If you go mig.
DO NOT USE A CLARKE SHITE WELDER
90% of your problem could be your setup, clarke welders suck donkey I know because I made the mistake of buying one of their mig welders, total and utter dog shit
Changed to a Sealey Mig and have no problems in 15 years
One other thing to watch out for is extension leads, if you really HAVE to use one make sure it is a proper heavy duty job or you will end up with bird shit welding

Mark