Our joy after the boat successfully completed the sail
Designing the boat's structure and preparing wood sticks
Building the base
Securing the wooden frame and wrapping the boat with paper
Coating the boat with red paint and using more masking tape to seal the boat
The boat with an estimated waterline
Successfully completed the testing in a swimming pool
After testing, all wood sticks are intact except 1 at the side breaks (which doesn't affect the stability of the boat and can be fixed by gluing). Only a small water come inside after the test, which shows that the sealing is successful. Hence this boat can still hold one person (with his/her weight up to about 68kg) in the water for several more trials. It's important to know that the person inside the boat can face difficulties when trying to get off from the boat without making too much water flowing inside nor making the boat breaks.
Experience:
1. I-beam and vertical wood beams are beneficial to place at the bottom.
2. Don't make the boat too high, otherwise there would be no enough woods for securing the bottom from collapsing.
3. Since the sailor will lean forward, the center of mass is at about 3/5 of the total distance from the front, but the greatest pressure is exerted at the location of a person's lower body (not legs).
4. For the boat project, 1 whole roll of paper-based masking tape is used. Masking tape is a great tool for sealing holes (even after painting); multiple layers of tape can be used to seal the front corner, in which is easily to have a hole. Hence, having spare paper-based tape is extremely useful, even before and after the testing. It's essential to prevent water from flowing inside the boat; otherwise the water can increase the weight and sink the boat.
5. Be aware on using oil-based paint; it won't come off when it is dropped on any surface without using special chemical solutions.
6. Since the material is limited, the team should first determine a bare-bone structure (the boat requires many fixed-length wood sticks that can't be shorter or longer); the team need to prepare every fixed-length first before preparing sticks without a firm length.
7. The oil paint would take roughly 12 hours to dry, and the wood glue would even take about a whole day to dry.
8. Having glues that secure wood joints is needed first before wrapping the paper and then coating with paints.
9. When sailing, do not shake or lean back and forth (in both horizontal and vertical direction); this reason has caused a number of boats to collapse and sink.
10. Again, since the material is limited, do not throw away any extra woods, even the stick is tiny; there is always a place to use scrap woods to strengthen the boat (like shaping a triangular shape wood and placing it in a corner).
2. Don't make the boat too high, otherwise there would be no enough woods for securing the bottom from collapsing.
3. Since the sailor will lean forward, the center of mass is at about 3/5 of the total distance from the front, but the greatest pressure is exerted at the location of a person's lower body (not legs).
4. For the boat project, 1 whole roll of paper-based masking tape is used. Masking tape is a great tool for sealing holes (even after painting); multiple layers of tape can be used to seal the front corner, in which is easily to have a hole. Hence, having spare paper-based tape is extremely useful, even before and after the testing. It's essential to prevent water from flowing inside the boat; otherwise the water can increase the weight and sink the boat.
5. Be aware on using oil-based paint; it won't come off when it is dropped on any surface without using special chemical solutions.
6. Since the material is limited, the team should first determine a bare-bone structure (the boat requires many fixed-length wood sticks that can't be shorter or longer); the team need to prepare every fixed-length first before preparing sticks without a firm length.
7. The oil paint would take roughly 12 hours to dry, and the wood glue would even take about a whole day to dry.
8. Having glues that secure wood joints is needed first before wrapping the paper and then coating with paints.
9. When sailing, do not shake or lean back and forth (in both horizontal and vertical direction); this reason has caused a number of boats to collapse and sink.
10. Again, since the material is limited, do not throw away any extra woods, even the stick is tiny; there is always a place to use scrap woods to strengthen the boat (like shaping a triangular shape wood and placing it in a corner).
A small amount of wood glues are used on the wood sticks to repair the inherent wood cracks (they were present before the team received wood sticks) without strengthening it.
Rubrics:
The purpose of this project is to assemble a single or double-person a boat with a limited amount of simple materials. The boat is not powered by a motor, only self-propelled by those who choose to be in the boat on the day of testing.
Students are given a set amount of wood (10 strips, 8 ft x ½ in x ¼ in strips of plywood) to assemble the frame, paper (40 sq. feet, 28’ x 1.5’ sheet) to cover the structure, and paint (non-water soluble paints such as acrylic and spray paint) for decoration and waterproofing. Students are required to gather adhesives/glue (Elmer’s Wood Glue or Liquid Nails recommended, NO fiberglass adhesives or epoxy) and joint clamps for their boat.
The Constraints:
1. Glue must be applied at the wood joints only. No coating the strips with glue.
2. No nails, staples, screws, string or other kind of fasteners may be used.
3. No resin may be used as a waterproofing coating.
4. The design of the boat must be boat-like with sides that lead to a flat bottom or edge. Rafts, surf boards, pontoons, or any design that the navigator might lay down does not qualify.
1. Glue must be applied at the wood joints only. No coating the strips with glue.
2. No nails, staples, screws, string or other kind of fasteners may be used.
3. No resin may be used as a waterproofing coating.
4. The design of the boat must be boat-like with sides that lead to a flat bottom or edge. Rafts, surf boards, pontoons, or any design that the navigator might lay down does not qualify.
The Rules:
1. All materials must be completely dry in order to qualify for entry into the pool.
2. The waterline must be clearly visible and may not be more than 1.0 inch thick.
3. Your boat must have a theme. Any skits that accompany the boat crossing must be no longer than 1.5 minutes.
4. Your boat must be hand-propelled; no oars, sails, motors, etc.
5. Skits, music, slogans painted on boats, etc. must all be approved by the instructor at least two days before boat testing day.
1. All materials must be completely dry in order to qualify for entry into the pool.
2. The waterline must be clearly visible and may not be more than 1.0 inch thick.
3. Your boat must have a theme. Any skits that accompany the boat crossing must be no longer than 1.5 minutes.
4. Your boat must be hand-propelled; no oars, sails, motors, etc.
5. Skits, music, slogans painted on boats, etc. must all be approved by the instructor at least two days before boat testing day.
Texts of the project description, rule, constrain are taken from the syllabus of boat project in my (H) Engineering class.
