7018 is much more fluid than say a 6013, but in some ways is much easier to control. When welding vertical, concentrate on holding the rod on the sides of the butt, and the middle will take care of itself, resulting in a flatter fill. The last pass before capping should be as flat as possible, and filled to just below the surface of the parent metal, the two lines will then act as a guide for your capping run(s). Cap consistency will be much easier to achieve on a flat fill and will also improve with practice. Looking good.