well i am not a pro welder or pro anything. but everytime when my welder did that there was a problem inside. either sheath, wire wheel tension, feed wheel, or dirty tip. i had a hobart handler several years back it was a good machine, a 220 model though. i am running a miller now. still have a big hobart arc welder though.
the good thing about a mig is, if you weld a lot of rusty metal like i do, you can put the wire exactly where you want it in a clean area, then let your hood down and pull the trigger. you don't have to scratch around in the dark like with a arc welder hunting for the clean spot. you might try one of those magnetic grounding clamps. they stick right to the clean area and it doesn't have to be a edge like for a spring jaw type. i also can test my ground with the mig- if i have it grounded good it will make a very small spark with the welder running and i don't have to pull trigger. it's just enough to let me know it's a good connection. it'd very small and short, might look for it. i don't know if yours will or not.
