Tig arc problem

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Trying to get tig rig set up I am using a Maxstar 140.I am trying to weld new SS boat railing, but this happens on all metal.Acetone cleaned. Solar Flux inside.I am welding indoors with no draft.When I start the arc it seems to be fine, after a couple of seconds a bright arc ball forms right at the tip of the tungsten for a second or two (no set time), then it goes back to normal. This is even before a puddle is even formed. Just holding the arc in one place and it pulses from bright to normal every two or three seconds. The more amps I push the brighter the ball gets but still pulses off and on. When welding and it does this bright to normal thing, you can not see the puddle. If helmet is adjusted for the bright time, it is too dark to see when it quits. If adjusted for normal my eyes adjust to the bright light and when it goes back to normal I cant see, by the time my eyes adjust it goes bright again. Welds come out blue to gray looking. Tungsten has black deposit.I have gone from nearly 0 cfh to blasting out. If I put about 30 cfh of argon through it will slow down but not quit. 80cf bottles go quick.I have gone through 3 bottles of argon trying to find out what is wrong. Tried following:Leak test gas hose. No leaks, holds pressureNew regulator and flowmeterNew torch with valve.Screen type gas lens, #6 cupUsing:Miller Maxstar 140Gas connected with 1/8 vinyl hose from flowmeter to den connector with hose adapter.techweld 150 amp torch with valve1/16 2% torated tungstenHelp any ideas.Glen
Reply:Sounds like you got the polarity backwards.  TIG is generally DCEN, meaning the torch should be hooked to the negative terminal.Check that out and try it again, then get back to us.  Better yet if that doesnt cure it take a picture of the tungsten after you try to weld.Have we all gone mad?
Reply:Thanks for the response.I tried that.The polarity is right.If I have it reversed the tungsten will ball up.The ball I am talking about in the post is a bright electrical ball of arc light, just below the tungsten point.GlenLast edited by Redrunner; 02-07-2011 at 10:12 PM.Reason: add
Reply:Oh, I thought what you were describing was the tungsten balling up.  If thats not the case then I cant really picture what you are describing.  If you could get a picture of the weld and tungsten it should help.It sounds like you worked out every possibiity of a gas issue, so now its making sure the machine is set right and the power is going where it needs to go.Last edited by sn0border88; 02-07-2011 at 10:13 PM.Have we all gone mad?
Reply:Sounds like a helmet problem to me . . . if it happens on all metals.  Try a fixed shade lens to see of the arc really alternates between bright and dim (less bright).  Check your battery.JimDynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:I will try a fixed lens helmet, but I am confused on which lens to use. If I set my auto lens to between 9 and 10 it is fine for when there is no bright arc flash.If i set it to between 12 and 13 it is good for the bright time but too dark to see when the arc flash goes away.Maybe the helmet is defective, it does not automatically go from a light shade of dark to darker shade  once welding is started. Like say from 9 to 13.I will try my fixed lens.Glen
Reply:Originally Posted by RedrunnerI will try a fixed lens helmet, but I am confused on which lens to use. If I set my auto lens to between 9 and 10 it is fine for when there is no bright arc flash.If i set it to between 12 and 13 it is good for the bright time but too dark to see when the arc flash goes away.Glen
Reply:I tried a fixed helmet lens today and it is still flashing. If I have it set on 10 it is perfect, until that little bright electrical ball of light forms just under the tungsten point. Then it blinds me for a few seconds, and when it goes back to regular  my eyes take time to get adjusted, and just about that time then it flashes again. Cant S%* Sx&#.I have noticed one thing on the .065 SS tubing I am working with, or any other metal. If I have a really big puddle, say 1/4" round, and stuff rod into it, it does not happen as often, but it still flashes. It's when I move the arc to the metal that is not quite melted yet, then it flares up bright. I do not want that big of a melted base metal bead though. It seems to destroys the the SS properties, and starts rusting. I have cleaned the metal to no end,dedicated SS brushes, acetone, grinding, and it still happens. I do not want to get the base metal so red hot. It seems to destroys the the SS properties, and starts rusting. One thing I have not checked is the electrical. Tomorrow I will try on land power electrical current, compared to the marina power I have here.Glen
Reply:You really need pictures of the completed welds and tungsten, as I think most on here are having a very hard time grasping what you are describing.Have we all gone mad?
Reply:OK, I'll get some photos posted.I need to get another argon tommorow in Houston. It may be Thursday before I can get them up. Thanks sn0border88,Glen
Reply:How does the tungsten look after a weld or two? Is it still sharp and silver?Your Maxstar140, is it a st or stl. Does it have a built in gas flow solenoid? If so, the problem may be there. Also, the Maxstar lead connectors are known for poor, sporadic contact, resulting in drastic arc fluctuations and poor arc start. I remedied this problem after advice on this forum. Stuffing small bits of tin foil in the lead receptacles on machine panel allows the twist connectors to tighten.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:It is the 140 STL. No solinoid though. I have the argon connected at a special den connector that has a tubing fitting made into it. Gas then runs through the lead hose to the tig gun. I shut it of and on with a valve knob on the gun. "Unstable arc" that describes the problem, and I do get sticking tungsten alot of the time, but not all, with the lift arc function. I've never cleaned the connections. I have a 3/8 copper fitting brush that might fit right in. I'll clean the connections and try the foil spacer.The tungsten varies. Sometimes it will stay sharp for quite awhile, but eventually the point will dull, get a white scale 1/4" from the tip, and turn black above that. This may be due to dipping the tungsten. It's hard to keep 1/16" off the metal when you can't see.GlenLast edited by Redrunner; 02-09-2011 at 08:59 AM.Reason: add