Consider the fillet in the soap dish model. If the top surface were undersized for some reason, or the fillet radius did not reach to the top surface, an extend operation could resolve the problem. In this case, select Construct tab > Surfaces panel > From 1 Surface > Extend.
Unless you are sure of your process, it's safer to create a new surface instead of modify an existing surface. Select the Create new surface option and name it. Working through column and row options and previewing the results, the intended surface is achieved using First Column and an extension of 0.1 inch.
