i think you might need to do it again, In my experience that look ametuer mig welded, you need to clean up the steel where you want to weld, sand it for good contact. do the same for where the earthing clamp will be put on. then turn the voltage up to max and slow the wire speed down a bit. try to keep the welding tip close to were your welding for best penetration. tack it first and do a 1/4 of the area at a time, opposite sides first.