6013 isnt the rod size mate, thats the number to tell you its a mild steel rod, perfect for what your doing, some rough amp settings, 2.5mm rod=90 amps 3.2=120 amps, 4.0=150, shouldnt need any bigger rods for the anything small, if your welding positional ie vertical drop your amps by 20-30, keep practising on scrap, get your arc distance right and travel speed, youl know when your getting better, also clean any surface your going to weld, ie rust, grease, paint, any other questions just stick them up,