MIG aluminum

[TXWelder]

I've got a HH140 that I bought specifically to use around the house and for aluminum. The sales guy said it would wel aluminum, the manual says it will, you guys say it will.

How come my Al welds look like CRAP?!?!? What am I doing wrong???

I've run two different types of wire, I bought a stainless brush, I got "fast and hot" like they say you should. Why do my welds all look like singed boogers lumped ontop? About the only thing I can think of is that I run mix rather than straight argon, but can the gas make that big of a difference?

I'll try to post some pix of the crappy welds tomorrow so you can see what I'm talking about...

This is distressing......

[MAC702]

I don't know anybody here that would RECOMMEND that kind of welder for welding aluminum. That said, there has been much discussion here on how to do it as well as the machine will allow it.

The gas makes a huge difference. Don't bother trying again until you get 100% argon. Then try again, and tell us how it's going.

[BillC]

What material thickness are you welding?

[BDKS]

Thought I read on this board the gun liner needs to be changed.

[MAC702]

Thought I read on this board the gun liner needs to be changed.

That will help with the reliability of the feeding, but shouldn't affect weld quality.

[Fishy Jim]

You'll want to run a teflon sleeve in it. Most issues I've ever heard of with mig and AL are because the filler is too soft to shove down the whip without kinking against its own resistance. That's where push-pull and spool guns come in, they don't have very far to go after the rollers.

[dda52]

Yup to what Mac said....don't even try it again until you get straight Argon. Alu hates CO2 and I thinking you have found that out?

As to liner, I would say get it. It made a huge feed difference with my MM135. It is better to have two guns..one for steel and one for alu. Keeps you from having to switch out the liners all the time. FWIW, the Miller p/n is 194014 for the teflon liner. ROCK said way back when it would fit the Hobart guns as well.

What filler are you running? 4043 will work best. 5356 will feed better, but the welds will be ugly and cold. For that matter, the 4043 welds will be a little cold as well. Don't run it in short circuit transfer. Get it hot..almost maxed out and it will hit spray. That is where you need to be running alu. I found the .030 4043 to be the best producer. The little MIGs are not big enough to do much...1/8" max. Absolutely nothing critical either.

[TXWelder]

Yup to what Mac said....don't even try it again until you get straight Argon. Alu hates CO2 and I thinking you have found that out?

OK, I'll try some straight argon. Great...now I have to buy a new bottle!

As for feeding: my HH140 feeds 4043 just fine. I've burnt probably 1lb of the 2lb sized spool I got and never had a feeding issue, so I guess a liner is mute.

Don't run it in short circuit transfer. Get it hot..almost maxed out and it will hit spray. That is where you need to be running alu. I found the .030 4043 to be the best producer. The little MIGs are not big enough to do much...1/8" max. Absolutely nothing critical either.

Short circuit transfer??? I've got it set-up DECP - Electrode Positive as per the manual...is that right? All I want is 1/8" or less. Why, "...nothing critical...?" What good is welding something if you can't do anything 'critical' with it????

[HazMat55]

I think the "critical" refers to someone's life riding on your weld. i.e. rappaling, climbing equipment, airplane parts, etc.

[Fishy Jim]

so I guess a liner is mute.

Liners aren't supposed to make noise. Moot and mute are quite different.

[timw]

A quick rule with Aluminum, no gas with Oxygen in it. Which leaves Argon and or Heilium. Maximum cleaning is required. No oils, wax they contaminate. The worst Aluminum I ever welded was refrigerated semi trailer floors. Always have animal fats and forklift lubricants plus the insluation will out gas with the heat.
A friend ask me to look at his HF MIG yesterday, he was tring to weld Alum with it and having no luck. After several attempts I finally figured out that he had an old 4" spool of wire that was covered with oxidation. Talk about issues!
Also keep you torch as straight as you can to make pushing the wire easier. This goes with all MIG welding.

[lars66]

an argon helium mix will weld hotter on al.

[dda52]

OK, I'll try some straight argon. Great...now I have to buy a new bottle!

As for feeding: my HH140 feeds 4043 just fine. I've burnt probably 1lb of the 2lb sized spool I got and never had a feeding issue, so I guess a liner is mute.




Short circuit transfer??? I've got it set-up DECP - Electrode Positive as per the manual...is that right? All I want is 1/8" or less. Why, "...nothing critical...?" What good is welding something if you can't do anything 'critical' with it????

Eventually the liner will plug up with alu shavings. Switching to teflon eliminates that problem. Short circuit is the transfer that your machine operates in the most. The voltage is not sufficient to get into spray much, if at all. The HH140 just isn't a big enough machine to be a proficient alu welder. You have to operate it right at the end of its power range to get it to work with alu. It will do it, but the welds won't be that consistent and will be a tad cold. When I compared my welds from my MM135 and then with the 210 and spoolgun, they were like night and day. The 135 weld was cold, while the 210 weld was so hot, it almost blew through. If you are very careful, and pay attention to all the parameters, I have no doubt that you will get it to weld alu just fine. I did for awhile. It was fun trying to get it right. Took lots of practice and patience.

[TXWelder]

Liners aren't supposed to make noise. Moot and mute are quite different.

Great...now we've got grammar police here! I'm having enough trouble just learning how to weld w/o having to worry about how I type!!!

[TXWelder]

A quick rule with Aluminum, no gas with Oxygen in it. Which leaves Argon and or Heilium. Maximum cleaning is required. No oils, wax they contaminate.

Thanks for all the help!

I was going to post some pix, but I seem to have acquired a virus on the old PC and I'll have to fix that before I can upload.