How to use Buttock and Waterline together in a half-hull model. The Art of Boat Building presents the third part of half-hull modeling. Boat builder, Bob Emser, guides us through making a half-hull directly from boat plan using buttock and waterlines. Using the plans from the Dark Harbor, Bob shows how to adjust the thickness of lifts and add contrasting wood for above and below the designed waterline. As a bonus the attachment of a rudder to the model is covered as well as how to add a rail lift to the deck. Carved of Honduras Mahogany and Bass Wood this beautiful model is one you’ll want to make yourself.