A clean, well-prepared tungsten of good quality is absolutely essential to the proper performance of your TIG set-up.
With inverter machines in both AC and DC polarities, your 2% Ceriated or 2% Lanthanated electrode should be ground to a point with an included angle between 15 and 30 degrees, then the tip blunted slightly. If the tip is left as a fine point, there will be a much higher likelihood of tungsten inclusions, as the point can melt off into the weld pool.
Always grind your electrode along the axis, never perpendicular to the axis. When the grind marks go around the tip instead of along it, the arc will be more likely to wander as it tries to follow those minute grooves. Be sure to use a grinding wheel — preferably diamond and never aluminum oxide — dedicated to tungsten sharpening to avoid cross contamination from other metals.
If your electrode is dipped into the weld pool, never grind through the contamination because it may get loaded onto the wheel and deposited right back onto your electrode whenever you rework it. Also, never break off a contaminated tip. Instead, it should be cleanly cut off with an abrasive wheel to prevent the small cracks that result from fracturing. These cracks can wreak havoc on the electrode’s performance.
Taking care of the small details can have a significant effect on your welding success!