The sides of the boat and the bulkheads (the vertical walls inside the boat) are made from 1/4-inch plywood, which is thin and pliable. To stiffen things up, structural framing is required around the perimeters of the fore and aft bulkheads and the transom (the vertical surface of the rear of the boat). But the sides of the boat are arced (narrow at the bow, wide amidships, narrower toward the stern). So that everything will fit properly, the side edges of the framed bulkheads must be cut at angles that will lie flat against the hull sides. Those angles are known as a bevels. Since the bottom drops from the bow and rises again toward the stern, the bottom of the bulkheads and transom must also be beveled.
The bevel angles are detailed on the plans. Where it gets dicey is at the certain corners of the framing, where the cuts must account for both the flared of the hull sides (10 degrees off vertical) as wells as the arc of the hull. I was doing well until I got to the bottom framing for the transom. There, the angles were greater than elsewhere on the boat and the framing is bigger to handle the loads that are placed on these joints. I kept cutting the required last piece using on the table saw to cut compound angles, but it keep coming out wrong. Eventually, I got the angles right, but realized that I was transferring measurements onto the wrong edge of the beveled piece. I had to borrow from my old project scrap pile to make up for the wood I ruined.
All told, I probably have more than 15 hours in this. Builders beware . . . read and re-read page 151 of Michalak’s book before proceeding.