Aluminum Help Please

[RCGRT]

Can anyone please give me some suggestions as I am new at this. I tried running a few beads on some 1/8 6061. I cleaned the plate with a scotch bright hand pad, then wiped it clean. I'm using 3/32 Ceriated (sharp point), CFH@13, 3/32 4043 filler. NO.6 cup (no gas lens). I'm curious why the bead was coming out so wide? they're anywere from 1/4 to almost 3/8" wide. They are also very dirty, I could see black stuff floating in as I dipped the filler (not sure if this was coming from the parent material or filler), and they even feel rough or gritty. I tried the the balance at 20 and then 10 for max penetration, 125 - 150 A, and tried 100 to 125 hz. I noticed as I pull the electrode away from the part, the arc widens, how close should the electrode be held to the part? Any help would be great.

[Craig in Denver]

TIG likes a short arc, try for 1/8" or less. A #6 cup is pretty small for learning, try a #8 if space allows. Stickout is more important with alum, 1/8" with a #8 cup. A gas lens is more forgiving with stickout. The black peppering is probably from contamination. More penetration = less cleaning; however don't go to 'full' cleaning without any penetration.

CFH is good and 3/32" filler is too.

A wide bead is either too hot or too slow.

What welder? Do you have a pedal or is this lift arc; etc? If you'd like, you can jump up to User CP at the top left of the page and fill in you signature with this info.

[RCGRT]

Ok, that all sounds good. So where do you think the contamination is coming from? Stickout was probably about 1/4" or less, but not 1/8. So less amps will give a narrower bead? what about penetration? I read another thread where the guy was saying he believed his 4043 was causing the problem, that 5356 made the difference? Sorry about that, I'll fill the User CP out here shortly. Its a thermal arc 185 AC/DC. ( I wanted a Dynasty, but $$) running HF. My main concern here would be to find out where the contamination is coming from, could it be the tungsten maybe, I dont think i dipped it or touched the filler on it. Does the angle of the point affect the arc in anyway, or bead shape?

[Craig in Denver]

Ok, that all sounds good. So where do you think the contamination is coming from?

Well, a week ago, I thought I knew. Now I don't. Alum seems to be a mystery metal.

Stickout was probably about 1/4" or less, but not 1/8.

Tonight I tried making the tungsten flush with the end of the cup; zero stickout, and it worked fine. Stickout is highly dependant on the weld layout (butt, open butt, lap, fillet, etc) and position (vert, horiz, flat, etc)

So less amps will give a narrower bead?

Yes, as will faster travel speed.

What about penetration?

I can't answer this without infusing my perceptions; which maybe diluted.

I read another thread where the guy was saying he believed his 4043 was causing the problem, that 5356 made the difference?

I can't tell the difference, which disappoints me. 4043 turns black when anodized and 5356 doesn't like temperatures above 150* (after welding, like a cylinder head).

Sorry about that, I'll fill the User CP out here shortly. Its a thermal arc 185 AC/DC. ( I wanted a Dynasty, but $$) running HF.

The TA is a good choice.

My main concern here would be to find out where the contamination is coming from,

Yep, you, me and a thousand other guys.

could it be the tungsten maybe,

If the tungsten doesn't have a glob of alum, just above the ground taper, probably not. Notice the arc color of a freshly ground tungsten (pale yellow), if that color changes, grind your Tu.

I dont think i dipped it or touched the filler on it.

If you haven't dipped it (filler or base metal), you're ok.

Does the angle of the point affect the arc in anyway, or bead shape?

Yes, a sharp point = a shallower weld. A blunt point = a deeper weld. It's somewhere on Arc-Zone.com, but I can't find it.

[ace4059]

you are running it too slow. I like to run it hot and fast.

[GerryR]

Wipe your filler rods down with acetone before using them. They oxidize just like any other AL.

[RCGRT]

Is the oxidation on the filler rods something that cannot be seen? As they are fairly new and appeary very shiny and clean?

[RCGRT]

Well I have tried all that was suggested above. The bead still appears very grity like, and not shiny at all. Also on my last pass I noticed the very tip of the tungsten was a very clear purple-ish blue color, right on the very tip, above that turned a bit yellowish gold. Whats up with that?

[welderdude402]

Not long enough of a post flow time...the tungsten is gettin contaminated by atmospheric air before it cools completely off.

[thunder71]

your to cold turn it up :with a #7 or #8 cup