Welding Tips and Tricks

On Monday I start TIG in my MIG/FLUX CORE/ TIG class. Tonight I was doing a little practicing on aluminum. Of the TIG welders I have I use the HTP 221 and the Thermal Arc 185 for aluminum.

Tonight I was using the Thermal Arc 185........set as follows.

1 1/2 3/32 Lanthanated tungsten

25 CFH on the Argon

100 and 120 Hz on the frequency

15 on the AC balance.

Everything worked good. My question is this....as I we as welding I noticed black specks in the weld pool. Is this typical for aluminum???

I did wire brush one of the small .125 plates I was welding on but that didn't seem to make a difference.

Argon flow seems very high, what cup are you using, and gas lens or not? S/F.....Ken M

I'll run up to 35 chf on aluminum, with a gas lens.

I'm not familiar with the ThermalArc's AC balance characteristics, but, in general, too little cleaning action can cause this IF your material isn't clean enough to start with. Too MUCH cleaning action can cause tungsten "mist" to migrate to the weld pool, and cause little black dots to scurry around in the puddle.

I prefer to use the minimum cleaning action that will get the job done.

Steve S

Here goes with the pics..............

Don't mind the inconsistency in the welds......I am still learning. So of these may have been done on pulse. That really doesn't matter. The thing is I tried again today and I still got several (1 or 2 specks) in the weld pool. I am trying to keep the filler rod in the shielding gas between each dab! I see good etching outside the weld bead which does indicate cleaning !

Good job on those beads!

Is your welding table made of mild steel? Are your gloves dedicated to aluminum or do you use the same pair for all your welding?

Nils wrote:Is your welding table made of mild steel? Are your gloves dedicated to aluminum or do you use the same pair for all your welding?

Table is made of steel. I use a soft glove strictly for TIG welding although I use the same gloves for TIG welding carbon, stainless and aluminum.

How do my welds look???

I tried again last night. I played with the AC balance, the argon pressure, and cleaned and wiped off everything with acetone and I am still getting some black specs in the weld pool. I tried just running the torch with no filler rod and I got some black specs. This is annoying me as I want good clean welds.


Any help is appreciated!!!

Might be time to add a dryer to your argon line (downstream from the flowmeter). You may be getting damp gas. This is cheap to test... Get a cheapo Harbor Freight in-line air-compressor dessicant and give it a go.

Also, have you ruled out any chance of a tiny leak in your gas line? O-ring lubricated in the back-cap? These are unlikely with the pictures you posted, but it's possible a very tiny leak could be doing this.

Good seal between your cup and torch head?

Steve S

Hi Steve,

You wrote... "O-ring lubricated in the back-cap? "

Is there any special lubricant that should be used? Or can plain oil or Vaseline be used.... sparingly?
(Newbie TIG welder here, reading a lot and trying to learn.)

Thanks,
Dan

Hey, Dan,

Typically, a dielectric grease, like the silicone "Spark-plug boot grease" you can buy a packet of for 99 cents at the auto parts store is fine, and that 99 cent tube will last a lifetime. It's not a big requirement, but that o-ring can tear or leak during disassembly/reassembly if it's not lubricated, and the "boot grease" won't conduct/leak electricity, or break down.

Silicone lube is what comes with a cup/backcap kit, when you buy a complete set.

Don't gob it on, though. getting the o-ring "shiny" is plenty. You don't want "squeeze-out" to make it's way out the business end of the torch.

Steve S

Those beads look pretty good! It's tough to eliminate all the oxides ... But if you're cleaning everything with stainless-like care, look at your filler metal. You could be introducing oxides that are on the filler. From there, check all gas connections & make sure there's no moisture anywhere ... That can cause specs that don't ever seem to go away.

I posted a video with 6 tips about adding filler ... very basic & best practices, but it's a start if you care to watch. Here's the link: http://youtu.be/ekll1g1srpI

Good luck!

When this happens to me, I usually stop welding ans try to clean it off some more with a wire brush. I'd that doesn't work I wipe some acetone over it.