I are a luminum welder!

[Blondie_486]

HAWK,

I looked at the ol grey machine today and it is an IdealArc TIG 300/300 AC/DC Arc welder. I was doing some aluminum work yesterday and was welding new aluminum to old stuff. I cleaned both the old and the new thoroughly with a wire wheel on an angle grinder before beginning to weld.

Whatever was on the aluminum though didn't all come off and was getting some contaminants in the weld puddle and constantly had to keep increasing the amperage to purge it then back off again.

I remember in a previous post you said you liked the pulse option on your Dynasty because when you were welding aluminum you could use the pulse to shake the puddle and bring the contaminants up to the top. The whole time I was welding this job I couldn't help but wonder what it would be like to be able to use that feature to make the job a bit easier.

Despite all of the contamination I did manage to get a good solid weld and a nice looking bead too. So I guess that's what really matters in the end but it's always nice to "wish".

One more comment that does pertain to Shaky Jake's original post concerning the craters at the end of the weld. What I do is load the puddle with filler at the end and reverse direction and come back into my bead just a touch before backing off the pedal. It seems to work for me.

Blondie

[HAWK]

Blondie,

The Ideal-Arcs are great old machines. The contamination thing can be a real killer! I am taking a break right now to let the 200DX cool down. I am doing a repair on a .250" outside corner joint. This thing has been sitting in a trash compacter for several weeks and I cannot get it clean enough. I have ground out the old welds with aluminum grinding wheels, really worked it over with an angle die grinder & Scotch-Brite, wipe 3 times with acetone and dried with clean cloth. The puddle is really hard to form even with 75% helium/25%argon. No matter what I try the bead is full of contaminants. Even a high pulse rate is not helping me much tonight. It must be some horrible stuff that has gotten into the material. I am furious with it right now. When I figure it out, I will have learned something new. I hope this one is solved soon. It has to be back home Monday A.M.

[Blondie_486]

HAWK,

Good luck getting it clean, perhaps it's a chemical contaminant. Maybe it's something acetone won't touch.

Occasionally I find myself having to break out the stuff we prepped aluminum for paint with. Manafactured by DuPont called "Aluma Prep" it will actually etch the aluminum but wear rubber gloves while using it because it will burn just as bad if not worse than paint remover. We've got some stuff at work supposedly for cleaning aluminum before welding but it sucks.

Have you tried pre heating the aluminum before you start welding? I found that helped me the other day and what I was working with was 1/4" also. I've found that the hotter the aluminum gets the better it welds. Maybe the flame will burn the contaminants out?

Good luck
Blondie

[HAWK]

Blondie,

146" later I feel much better. I turned the pulser off and drop my balance to 65% electrode negative. It gave me the nice white permeter that shows good cleaning. I floored the pedal at 200 amps with the 75% helium/25% argon and got it really hot with that orangish flicker. When the flicker came I stuck the 4043 3/32" filler in and ran hard and fast until I got into a spot where I could not feed. I never pulled the filler out of the puddle. It started running good and I did not even back off the pedal-just cranked the travel until I was down to 2" of filler and smoking my gloves. It turned out pretty nice and I will sleep well tonight knowing I don't have to fool with it on Sunday!

[HAWK]

Blondie,

This stuff is NASTY!!! Take and look and tell me what you think.

[Paul Seaman]

Hawk

From what I see, looks nice, real nice. I like seeing your work, makes me want to work a little harder to be better. Practice, practice, practice!!!

[HAWK]

PJ,

Thanks. It is just really dirty material. Even at a high pulse rate I was not able to get a real good bead running. The one posted is at 200 amps, 65%EN, 14 CFH, 250HZ, pulse off. I was already furious with the work piece so it was really easy to run hard and fast once the balance came into tune. I just have not hit on what to clean this junk with. I guess anything and everything goes into a trash compacter. There's no telling what kind of chemicals have soaked into this stuff.

Sometimes I have to do the late night and weekend thing. My deal is almost final on the mobile rig and I'll be sticking to TIG with some MIG and STICK as a have to do. I already feel better getting out of the mobile work. I can feel my headaches easing off. Just get out there and do it. Make it fun or you won't want to do it.

