[ekbmuts]

Guaranteed I'm not the first person to post with a problem with grainy looking AL welds.

I'm doing these aluminum frames from 1" x 1/4" 6061. Tricky welds because the welds themselves are only about an inch long and then you're off the end.

Found a neat trick to prevent blowout though: weld from the outside in. Then there's some meat to absorb the heat.

Anyway... all was going well and then all of a sudden I'm getting a grainy bead. Don't know why. Continued anyway. It's not like these welds have any structural requirements.

But what's up with this?

I'm running my PT185 at 185 amps, 1/8" red tungsten, 50/50 cleaning/penetration, 100% argon, no pulse, 3/32" 4043 filler rod and I'm going from corner to corner to allow the material to cool down. I'm not welding how or preheated AL. It's room temperature when I start each weld.

I'm stomping on that food pedal and adding filler rod almost immediately. I'm not massaging the piece with low amps. I'm just going for it.

I am in a slightly sometimes breezy room. But I don't remember feeling a draft. Could have missed it.

I'll post some shots tomorrow when I have my camera to hand.

But any ideas in the meantime would be appreciated.

Thanks as always.

Jon

[ekbmuts]

Here's some pix:

_MG_0001.jpg

_MG_0002.jpg

_MG_0005.jpg

First two were okay. Third shot shows grain (even if it is a bit out of focus).

[BillE.Dee]

I often get the same outcome when I use 4043 filler. I've noticed that when I switch to 5356, the graininess goes away with the same settings. A friend of mine told me too much heat even after I get the puddle and move along, probably not fast enough. I'm still in my learning curve that from what I've heard is not a ramped up situation but straight up. Hang in there and keep practicing is all I can offer.

[cj737]

As said, 4043 gets grainy with accumulated heat. 4943 or 5356 comes out better. Also, adjust your balance to 65/35 and you can clean them up some more

[ekbmuts]

Great - thanks guys.

I'll get some of both those rods, 5356 and 4943.

Jon

[cj737]

Great - thanks guys.

I'll get some of both those rods, 5356 and 4943.

Jon

Any particular reason you’re using Thoriated tungsten with aluminum? Lt Blue or Gray (lanthanated or ceriated) are the preferred types for ally welding.

Looking closely at the pictures, that “crater” at the end of your weld needs to be eliminated as a best practice. You can add “j-u-s-t” a bit more filler right at the end as you taper the heat to fill that, you definitely need to taper your pedal as you finish your weld, and hold the torch still over that spot after the arc stops to let Argon flow over it and cool it. That reduces the shrinkage, and what man doesn’t want to avoid shrinkage?

[BillE.Dee]

Jon, just wondering what you are using to clean the aluminum. It just appears to me that there is a course wire brush. I'm far from professional on this but I only use a hand held dedicated stainless brush and only near the weld area. Thanks for sharing and keep up the good work.

[ekbmuts]

cj and BillE, Thanks for your feedback.

On the tungsten and why I'm using red - that's a good question. I always thought red was preferred. Then I learned that blue tops all of them. I have tried brown with some success but never grey. I'll try and get my hands on some and try it out.

Agreed on that crater. I've been working on that. I'll take your advice.

In terms of cleaning, I think I'm using far too coarse a brush. The ally comes with a print on it that I haven't been able to remove with acetone for some reason so I'm having to brush it off. I don't know if the coarse finish that I'm leaving with my current brush is contributing to my problems or not. Perhaps it is?

If you take a closer look at those photos (as I just did) you'll notice that on the grainy weld there appears to be some "burn" on the left of the bead. Now that I'm thinking about this, I think that might be the breeze blowing the argon away in addition to whatever other problem I was having.

In either event, thanks for listening. Thanks for your feedback. It's all helpful.

Jon