[reyesjr]

Hey guys just found this place while searching for some tig welding tips and it seems like its a great place to try and get some help. I work in a welding shop as a tacker/fitter. I can't get welder pay until I pass a MIG/TIG test. The weld tests aren't hard at all for anyone who is decent at welding but I just cannot get my beads to come out like I want them to. They always come out grey, I'm guessing its from oxidation? Here are some pics.

http://imageshack.us/photo/my-images/85 ... 134sy.jpg/
http://imageshack.us/photo/my-images/26/imag0135j.jpg/
http://imageshack.us/photo/my-images/254/imag0143e.jpg/
http://imageshack.us/photo/my-images/84 ... 144qo.jpg/

On those practice runs, I was at 90-95 amps. I even tried 125 and tried speeding it up but still came out grey. I'm just laying the wire down and trying to go over it.Not sure what kinda machine I have, I just know its a miller. Same goes for tungsten :-\. I know the tungsten has a red tip though, if that helps any. I'm pretty sure I'm using a 1/8 filler rod. Cup size I believe is an 8. No foot control, just a button trigger on the gun. Sometimes, the beads will come out OK and have some color but I can't figure out what I do/did different than when they come out grey and oxidized. How can I get them to come out with that nice shiny red/brown/yellow color? I've tried different angles/length of tungsten sticking out, I just cannot seem to get past this and I'm getting frustrated.

The tests I'm trying to prepare myself for are butt welds on Stainless Steel (6 inch,12 inch) and T joint. I believe the material is 10gauge, if not its 12.

Ignore the 186 amp setting in that one pic, I use that for tacking
I think I've covered everything, if you guys need any more info/pics, let me know please!

[capozzoli]

The welds are contaminated, looks like not enough shielding gas. Could be several things. The ones that come to mind are not enough or too much shielding gas. Or too much Torch angle. Too long of an arc. Wrong shielding gas.

What kind of gas ya using?

I use pure argon, 75-25 will contaminate the weld.

I run about 15 on the flow meter and I stick the tungsten out about the dia of the electrode. For ten gauge you might want to try 1/16" tungsten. You are using thoriated tungsten. That will work.

Sharpen the point carefully an make it real nice. Then clean it up with some 600 grit sand paper.

When I weld ss I get in real close, the tungsten point is almost touching the puddle. Then dip the rod, dont try laying the wire.

Clean the pieces really well with a SS wire brush too. And make sure you don't come in contact with steel tables or tools. These can contaminate the weld with iron. Even a little can screw up a weld.

[StephanusThie]

Too hot maybe?? Turn down your amps a little bit lower.

[ajlskater1]

Looks like you are welding hot. Your cup size looks correct and as far as a tungsten goes 3/32 tungsten should work fine but you could drop down to a 1/16. I noticed the machine you are welding with has a pulser feature, that is a really nice feature for welding ss and keeping the heat down. An 1/8 filler rod seems kinda big for material like that, might want to try out something like .062 or .045 this might help you keep heat down as well and make sure when you are feeding the rod to never let the tip of the rod leave the gas shielded area, it will make the puddle sluggish cause it puts contaminations in the weld and that cause more heat to build up. Jody has really good videos on here about pulse tig setting on ss and just normal welding ss. Since you are not using a foot petal, setting the machine to 4t and using a upslope and down slope helps a lot. Hope these tips help you out. Good luck hope you pass the test!