TIG thin AL

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I'm trying to TIG ~0.03" AL.  Not sure exactly what type it is; all I can say is that it's harder than 3003 since I can cut it on the CNC router.  Came in roll to wall enclosed trailer.  The joint is lap.  I'm not very experienced TIGing AL; I was hoping to just make some tacks.  I'm building a venting hood; picture a funnel.The arc is very unstable (mostly on start); ~75amp AC - 15CFM Arg - 1/16" EWLa-1.5 balled.  The puddle/bead is too wide (~3/16-1/4") and easily tend to burn through and cut the top lap of the joint.  I test the welder on thicker AL and it's working correctly (I assume; I can make a decent bead).Is 1/16" EWLa-1.5 too big and of the appropriate type?  Should I go down to 0.04" or even smaller?  Should I use the same filler diameter than the electrode?  According to the TIG handbook (Miller), ERZr-1 would be best...?Any advice would be greatly appreciate.  Thanks in advance.USINUM - CNC routing workshopPaco's area - blogspot---Lincoln MIGpack180 (GMAW - FCAW)Miller Syncrowave 250
Reply:you can do it with 1/16, but try dropping your amps down some.   Also if you can adjust the ac balance turn it more towards the + side so you will get less penetration.Do you have a pulser?  This would be a great time to use it.Have we all gone mad?
Reply:Zirconiated and 1.5% lanthanated behave pretty similarly with AC, the lanthanated perhaps balling a little less. 0.030" aluminium... 75A is way hotter than needed (ballpark for 0.065"), 35-40A more like it. Personally i'd use a 1/16" tungsten, smaller will work but the tip will probably end up a similar size as there's less material to deal with the heat. Biasing the AC balance to more EP will give the tungsten a harder time and if anything result in a wider puddle