The Miller 250 is running!!!

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So I'm up and running with the Miller 250.  What a great machine.  I have done some aluminum and steel.  With thicker aluminum have done okay welding it without rod. Questions...... With thinner Aluminum I'm having allot of trouble.  I can't seem to get control of a local spot of pooled metal.  The arc seems to jump around and burn the metal.  What should I start playing with to get control of it?  Is it just a matter that with the lower amperage that I don't have the finesse to hold the tip at the right distance consistently?  I do have a good point on the tip.I tried using an aluminum filler rod but it would just melt and blow away in a blob off the work.  Why would it not want to bond? Could the gas be blowing it away?  I'll have to get back to you on what rod it is but it looked like a common aluminum alloy and was the most abundant in the stack of filler rods I got.Fingers to hot!  My fingers get really hot really quick.  I'm wearing dishwashing gloves.  Should I get something else?  O.k. just kidding I'm wearing regular leather work gloves.  Do welding gloves insulate better or am I doing something wrong with hand position.  Petal resolution feels funny.  I haven't tiged for over 15 years but I do remember having nicer control of amperage with the pedal before.  This one seems to be very course almost feels like I have only low, middle, and high, as if there are three settings.  I imagine I am doing something with my settings that is doing this.  Any ideas on what to  mess with?  Or is this a symptom of something worn out in the pedal? I assume there is a pot in there somewhere.  Dirt between wiper and coil???Thanks guys you rock!!!
Reply:Ok, I'll try to offer some suggestions. First, what thickness, and what amperage? Is it on ac? Did you clean the metal? What chemically enhanced tungsten are you using? ( thoriated, lanthanated etc. ) I am just now a new tigger myself, and I think that I can help with the puddle issue and filler melting problem ( I think ). I Have experience those problems in class that I'm in. Aluminum isn't like steel; it doesn't change color, or " puddle up" the same.  what you will be looking for is a shiny area. It is unlike steel in that it won't look like the metal is molten, and you will have to kinda create your puddle with the filler being pushed into that shiny spot, to get it going. You are having the problem with melting filler, because you might have the torch tipped too far back ( pointed toward the direction of travel too much ), with your filler rod right there taking the heat; you might also be holding the filler metal too close to the torch while you're waiting to use it, or your too slow adding it. Once you add the first bit of filler to get the puddle going, you've got to go and not sit there, and it is also important to pull back the filler rod fairly quick to keep it cool. I'm not sure what the pedal problem is, but can guarantee the other guys here can help. Good luck with it.Daryle.
Reply:No expert here either, but I do a fair bit of Al.  I like to use 2% ceriated, approx. 1 amp per .001" of material and clean, clean, clean, then clean some more.  Al forms an oxide almost immediately, this oxide has a melting point about 3x that of the actual Al and it will cause you fits if you don't clean it adequately.  Your problems with the filler and the puddle are caused by the same thing: torch position and control.  Daryle is right, too much travel angle is causing that big blob of useless Al oxide on your filler and your big puddle and hot hands are from having your tungsten too far from the joint.  Get your grinder ready because you are going to dip you tung alot for awhile.  You have to get closer.  I can't really think of anything for your pedal-feel issue, make sure you don't have your amps up too high, I start with about 5 more amps than I think I'll need and usually end up turning it down.  You might also check your balance.  I think newer syncro's default to 60% when you switch it to AC with the tig button pushed, but check it anyway.  Just thought of something else for your filler contamination problem, if your travel angle and heat are good, try turning your gas down, too much flow can cause turbulence which will bring oxygen into the weld area.Stay tuned, there are a lot of golden-arms around here who will help you out.
Reply:Great! Thanks guys.  I will play with all those variables and get back to you with an update.Take Care,Adam