Lofting – Lofting is a drafting technique whereby curved lines are generated, to be used in plans for streamlined objects such as aircraft and boats. The lines may be drawn on wood and the wood then cut for advanced woodworking.
What did you do?
Over the past few weeks at the Independence Seaport Museum, myself along with two partners were able to conduct lofting techniques to design a wooden duck boat. We began by constructing the main gridlines on a white wooden board. This sets up the profile (side) view and plan (birds-eye) view for the lofting lines. Starting with the Baseline and the Centerline, we measured in the y axis lines in intervals of on the baseline by using a guide packet with all the dimensions necessary. We then drew in 90° vertical lines by using triangulation to make right angles along the Baseline. We then drew the x axis intervals at different increments based on the guide packets dimensions, completing the grid. We also got to draw in the transom line and the main sheer line on the profile view. As well as getting to work on a body plan view, drawing the front view and rear-view lofting lines of the boat.
What did you contribute to the project as a whole?
These techniques are necessary to create the contour lines and understand how to shape the boat. The scale is one inch to one foot, by scaling up the measurements, all the pieces will have exact proportions when they are being used to dimension the boat. By using the different views, we can interpret the shape of the boat accurately and know what the contour and size of the boat will be. Using the lofting view gives us a good understanding of how the contour of the boat will be set up, and what curvature the hull will need at every part. This ensures that the boat is built to the right specifications. Once we have scaled the dimensions properly, we can use the lofting lines to design and cut assemble the 12 ft duck boat project.
What challenges did you face and how did you overcome them?
The challenges my group faced were during the interpreting the measurements packet and drawing the loft lines. When we were putting the points in place for the transom line and our first lofting lines, we had trouble understanding how to read the grid and decipher where the points go. We were able to get a better understanding with this challenge by consulting our instructors and going over the plans multiple times to find where we were getting confused. Our other challenge came when hammering picks and trying to bend the wood to match the points we had measured and laid out. We could not get the curves to meet the points positions initially so we had to start over and rework the wood to match the points. In doing so, the line was smoother and touched each of the lines but still not as exactly as we had hoped.
What did you learn?
During this process, I learned the how to construct gridlines based off a baseline and centerline to design a plan view, profile view, and body plan for lofting lines. I was also able to understand how to interpret water lines, buttock lines, and measurement lines laid out in the guide packet and find points accordingly. Using this I could plot and draw lofting lines using picks and curved wood bar techniques I also became accustomed with. All of this put together to create a solid understanding of what lofting is and how it applies to the boat building process.
