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Dirty Weld and bubbles in it.

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Dirty Weld and bubbles in it.

Postby tenglema » Sat Oct 14, 2017 7:30 pm

Greetings, fellow welders.. I just bought a Lincoln Electric Square wave 200 and am trying to "self teach" myself how to do things. Not going well.
I'm trying to put together my first project, my weld table.
I'm using soft 1" square steel tubing and Tigging it together.

I've watched many many training videos on the web and putting their advice to practical use has been difficult.
My main problem now is that the finish weld looks "dirty" with small or large bubbles in it. Certainly not like the welds you see in the training videos. I've tried everything I know of on how to fix this. Super cleaned the metal, (down to bare metal); cleaned it with Acetone; tried all kinds of different gas flow settings; different speeds; different torch angles, different arc length; different speeds.

Nothing seems to fix the problem.

Need some help from the forum on how to fix this and get the "pretty" welds you see in the videos.

Anybody have any pointers for me to pursue?


Beginning TIG welder...
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Re: Dirty Weld and bubbles in it.

Postby cj737 » Sun Oct 15, 2017 7:44 am

It sounds like you’re getting porosity in your welds. That can be caused by insufficient gas flow, poor torch angle in that area, too much tungsten sticking out with too low a flow rate, or, the metal is pulling contamination through it (you don’t mention the wall thickness of the material).

Even cleaning the outside won’t prevent the interior grime from sucking up into your puddle. But I’m still leaning to gas flow issue. Have you dipped your tungsten into the weld, and not ground it back clean? Some pictures of your tungsten, cup, and work will help. And your gas flow setting.
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Re: Dirty Weld and bubbles in it.

Postby RayCJ » Sun Oct 15, 2017 8:18 am

If it's bubbled and almost looks like a sponge, it could also be from too much gas flow or possibly, you have a breeze or draft in the area. If the cup you're using has say a 7/16" opening, your CFH rate should be about 12. Turning the gas too high also causes air turbulence at the mouth of the cup which results in air getting mixed into the gas. Is the welding unit head within a few feet of your work? The fan might be blowing right onto it. Is your torch or lines leaking? The o-ring on the tungsten cap has to seal on the backside of torch head. Is your arc too long? If you're holding too far away, air as more chance to contaminate the argon. Are you holding too much of an angle?

Also, if you are welding over previous inclusions, the gas expands and pops on the second pass over.

Like the other poster mentioned, post pictures and give all the details of your setup.

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Re: Dirty Weld and bubbles in it.

Postby MarkL » Sun Oct 15, 2017 10:38 am

Is it possible you have the machine set to AC? Post a photo of settings on machine and the weld, I've got the same machine so might be able to help.
Lincoln Square Wave 200
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Re: Dirty Weld and bubbles in it.

Postby dave powelson » Sun Oct 15, 2017 1:48 pm

With tubing the inside needs to be clean for at least 1/2". Blow out tube lengths, wet wipe
sand/brush the cut ends clean, clean inside throat, check for any oil inside tubing and swab it
out if present.
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Re: Dirty Weld and bubbles in it.

Postby discap » Tue Jan 09, 2018 1:11 pm

Hello this is my first post to this Forum. I found it after having difficulties welding aluminum with my Lincoln Square Wave Tig 200. I upgraded to this machine from the old Square Wave 175. I was experiencing the same difficulties are the Original Poster. The difference is that I have welded miles of aluminum (possibly a small exageration). I tried everything on the cleaning front, to flow rates, to cleaning settings, to frequency to pulsing, new metal, old metal, red, green and blue tungstens. I finally was out of ideas.

I took it to my local dealers shop. Told them the problem and they looked at each other and kind of laughed. Yes they had seen this problem. They handed me a Gray banded electrode. I brought in the machine and plugged it in. Viola welds like a charm. 2% cereated is what is shown on the package. I have never used them before, but welds like a champ without even cleaning the new metal.

Hope this helps anyone trying to use this machine.

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