I would set the Amp,s higher than recommended by the manufacturer for the thickness then use the pedal to control the heat.
Hotter first then very little when finishing. I always end with an extra dime on top to prevent the crater you can get at the end.
Keep using proper tig filler rods and make sure they are clean too. Can wipe them with Scotch Brite and clean rag. Try to keep the filler rod near enough the welding arc to not melt but still get shielding gas coverage in between dabs.
Should have better luck with your larger tungsten...
The ball on the tungsten is fine and some prefer it.
Aluminum can corroded kind of like Swiss cheese where the surface looks clean and then dark soot appears after you arc it. Keep cleaning, dirty aluminum doesn't weld easy.
Try the same gauge but new material because welding holes in...
Not sure if you're practicing with old/corroded aluminum but it would be best to start with new/clean. When you hit corrosion with the arc dark soot appears and it needs cleaned again, each time.
Do you have mig or spool gun experience?
What did you set the gas flow at?
Easy, just remove everything that holds it down and used it for the pattern. 5052 .100" if memory serves. Original was probably. 062". Also it's over 4' wide so had to find larger sheet.
I prefer the no feedback helm units. Also not impressed with the xtreme systems number of turns from lock to lock. The cable has very little free play but docking can give your arms a work out.
Look for a helm with the newer quick connect where the cable attaches.
