 1/2" nozzle to material gap. The arc length is set to 70. The arc control is at 50. The inches/minute are at 220. The weld is reasonable. I would prefer more weld width, and less build up. I am trying to get a fairly flat weld. There is a slight showing of penetration on the other side. The carriage is at 80% feed. There is a 1/2" thick piece of copper on the backside of the material, and the material is clamped the entire length to it. The weld is about 3/8" wide and 1/16" tall. I am new to this forum. It was suggested by our welding supplier, Liquid Air. If anybody can help, I would appreciate that. Thank you Stephen

.09 thick material and you want a wider weld bead? Why?? .09 is hard for even a 350p to do, espically set up as a robot/automation style.
Anyhow if you want to increase weld size, slow your speed and increase your voltage...but im betting the results will be poor. Also if you do burn through that copper backing plate is going to destroy that weld.
Kevin

[morpwr]

Thank you

I did not realise that it was difficult to weld. I will try a little more voltage, which is arc length in pulse mode. Theoretically a longer arc cone should be wider at the bottom, and give me a wider weld. Thank you for the suggestion.

[WillieB]

I think most of us would TIG that material. It isn't good news for fast production.

[Tryagn5]

I did not realise that it was difficult to weld. I will try a little more voltage, which is arc length in pulse mode. Theoretically a longer arc cone should be wider at the bottom, and give me a wider weld. Thank you for the suggestion.

So why do u want a wider bead?? Also if you leave a slight gap you will increase pentration. However its going to be a very fine line between gap and burn through.
Kevin

[morpwr]

Wide and flat

I was trying to get a flat weld with no real build up. The weld we have now is 3/8" wide. I thought that a wider weld would also be flatter, and more aesthetically pleasing. I thought if the puddle ran down to the copper, that would be 100% penetration.The puddle does not seem to stick to the copper. I will increase the inches per minute, which will also increase the amperage, then adjust the speed to avoid those holes. Thank you for your guidance. TIG does a nice job, but is to slow for our application. Presently a 60" long weld is about 2 minutes. Weld quality is reasonably good, just trying to make it slightly better.

[ryanjones2150]

Learning to MIG Aluminum

You have some pictures of the whatsit you're welding? I'd like to see this thing.

[Tryagn5]

I was trying to get a flat weld with no real build up. The weld we have now is 3/8" wide. I thought that a wider weld would also be flatter, and more aesthetically pleasing. I thought if the puddle ran down to the copper, that would be 100% penetration.The puddle does not seem to stick to the copper. I will increase the inches per minute, which will also increase the amperage, then adjust the speed to avoid those holes. Thank you for your guidance. TIG does a nice job, but is to slow for our application. Presently a 60" long weld is about 2 minutes. Weld quality is reasonably good, just trying to make it slightly better.

Ok. Now i got an idea of what you want. So to get a flatter bead there must be a place for the weld to go. So either leave a gap in the material or bevel it. Since it is so thin a gap is the only way to go, and yes a copper backing plate acts like a catch for the weld pool. However if the pool is to hot it will burn into the copper backing plate and produce a bad weld.
Now getting 100 percent pentration and a small bead with aluminum is going to be difficult in a single pass. Now if you could do a top pass then a bottom pass it would be easy. Doubt you can. This project is going to be a balancing act between speed, bead size, gap and voltage. Its will be difficult but not impossible. You do have the right machine. I would be contacting miller to see if they had any pulse programs to try. Fyi i did something similar to this with a lincoln 350mp, rather it was long sheet welds on aluminum. Once dialed in...which took a while it went very fast. Just had to get over the learning curve.
Kevin

[morpwr]

Have to figure it out

Tried upping the ins/min to 240/250/270. The materialwill tolerate 240 well with good penetration. At 250 you are close to burn through, and any small gap will hole through. At 270 after you go six inches, it burns through. I will try and take some pictures of the welding, and the apparatus we are using. Then figure out how to post pictures. Thank you for the help so far.