Frosty tig weld

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Why is it that my welds on aluminum are frosty. My welder is a Lincoln Precision 185, setting are ac, auto balance 120 amp max. I normally use pulse setting.I am welding 6061-T6 1/4 and 1/8th inch thick, I am just running beads as a practice session. gas is set at 18-20 argon 3/32 tungsten have tried 2% ceriated and thoriated with a #6 gas lens. Filler rod is ER5356 1/16ththe beads are clean no black, (other when the al jumps on the tungsten) just are frosty I have not learned to stack yet so they kinda flow like what you would see on steel. Anyway can someone sort me outLast edited by Rolland; 08-17-2011 at 12:25 AM.
Reply:Try real quick setting the wave balance to the 3 o'clock position (like 75% EN or so). Sometimes too much EP (cleaning) will etch the dimes after they've been layed down. Also when your work gets too hot it will lose it's shine. And of course make sure the metal is reasonably clean.Welding/Fab Pics: www.UtahWeld.com
Reply:Rolland,Several things come to mind.First off, you're likely running too cold.  If the test material has any mass to it, 120 amps is not enough.  Crank up the amps to about 150 to get the puddle started and then back off with the remote as heat builds in the material.The 185 does not have the amps to weld 1/4" aluminum without preheat or the use of a gas mix (helium added).Most times a "frosty" bead comes from inadequate travel speed.  You're overheating the puddle (because you don't have enough amps/heat to establish a quick puddle).Aluminum likes to be welded hot and fast.  Too slow, you cook your puddle and your filler.You'll find it easier to move up to 3/32" filler.  For a new guy, with aluminum, it's hard to keep 1/16" in the covering gas without melting the filler before you get it to the puddle.Turn your pulser OFF.  You don't need it on aluminum.  You want all the heat you can get out of the welder.Between the ceriated and the thoriated tungsten, ceriated is your better choice.  On a transformer machine the thoriated has more likelihood of forming small balls around the tip and dropping off in the puddle.  For those use to using a balled tungsten, I'd recommend zirconiated.   Forms a ball but takes the heat better than a pure tungsten.Again, try cranking the amps up and move faster.  Control the puddle width with the remote (amp control).Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:thanks for the responses I will work on those suggestions.
Reply:Sundownlll-MikegyverThanks for the help I readjusted my wave balance and turned up the heat some and things are looking much better. also had to speed up a little. Still have not mastered the stack of dimes look but the welds to look much better and  no more frost.
Reply:Remember also, with aluminum you have to push the wire in to the puddle. Just dabbing won't give your the dimes that you are after. When you look at aluminum beads that have been created using GTAW, you'll notice that the 'dimes' are rounded and bulbous, this is created by pushing the filler in to the puddle. For long beads you'll have to feed the wire through your hand as well as in to the puddle.Thats how I learned anyway.Good luck,Marc Leonard
Reply:Originally Posted by fronty_78Remember also, with aluminum you have to push the wire in to the puddle. Just dabbing won't give your the dimes that you are after. When you look at aluminum beads that have been created using GTAW, you'll notice that the 'dimes' are rounded and bulbous, this is created by pushing the filler in to the puddle. For long beads you'll have to feed the wire through your hand as well as in to the puddle.Thats how I learned anyway.Good luck,Marc Leonard