Everlast 200A TIG welder: welding aluminum

Here's the parameters for AC TIG welding aluminum (about 1/8" thick 6061):

Torch setup:
1/16" ceriated tungsten electrode
#6 gas cup
3/16" of electrode stickout
electrode is ground into a sharp point

Gas:
pure argon at about 7 lpm or 15 cfh (The Chinese regulator reads out in lpm, not cfh !)

Welder:
No pulse
75% electrode negative balance
5 s post-gas
Zero arc force
Max amperage of about 100A

Rod:
4043 1/16" or 3/32"

In order to strike the arc, I usually have to push the pedal pretty far down, sometimes all the way. Having a really clean, sharply-ground electrode, and a really clean metal surface will make striking an arc a lot easier.


Here's some points that I learned from my first few hours playing with the machine:

Arc force: This control is only useful for stick welding, not TIG. I searched the internet for a long time trying to figure out what this control actually does. Here's the best explanation:
http://www.millerwelds.com/education/articles/article108.html This "arc force" control is also called "dig" and describes how forcibly the stick welding arc can push material away. A high arc force setting will boost the arc current when the machine senses the arc voltage is dropping too low (meaning a short-circuit is about to happen). This boosted current blasts away base metal and rod, preventing the stick from welding itself to the base metal. Anyway, I had no idea about this control for the first few sessions that I used the TIG welder, and left it all the way up (50A). I noticed that it made striking the arc much easier. On thick materials, this was not a problem, but on thin stuff, I would blow through the material upon striking the arc. The arc force control is supposed to be enabled only for stick welding, but that is not the case on this machine (super200P). During TIG welding, I assume the voltage is low enough to cause the arc force control to set a "minimum" amperage of 50A, which is why it was a big problem for thin material. For TIG welding, be sure the arc force control is turned all the way down!

AC balance: This machine has a strangely configured balance control. The range is %20 to %80 electrode positive. It's unusual to indicate the electrode positive percentage, and anything over %50 positive is considered not useful at all. I am sure there are crazy situations that require it, but the electrode melts so easily, and the base metal has such a huge etched area at those levels, I can't see it ever being that useful for common operations. So, never set the balance past %50 even though the machine's range makes it seem like it might be a useful thing to do. In fact, having a minimum of %20 electrode positive is still quite a lot. It would be nice if the machine went down to %5 or %10.

Gas flow: The Chinese flow meter is calibrated in liters per minute, not cubic feet per hour. Watch those units! lpm is approximately half of cfh.

Electrodes: No one uses pure tungsten anymore. The information on the web is old, and repeated by people who have never used modern electrodes or modern welders. You can weld all common metals with a ceriated electrode ground to a fine tip. The tip will round-over a little bit during AC welding, but there is no point in "balling" the tip of the electrode. All it does, is make the arc difficult to control.

Pulse feature: I have tried it a few times, but I haven't noticed any big difference in welding ease or speed. I'll try it later, and write more about it.

Finger-tip control: After using the welder for a while with the pedal, I switched to the plasma cutter, and hooked up the finger-tip control switch. It didn't plasma cut. The machine would not strike an arc at all. After futzing for a long time, I hooked up the pedal control (even for plasma cutter), and it started to cut like a dream. I tried the same for the stick welder setting, and it too, required the pedal to be connected in order to weld. It seems the finger-tip control circuit in the welder either died, or never worked properly. Hmmm. I'll bet this has to do with the "background" "max" and "arc force" settings.