Gearing up to weld aluminum

[SirLesPatterson]

I've had a Lincoln Power Mig 200 for 10+ years now, very happy with it. I just purchased a spool gun and will be adding a second thank with pure argon.

I work mostly with scraps of metal I collect here and there and I cast aluminum from odds and ends so a lot of it is unknown or mixed alloys. I'm wanting to deal with thick material now but might also want to do thin stuff later.

So I turn to the brain trust here... Is there a general purpose aluminum wire type that might best get me started?

Thank you.

[oxford]

I can't say so much for MIG but 4043 is pretty much the general purpose rod for TIG.

[vpt]

I agree, I use 4043 for most general jobs with TIG. However it is very soft and may not feed nice even out of a spool gun.

[MrFluffy]

If your welding lots of unknown grades, some of them simply will not weld so its worth doing a test on one before machining it into some complex shape in prep.
I did a clutch cover extension way back for a motorcycle, machined up cover plate, machined original housing, added fasteners, turned the extension from a piece given to me, came out really nice, last job weld the finished extension into place. Turned out to be an unweldable grade. Whole job junked.
At the time I thought it was my workmanship with a welder, but since I've welded a lot of graded aluminium's that are weldable and some which are listed as awkward, and now I know pretty much it was down to the grade of the extension piece.

[danlb]

Let me know how that works for you. I just bought a TIG welder and am going through a learning curve myself.

One of my first practice attempts used some bar stock from Lowes. I prepped it, set things according to the book and tried to melt some aluminum in a reasonably straight line.

I ended up with black blobs precipitating out of the aluminum. Lot's of the alloys do not weld well. For learning it would probably be best to start with known materials.

There is a web page ( http://www.thefabricator.com/article...luminum-alloys ) that mentions the best filler for various alloys.

In part, it recommends 4043 filler for 3XXX, 4XXX and 6XXX alloys. 5356 filler is recommended for 5XXX alloys. It's not recommended to weld 7XXX or 2XXX alloys because it cracks. 1100 filler is used on 1XXX, though it sounds like the 4043 will work too.

Dan

[dp]

The spool gun I adapted to my Lincoln welder came with ER4043 and works quite well. http://metalworkingathome.com/commun....php?topic=5.0

[LKeithR]

If you're mig welding alum. plate, bar, angle, etc. 99% or more of the material you'll encounter is going to be 5052, 5086, 6061 or 6063. We have welded this stuff for years and for all those alloys 5356 is our go-to wire.

[SirLesPatterson]

Thanks folks, that will get me going!

[oxford]

From what I have read the 5356 will give better results to the appearance if the piece is to be anodized after welding. I know for a fact that 4043 rod used on 6061 alloy will come out very dark and noticeable after anodizing.

[outlawspeeder]

I am in the same boat. Had a MIG 175 for ten years. Looked at aluminum and figure a way of bolting it together. This last weekend I scored a hell of a deal on a Lincoln 275 TIG welder.
Still getting the supplies but tonight I got a bottle of argon. I did get a real pass on 4043 without it turning to melting butter. There is plenty of room for improvement there. From what I have learned. CLEAN is the key to weld any aluminum.
I was told "When you look at your hot spot (the spot you are melting) if you see a crust, you haven't cleaned it well.

[Mr Fixit]

Hello Group,
Not to hijack this post but I too am just getting into TIG welding. My question is the high frequency setting called the HF Intencity on a syncrowave 250 machine for TIG of both aluminum and mild steel.
What do you set it to 0-100 range or scale. By the way this is a knob setting that is in the lower part of the machine down where the leads, 120v outlet and solenoid are located for those that don't have one.

TX Mr fixit for the family
Chris

[BigMike782]

"Use control to change amount of
HF energy used to start and maintain
the arc. Set as low as practical
to prevent interfering with electronic
equipment"

For Miller manual.
My guesss is almost any of these machines are set to max. Anytime there is an arc start issue the first thing is to crank the intensity all the way up.......whether it fixes the issue or not.

[danlb]

I did get a real pass on 4043 without it turning to melting butter.

I'm glad that you mentioned that. I was playing with my new welder, getting used to the controls and settings. I was getting virtually no puddle with the settings that I thought would work on a 1/2 inch diameter 6061 bar. I cranked it up a bit and made another pass and it made a nice wide pool as I ran the torch down the 4 inch length of the bar. When it solidified it looked almost like it had never melted. It's texture reminded me of melted butter that I had run a hot knife over and it put back in the refrigerator.

Is that what it's supposed to look like when you are doing it right?

Dan

[macona]

Well, yes and no. Fusion welds are useless when it comes to aluminum. You must use filler. Just running a pool down the length of the rod does not mean anything. What will matter is your technique of adding filler as you go. That's where things get tricky, creating a puddle and getting filler in without melting the rod before it gets into the pool and back out all while avoiding the tungsten.

[Highpower]

.....That's where things get tricky, creating a puddle and getting filler in without melting the rod before it gets into the pool and back out all while avoiding the tungsten.

And all the while keeping the tip of the rod within the shielding gas envelope. Simple, right?