Tig weld aluminum, Green band Tungsten or Red?

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Hello,I am somewhat new to tig welding, I recently bought a new Miller Syncrowave 200. I had welded some with a tig welder with one when I was younger, mostly welding steel. The traditional way I was taught that red band was generally for ferrous metals and green band for non-ferrous. Green band has no thorium in it. Now I'm told that withthe new power supplies you are to use red band for steel and aluminum. WhenI started, the training was that the thorium in the red band would contaminate the weld in aluminum as it was released from the electrode during the weld process.This info was given to me by many, including a rep for Miller. When I went to buy red at the welding supply store for welding aluminum the sales guy laughed at me a told me how stupid I was. I explained my understanding and he laughed harder telling me he has been in the industry 100 years and I have no idea what I am talking about.So…….. any feed back would be appreciated. If this is the case, do you ball the red just like you do the green for AC aluminum welding? In addition, is it still OK to use green for aluminum? Any insight is greatly appreciated, this has caused me great confusion
Reply:I'll just address the use of Red (2% thoriated) for aluminum.I was taught in the welding program at the College of San Mateo to use 2% thoriated with AC for welding aluminum back in  1978.  The instructor was very knowledable in the aerospace and  aircraft welding of aluminum done in the San Francisco Bay Area,  I remeber him telling us how the a overloaded tungsten, at too high a current, could spit tungsten into the weld and subsequently the weld would fail radiography.With the older transformer power supplies of the day, before inverters, he showed how to sharpen and then ball the tungsten on a small block of copper or brass, using DCEP, then switch to AC to weld.  The 2% thoriated ball will tend to develop a split or fissure in it,  which can make the arc wander and reduce control of the puddle.  When this happens, you stop and remelt the ball the with DCEP, to get rid of the fissure.Since 2% thoriated handles higher current than pure, and provides easier arc starting, there is no reason to use pure that I know of.
Reply:If 100 guys answer you, you'll get 100 different answers. And since most weldors are blue collar rednecks, none of them will change whatever they believe, ever.I have a Sync 250, it will weld alum with any color I put in it. I have had pretty good luck with red because, if I hold my tongue just right, it gets a nice tiny ball. However, I am using green in class because that's what they have (also on a Sync 250).For alum, I grind any Tu to a crayon tip, including the flat end; and start welding. It will ball itself from there. No matter what color I use, the arc dances around for a second before it stabilizes.Inverters will run any color except green on alum.Don't tell the weld shop what you're thinking, just ask for the color or type Tu that you decide on.Since I prefer to sharpen both ends of my Tu, idealistically (sp?) I only want one color in the garage.The Sync 200 is a good choice.Edit: Pulser beat me. About the pure (green), I use it because I have it; but I won't be buying anymore.  At my level it doesn't matter. Last edited by Craig in Denver; 04-13-2009 at 02:37 PM.9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:1/8 pure (green) tungsten will get you to about 170 amps before the ball is beyond the width of the tungsten, at that point is when I would assume you are throwing tungsten into your weld puddle.I have used both red and green. I have not encountered a scenario where I needed more than 170 amps, but it will happen I guess.I agree with Craig in denver, dont tell that dipstick at the supply store what you intend to do unless he asks. Just tell him pure, or thoriated. Some of those guys dont know jack, and some are worth listening to, but how do you tell?You go to welding web and ask your question since no one here is trying to sell you something.
Reply:i have used red 2% for 18 yrs and dont have any probs and like said dont tell them ask for what you want  pay and leave
Reply:I think I tried all colors on AC.  Cerated (orange) balls real easy.  I have balled 1/8" when the AC wave balance was more than 50% + at 150 amps.  Red works fine, but does split on occasion.  Gold works great for me on every thing, so does red....or black.  If you want what green I have left, pay the shipping I only have inverters but have used red on a transformer machine.  I think the green worked better on an old 300/300.All I have are inverters.DavidLast edited by David R; 04-13-2009 at 04:37 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:wow!!  I wish this would of come up a few years ago.  I going to try red on some alum. and say by to green.  this will make life easy.  More time to make stuff and less time changeing tu.Daye
Reply:see below posted--(I sand a slight flat or 45 degree/side cone on the very end)http://weldingweb.com/vbb/showthread.php?t=23430This is with a 3 phase inverter, which allows one to go really unbalanced on AC, more thanthe single phase machines.               Why do that?1-This focuses the arc, constricts it-significantly--allowing the heat to be highly concentrated on one small spot--with the .125 electrode--about .093 dia. In turn, this focused heat-beam, really speeds up aluminum welding.2-Another BIG benefit of the above is the ability to create a stiff arc that lets one get into the bottom of a fillet weld--without the dancing around you see with green. Most helpful on aluminum, again reducing arc-on time significantly.For max heat--unbalanced running 20 CPS/AC, this arc is stiff and the hottest, but not as stiff on 150 CPS/AC--which isn't as hot; but for most heavier stock in aluminum, I just go for the max. heat on 20 CPS/AC frequency--and nail it.(Most, if not-all of the above is highly contrary to the ways of old school welders with oldtransformer machines.)Blackbird
Reply:I asked the same question myself not long ago.  The guy at the welding store told me they ship the new syncrowaves with ceriated tungsten and that it is suitable for both dc and ac work.  So I bought some for my older syncro 250 and it works fine.  No need to ball the tungsten, it can handle a lot more current than pure tungsten (green).  Lanthanated works fine with a point on aluminum in a square wave machine that had balance control.  Sounds like green is for old school sine wave machines where you needed to form a ball to handle all that heat at the electrode.
Reply:wow, so really great info you guys, i have been looking to find a good forum that has so much experience. The text books are great, but real experience is where it is at. I have always thought that welding is an art and a science.This really helped me out, also made me realize that there is many ways to go about welding aluminum. Thanks for the info on not balling the tungsten, i am going to give that a try.
Reply:Good advice fellas!Don't let that iron in your lungs, turn to lead in your @$$!!!!