Tig tungsten question

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When tig welding with a 3/32 2% thoriated tungsten, the tungsten turns blue. There is no balled up filler rod, base material or anything on the tungsten, it just looks blue. Seems to work fine...just weird looking. hmmm....any suggestions? I am running a PT185 with pure argon set a 15 cfh. at about 80 amps.
Reply:probably heat tempering on it, mine do the same thing, usually blue or light red, and sometimes purpleStangnetShop Full Of Stuff. Joey
Reply:Dont stick your tungsten out so far and or  increase Argon flow. Best fix would be a water cooled torch set-up."after a long day of doing nothing...its gooood to kick back" Pumbaa
Reply:Increasing postflow might help too.
Reply:May be 4% Thoriated tungsten..
Reply:Most tungstens turn blue because at the end of the weld the weldor raises the torch to where the tungsten is pointing upward. Argon, being heavier than air, wants to exit the torch and drop toward the floor. This leaves the tungsten without a shielding gas and oxygen is then absorbed and creates the blue oxides on the tungsten. At the end of a weld the torch should be held in the downward position just as if welding. This allows the argon to shield it and keep the oxides from froming.
Reply:After you extinguish your arc hold the torch in place as so not to disturb the sheilding gas around the tungsten until the tungsten has cooled make sure your post flow is set long enough so the electrode is no longer red in color.  The discoloration is from the formation of tungsten oxides and is detrimental to the welding process it can contaminate the weld and it increases the resistance of the electrode increasing the heat input into the tungsten.Ron ShopFloorTalk Millermatic 350P, M-25, M-40 gunsDynasty 300DX, Coolmate 3, Crafter CS-310 TorchTrailblazer 302, 12RC, WC-2430A spoolgunSpectrum 2050Thermal Arc Plasma Welder PS-3000/WC-100B