By Matt Assenmacher
As summer approaches, keeping students interested in learning while wrapping up the school year can be a challenging task. I teach mechanical engineering at Hartland high school in Hartland, Michigan. My students learn the principals of technical design while guiding through a fun, hands-on, year-end design project.
Each spring, the students design and build lightweight boats out of a 4′ x 8′ sheet of lauan plywood. Before construction, the students must successfully design and build a scale prototype of a boat out of balsa wood. Through this process the students discover the limitations of the design based on the materials that are used. It also helps them understand how all of the pieces work together to create the entire boat.
The students are then divided into groups of three. Each group is given a sheet of lauan that they will use to create the patterns for the sides, gussets, and transom of the boat. The groups use a jigsaw to cut out the patterns, then drilled and zip-tie the sections together to form the general shape of the boat. The gussets are then installed along with side rails in order to improve the overall strength and shape of the boat.
To make the boat watertight, all edges are sealed with West System 105 Epoxy Resin mixed with 206 Slow Hardener and applied to 2″ fiberglass tape. The epoxy is cured overnight. The next day, students turn their boats over and fill the inside seams with a combination of resin, hardener and 404 High-Density filler. Once again, the epoxy must be cured overnight. The following day the students patch and complete any overlooked areas.
The boats are then ready to set sail at the test site, a shallow creek behind Hartland High School. Students launch their boats to test whether they’ll float. This year the students successfully floated 25 boats on the creek. Students, teachers, and other school employees typically come out to watch this fun event. All of the boats travel up the creek (about ¼ mile away) to a second dock where the students can then pull their boat out of water.
I have been been doing this project for the past five years. I inherited the idea from a former Hartland teacher and mentor, John Naughton, who had done this project with his students since 2002.
There are many types of boat building projects for the classroom setting. Some plans call for alternative materials, such as cardboard, plastic or other wood laminates. The West System products ensure that the boats are sealed in order to allow the boats to float properly. It is a fun project for the students and a great way to end the school year.