[Poland308]

The brown smudging almost still looks like a gas issue. What size cup are you using ?

[Gene.243]

That's with a #8 cup so 1/2 inch.

[exnailpounder]

Gene...just a thought I have...what exactly is your base metal? Is it galvanized and you ground off the galvanizing? The reason I ask is that I recently did a project that was ferritic stainless with a galvanized coating. Even though I ground off the galvanizing to shiny bright metal, the coating had penetrated far enough that it was an absolute nightmare to weld and my tungsten looked just like yours. The zinc vaporizes and the burnt particles jump right onto the tungsten and crap it up. Millscale will do the same thing as I am sure you have noticed. Your pic of the tungsten after you just did the puddle doesn't really look like a post flow problem and your tungsten balled a little but looked good. Its when you move that your getting crapped up right? You just might have contaminated base metal. You cannot weld TIG weld through any sort of contamination. You metal could be crapped up and you don't know it. That grayed out bead in the middle of the last pic suggests using too much heat to get a puddle. Your ideal TIG bead should be shiny bright metal when you are done. Get some brand new metal and try that. Cleaning up rusty old metal may be your problem.

[Gene.243]

Gene...just a thought I have...what exactly is your base metal? Is it galvanized and you ground off the galvanizing? The reason I ask is that I recently did a project that was ferritic stainless with a galvanized coating. Even though I ground off the galvanizing to shiny bright metal, the coating had penetrated far enough that it was an absolute nightmare to weld and my tungsten looked just like yours. The zinc vaporizes and the burnt particles jump right onto the tungsten and crap it up. Millscale will do the same thing as I am sure you have noticed. Your pic of the tungsten after you just did the puddle doesn't really look like a post flow problem and your tungsten balled a little but looked good. Its when you move that your getting crapped up right? You just might have contaminated base metal. You cannot weld TIG weld through any sort of contamination. You metal could be crapped up and you don't know it. That grayed out bead in the middle of the last pic suggests using too much heat to get a puddle. Your ideal TIG bead should be shiny bright metal when you are done. Get some brand new metal and try that. Cleaning up rusty old metal may be your problem.

I had been practicing on aluminum when I was getting fouled tungsten. The rusty mild steel was an old practice piece from the scrap bin. It was cleaned with a sanding disk on a grinder then wiped with acetone.

This weld is on 1/8" Al.

[Poland308]

Is there any chance the atmosphere in you shop is tainted with chemicals? Paint booth? Salts of some kind. Or sulphur ?

[CanMoulder]

For starters
You all are Awesome
i do more reading than posting

i use an old Hobart 220v tig welder
set at about 60-80 amps
argon is at 15-17
Had a mold break last week
block is p20 using a p20-mod Welding rod
i have never had a problem with this set up before
but last week i was seeing allot of porosity and spent a ton of time digging it out and trying again
i found that the fitting from the hose to the torch was loose, the fitting from the hose to the machine was loose and lastly the gas line from the tank to the machine was loose.
fixed all that and it seemed to get better
this week the other side of the tool broke in the same spot
and it was the same crap.Porosity. Something i noticed was that half my tungsten was blue the other half was OK
Today i sat down before work and read this post. Looked at the pics and
Than i Dug through all the dusty old crap here and rebuild the torch everything got new or slightly used.(welder on Monday is going to hate me but OH well!!
and magic tungsten looked awesome and no more porosity

Thanks all saved my hair line today

Kev

[Gene.243]

Is there any chance the atmosphere in you shop is tainted with chemicals? Paint booth? Salts of some kind. Or sulphur ?

None that I know of.