[Blondie_486]

HAWK,

The bead looks nice but I can visualize in my mind what a tough time you had getting it there. Judging by the white along the edges of the weld it almost looks like battery acid has trickled along where the weld joins the base metal.

My best guesses would be;

1. The pores in the aluminum have absorbed the contamination and you haven't found out what to remove it with.

2. Possible alloy contamination in the aluminum. It is possible the aluminum was made with recycled material such as pop/beer cans and somewhere it has picked up a conatminant in the re-melting process. Recycled metals are never as pure as the ****** stuff. That's true even with steel.

I've gotten some bad heats of steel out of a re-melting facility in New York that was really nasty to weld. Perhaps that's the case here?

It looks like you got good penetration and the weld looks good, very uniform considering the circumstances I don't see how you could have done any better. That weld should stand the test of time.

If ever a time comes you decide to kick the Dynasty to the curb could you see if you could hit my curb? I'm afraid to go and demo one because I know I won't want to leave without one and right now I don't have the cash and now won't have the place to use it either.

Blondie

[HAWK]

Blondie,

This piece was supposed to be first quality 3003 when it was made. I would have used 1100 filler, but all I had in 1100 was .063 rod. I had to go with 4043 which is an alternative filler for joining 3003 to 3003 alloy. The white around the edges did not appear until I lowered my EN balance. I have always noticed this white perimeter when I am getting a really good cleaning action with the arc.

The Dynasty is a nice unit. I am looking to pick up a 300DX around the end of this month if all goes as planned. .250" with the high helium content usually welds just fine. I have even done some 3/8" fillets in a single pass on 6061T-651 without preheat and heavily swirling the arc to get a good toe wash. The bead I posted was not swirled-just straight lined with the filler staying in the arc.

I think with the history of this piece and customer I would have to go with the base metal has absorbed something that grinding, Scotch-Brite, and acetone just won't remove. I hope it will withstand the test of time. I certainly do not want to see it again!

[Paul Seaman]

Hawk:
I talked with a friend about what you are fighting he thought maybe this metal may have a high acidity in the base metal. He said if you can try putting 2 table spoons of baking soda into a cup of hot water scrub and brush till dry with a SS brush then weld as normal. I thought it sounded odd but any trick may help if the known tips didn't work.

Weld well

[Blondie_486]

PJ Seaman,

It doesn't sound odd at all. Baking soda is an alkali which will neutraiize an acid. Try it on corroded battery terminals it works wonders for them.

Blondie

[Paul Seaman]

Blondie:
The Alkalai part didn't sound odd the high acid metal is what I was referring to, my appology for not being accurate saying what I ment to say.

Anyway if it could help great if not it is a small amount of time for the exploration of a solution. Here lately I've been using 99% Isopropyl alcohol for cleaning, it does pretty good but no etching action since what I am welding tubing I don't want to miss any and end up with acid fumes if that is a possibility. Alcohol dries faster too.

Peace

[Blondie_486]

PJ Seaman,

Acetone, lacquer thinner, Xylol and Xylene all work well and flash off quickly. The Acetones and Xylols will cut oil and grease better than Isopropyl alcohol will though so if you have parts that have been subjected to grease the alcohol may not be as effective.

I guess it doesn't really matter what you're using as long as it's taking the contaminants off and not leaving anything behind that will contaminate the weld.

Aluminum is rather porous and is liable to absorb lots of things and retain them past grinding, wire wheeling and solvents can get to. Sometimes it's just a pain in the backside to work with!

Blondie

[HAWK]

PJ,

Thanks for checking. The sodium bicarbonate makes perfect sense. If I run into this again , I will certainly give it a try. I do appreciate your input. I thought I had seen all the quirky stuff, but I have not and probably never will!

[HAWK]

Blondie,

You mentioned xylene. It makes me thing back quite a few years and I wonder if toluene would do a better job. It is simply a benzene ring with a methyl group attached. What do you think? If it will work , I bet it would be hard to come by at the very least.