After you’ve picked the boat design you are going to build, one of the first steps will be lofting the dimensions of the boat into full size patterns. Depending on the size of your boat, lofting itself may not be the first step, as you have to have adequate room to loft onto your medium in full scale. Since our boat is relatively small, we were able to loft our dimensions onto a roll of paper as it was big enough to encompass even the largest frame.
Since this was the first time Sam and I had built a boat, we spent some time studying and reviewing the plans to ensure we knew what we were doing. Once we thought we were ready, we grabbed our roll of paper, some pencils and markers, as well as a straight edge so we could connect our measurement points into lines that would dictate the overall dimensions of each frame of the boat.
There are two crucial reference lines that are used to ensure all measurements relate to the same points namely the baseline and the centerline. These lines help while lofting and each measurement from the plans is applied to the full size paper as referenced from the baseline and the centerline. The centerline is like a mirror, and each side of frame on either side the centerline should be symmetrical. Measurements from the baseline govern the height of each frame.
Lofting actually begins when you transfer the measurements from a plan or drawing onto your paper, creating the full size frame dimensions right before your eyes. The plans we used made this process easy; just pick a frame number, mark the required measurement points (height and width), then connect the points with a straight edge. Once connected, you are left with the actual dimensions of the frames which will come in handy when cutting them from your lumber as part of the next build step.
After each frame is drawn out, take some time with a ruler or measuring tape to ensure your dimensions are uniform and equal on both sides of the centerline and from the baseline. Carefully make notes on your full sized dimensions, noting the frame number for each set of lines, and any other notes necessary per the builders plans.
Upon the completion of lofting, it’s time to actually start the build. Next, the frames will need to be built per the full size lofting plans that were just created.