The outline cut is the most crucial aspect to the way your board looks and any dips or wobbles in the outline will show up in the rail and you can't get it out at that point.For a flawless outline we make a tool called the Rail Runner that does the work for you. It also shapes the bottom tuck of the rail which is one of the most critical aspects of a board since it determines how much "grip" into the wave the board will have so it's best to undershape it to start and screen it to the radius you want. As soon as you cut that tuck railband a little too much the foam is gone and you're intended rail shape is altered.