TIG welding ally questions........

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Got some questions for tig welding ally.1.  I am new to TIG welding.2.  Using 2.4mm RED tip 2% thoriated tungsten3.  No.6 alumina nozzle  (have bought a no.7 gas cup to try)Question 1.Electrode extension.  I have been running it at about 1/4" to 3/8" outside the nozzle.Went and spoke to a guy who does ally welding, have known him for about 5 years and he has always had the tungsten (same one and size) either flush or slightly back in the nozzle.   He also uses a gas lens, but can not remember why he change over to it instead of a standard nozzle.Question 2.Arc length.  I watched him tig weld and as the tip of the tungsten was flush with the nozzle the arc would have been maybe 3/8" o 1/2" i guess.   And along he went just dabbing and dabbing the filler in and it worked perfect.Everything I have been seeing online favors the short arc where the tip of the tungsten is just off the weld bead.  This is how I have been trying.    I had a go at it as well, and what do you know I could do it too.  So what arc length are you supposed to use?Amperage and pedalHe uses no pedal and just sets the machine to 95 amps, we both did welds on 1/8" thick ally (3mm).  Outside corner weld.  Beautiful.MachineAt work we have a green machine (won't mention the name) but it is 200 amps.  Inverter has AC balance and frequency adjust.He has a Fronius " Magic Wave 2200"  Which from the little bit I used just nailed the welds perfect.We tried to fiddle with the balance on his machine just to see what it would do to the The machine I use at work the AC balance adjustment you notice a lot.  He never changes the balance, did not even know what it was for.  His machine it set to 0 and you can go either way -5 or +5.  We tried -2.5 and +2.5 it did make a difference but now way near as much as the machine I use.  I also wonder what is frequency is as our you can have slow or fast.  I don't even think his you could change.   We looked at all the buttons but could not work it out.Anyway the point is his just seems to work very simply and basically.  All he does for thicker or thinner materials is just increase or decrease the amps, that's it.Things to note:a)  He had a very noticeable dabbing of the filler rod action.  When I had a go he told me to retract the filler rod further away.  It was maybe 1 to 1.5" in and out each time.  But this confuses me as I read that you need to keep the tip of the filler rod inside the envelope of the gas.  If you don't the tip of the filler rod can oxidize and get dirty, contaminate the weld etc etc. Maybe as he has a gas lens and I only have a standard nozzle he is able to retract the filler rod further away????b)  Another thing related to this above dipping the rod statement was I think I had noticed that the tip of my rod would melt off not from the main focus of the arc but maybe I held the rod too close and it melted off but not under the arc.It just struck me as "wrong" that his tungsten was flush to the nozzle and the arc was very long and wide.  But maybe that is how it's gotta be.  I mean it works for him, and his welds **** all over mine so far.What about shiny welds?What causes or lets you make shiny welds in ally?Example I had two bits of 3mm sheet (1/8") and sandwiched them together.  Then fused the two edges into one.  The result was a shiny reflective aluminum weld bead.  See the photo.Yet when I did this on an outside corner same settings and everything, the edges melted in but they were not shiny like the previous weld.  I wonder why this is.  Also this weld I could see some tiny bubbles coming up, and even now the finished weld has tiny pin holes along most of it.  My thoughts are lack of gas  coverage????  In a previous post I asked about stainless tig welds that were not shiny and reflective.  The answer was the gas was not sitting there for long enough after it was welded.I wonder if this same thing is true for aluminum as well? Attached Images
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Reply:I stick my tungsten out of the cup, but if I'm just welding on the bench, it's usually not that much. Maybe 1 to 1.5 times the diameter of the electrode. I keep my arc length very short, just long enough so the puddle doesn't grow into the electrode. In my opinion, you can actually get away with a longer arc on aluminum versus steel. Again, with the filler, I only pull it out enough to stop it from melting when it's not directly in puddle. If you are having trouble with that, you might need to step up a filler size. Shiny welds on aluminum come from proper heat and the type of material. 4043 filler, when used properly, leaves a very shiny bead. If you overheat it, though, it will turn hazy and grainy. 5356 produces more of the dulled bead, but very smooth (not grainy). Additionally, 3000 series aluminum like diamond plate welds beautifully. Why is there such a large gap on your outside corner joint? Butt the plates up so that back inside edges are touching, and you are left with a square trough that is the same height and width as your material. Then fill that. It will roll over smoothly and take much less filler and give you a nice bead profile instead of being sunk in and under-filled.