got a dig dial?
if your using a machine with a dig control dial use it! high for 6010, low for 7018. it will fine tune your arc to the point that putting a root pass in pipe,up or down, will be automatic and your fill/cap will lay out smooth and stack easy. just go from high to low as you progress from in to out. it helped me immensely, i didnt have a bust in over 7 years.