On thing I see that isn't mentioned here... Any self shielding fluxed rod/wire needs to have a clean base to work well... That is after making a tackweld... Chip and brush to clean it well, for the final pass... Then again after the welding is done, to inspect the final results..
Kinda drives me a bit nuts to see it(I'm a little OCD about it when I'm using mine) not cleaned up a bit, and people say hey see my kart/buggy/ machine... But all these fluxed-up welds not clean...
I agree for the most part. But guys who use a 110v HF flux core machine don't have to worry much about chipping and wire brushing. They just need a good grinder. Hahaha, hehehe.