How could'ya not know why it seems "easier"? Odds are you're relying on TIG's ability to fusion weld - to pool the to separate pieces of metal together w/o filler, "stitching" the puddle with the plasma ball alone. While this is a perfectly acceptable method for nonstructural butt & corner sheet metal welds, the problem is if you're not really careful you'll end up with "lows" - undercut and voids.
Where TIG gets really tricky is manualy feeding the filler rod precisely while maintaining an exacting arc distance with the tungsten - coming in with just the right amount of filler to uniformly "crown" the weld while keeping your pace, rhythm, and spacing with your other hand. Throw in a foot pedal for controlling "heat" through amperage, the need to increase your bead speed due to the metal itself heating up and/or decreasing amperage with that foot pedal - and you find yourself in a complex mutitasking "dance" - while this complexity in fact offers the potential for extremely high quality welds, it's simply not something that can be achieved without lots of practice.
If you TIG "better" than MIG with a $500 machine and "don't know why" - yer doing it wrong and I'd not trust those welds
NOW NOW BOYS , PLAY NICE .
