Welding Tips and Tricks

Hey guys. I am fairly new to tig welding and teach myself through the Youtube videos. I have attached a picture from practice tonight. Getting close to the end of the weld the tungsten popped and the tip turned blue. I am not sure what caused this. My settings are below. If anyone has any ideas please let me know. Also any tips would be welcome
Material is aluminum 1/8"
Welder is arc master 185
2% lanth. Tungsten
Amps 100
Hz 150
Cleaning 35%
Thanks Drew

The tungsten doesn't look to bad. The color might just be from being real hot after a long run. Or if it happened just as you got to the last edge of the sheet some impurities might have been pulled from the cut edge.

Tungsten exposed to air without shielding. Since it happened at end of weld increase your post flow to protect tungsten and weld. You want to shield tungsten until it cools down some. Make sure to hold torch over weld termination until post flow is done. Don't just terminate arc and set torch down.

I assume your stick out in that pic, that you just pulled tungsten out that far to make it easier to photograph.

Were you at the edge of the work piece? Turbulence can draw in some air to your gas cloud. Air is not a good thing there. Different torch angle can help. A gas lens is also helpful. Keep stickout short with a standard collet, and arc short is always helpful. put a backer of aluminum behind your sheet to prevent the gas from blowing past. Angle your torch to send gas around your work.

I don't think it's a big exaggeration to say most TIG problems involve gas coverage. I feel if the gas were visible, most problems would be easily fixed. Short stickout, short arc, near perpendicular torch angle, good equipment free of leaks, a backer preventing gas from mixing with air from behind the joint all are good practices.

Any chance you stepped on or briefly kinked your gas line?

You said it "popped", so that suggests either a brief interruption in gas flow, or a disruption locally from something in/on the metal that abruptly "boiled off".

Steve S