[going4speed]

Two different metals are exhibiting the same issue. Start a weld and form a puddle and once the puddle is formed the steel just vaporizes and creates a blackened electrode and leaves a brown soot on the metal. The resultant weld looks like volcanic rock embedded into the metal. I shut it down when it does this. Tried to weld on both 1018 and 304 plate and getting the same result but not in all areas of the metal. At times I can achieve a fine arc/puddle and weld out the bead.

As for skill, I have been tig welding for two years and can lay down what I consider a B- bead. Image attached is of normal production when not having above issue. (Yes the undercut is ridiculous)

Equipment is:

WP20 2% 1/16 lanth gas lens setup #8 cup (tried new lens and cup as well as back cap to eliminate potential leaks)
HTP221
Filler rod used is ER70-S6 and 308L
Gas hose is new and tight on both ends

Prep:

Ground shiny metal and acetone cleaned.
Electrodes ground on tungsten grinder so dedicated diamond wheel

Ideas?

Thanks

[exnailpounder]

Pics of the metal and tungsten would help.

[Poland308]

You may need to get a flow meter that goes over the end of your cup to check cfh. You may have a gas solenoid that is sticking or not opening at all. Checking cfh at the cup will verify you are getting proper flow. You may have a regulator that has gone bad or a hose that has collapsed on the inside causing a restriction you can't see. You said the hose was new. Did you have the problem before you changed hoses or after?

[ScottFc3s]

Sounds like lack of gas flow or wind blowing your gas away.

[Otto Nobedder]

I can't say I've encountered an intermittent gas flow issue, but I see a simple way to check. Set a good post-flow time, say 10 seconds, and the instant this issue happens, break the arc and listen for gas at the torch.

A loose connection at the gas solenoid could cause random loss of gas flow.

Steve S

[Otto Nobedder]

I've also had a coolant leak in the torch head produce the symptoms you describe, but I'm damned if I can see that being an intermittent problem.

Steve S

[motox]

you set on T-2 not 4?
craig