Gas flow, dirty nozzle, worn tip, old liner, are all things to check. Also dirty material can cause some of the same. Even different steel from different manF can have different impurities in the mill scale can be troublesome.
generally if it is pushing through the arc and popping like a machine gun, too much wire speed
if it is burning the wire back towards the tip, balling up, and falling out in big globs, not enough wire speed.
Some millers are inherently bad due to their hot start and inductance characteristics that can’t be changed until you go pretty high up in the model line.
I had a lot of trouble with:
once I set wire speed to make a nice long 7-12” weld, it would start and burn back to the tip
if I changed the wire speed to fix the start issue, then I had too much wire speed to complete the weld the way I desired.
The ultimate solution for me,
I sold the miller and got a Lincoln that I can adjust the run in wire speed and inductance. This let me fine tune the parameter to exactly how I wanted them, vs having to change my welding technique based of what machine or position at the time.
