Eleanor Roosevelt High School 1st Annual Mustang Regatta Winners

1. Eleanor Roosevelt High School 1st Annual Mustang Regatta Winners

2. Eleanor Roosevelt High School 2nd Annual Mustang Regatta Winners

3. Cardboard Boat Materials • Materials NOT Allowed • Wood, Styrofoam • Plastic sheathing • Fiberglass, PVC • Coated cardboard • Silicon, Wax, Tar • Caulking compounds • Metal • Staples, clamps, screws • Glues & Clear tape • Permissible Materials • Corrugated Cardboard • Appliance, Grocery & Any Other Stores • Cardboard “blocks” • Furniture stores • Cardboard Tubes • Carpet/Linoleum stores • Fastening & waterproofing material • Duct or masking tape • Latex House Paint

4. Cardboard Boat Physics • How deep will it sink? It depends on the amount of water you displace Displaced Volume of Water (V) V = L x W x H Boat Displaced Water Water Water Displaced(ft3) = Weight-of-boat-&-people-lbs 62.4 lbs/ft3-H20 Depth(ft) boat sinks = Water Displaced(ft3) Length X Width of boat (ft2) Weight of Water = 62.4 pounds/cubic-foot Example: Box boat, 3 ft X 6 ft, 1ft tall (high) Boat area = 3’ X 6’ = 18 ft2Weight of boat = 30 lbs Weight of 4 people = 600 lbs Water displaced = 630lbs  62.4 lbs/ft3 = 10 ft3Depth it sinks = 10ft3  18 ft2 = 0.56 ft  12 in/ft = 6.7 inches Boat will ride with about 5.3 inches out of the water

5. Cardboard Boat Physics Generally, the wider your boat, the more stable it is. why a boat tips overshapes of hulls and stabilitysecondary stability Center-line Center-line Center-of-gravity Center-of-gravity Center-of-buoyancy Center-of-buoyancy Righting-Arm (Moment) POSITIVE Righting-Arm (Moment) NEGATIVE

6. Cardboard Boat Physics • Boat Buildingtips1Freeware boat designer • Some real designs and discussion SimpleBox Slanted Box V-Shaped Bow Pontoon Design Outrigger Design RaftDesign

7. Cardboard Boat Physics According to Newton’s 1st Law, on object is lazy and will tend to want to keep doing what it is already doing unless a net force acts on it. So you will need a net force to get your boat to start moving and a net force to turn it around. This is difficult because without sturdy paddles it is hard to push and pull water. The gravitational force on a cubic foot of water is 62.4lbs. That is very difficult to push aside because it has a lot of inertia.

8. Cardboard Boat Physics According to Newton’s 2nd Law, an object’s acceleration is directly proportional to the net force acting on it and inversely proportional to it’s mass. This means that if you exert a lot of force it is likely that your boat will accelerate to a higher speed. Likewise, if your boat is less massive, you can exert less force to accelerate it to a greater speed. To find out more about this you can look up Newton’s 2nd Law and kayaking or canoeing. Physics of Kayaking

9. Cardboard Boat Physics According to Newton’s 3rd Law, every force is a single interaction between 2 objects. So, if you want your boat to move forward, you must cause your oar to exert a force on the water, then the water exerts a force back on the oar causing the boat to move forward or sideways. The boat usually moves in the opposite direction to the force you exert. For more information about this look up how to paddle a canoe and the physics of paddling a canoe.physics of paddlinghow to paddle

10. Cardboard Boat Design • Set the Design Goal: Float, Turn, Fast, Looks • Sketch out your design • build a scale model from thin poster board (1in = 1ft) • estimate materials or plan how to use what you have • plan out what construction techniques will be used • 1’x1’x3’ box: will float 187 lbs. • If it’ll hold you, it’s big enough to float • Flat bottoms (sit-to-paddle) – are easiest to make, but can cause tipping problems. • Rudders help keep you straight but adds complexity to your design.

11. Cardboard Boat Design • Short boats (<8’) - are difficult to keep straight • Best Height: 18 inches • allows room to sit/kneel & still paddle over the edge • Best Width: • 18”-30”(max) for 1 person • 48” wide for 2 people side by side • Kneeling is a “power” position but sitting is more comfortable

12. Construction Tips & Techniques • Cover edges of cardboard with cardboard– they act like siphon • Cardboard Tubes make great frames • Cutting for joining & bending • Fastening tubes together • Cardboard Hull • Bottom 2-3 layers, fasten & cover the seams w/cardboard • Sides 2 layers • Decorate with house paint • Reinforce the area where you sit, kneel or stand

13. Construction Tips & Techniques • Duct tape only non-painted surfaces (tubes or frame that will be covered) • Duct tape shrinks when painted • Duct tape can be covered with masking tape if you need to paint it. • Clear tape - it melts when painted and does a horrible job of sealing cardboard. Don’t use it!! • Masking tape for edges & seams, after overlapping with cardboard

14. Steering can be a challenge

15. Look at that power stroke by the Stars & Stripes Winner

16. Why did they sink? Because of poor turning technique & too much buoyancy. They were riding too high in the water, then when they turned they leaned a little bit too far over & started to take in water

17. Disqualified! You cannot use the lane markers to help you pilot the boat!

18. Celebrities sometimes show up, like Peter Pan, Wendy, Tinker Bell, and Captain Hook

19. Boat can have interesting decorations & design

20. Best Decorated Winner!

21. Boat can be small & still seaworthy

22. Boats that do not have several layers of cardboard that are overlapped at the edges and corners can become misshapen & take in water.

23. Showing Mustang Pride, but oops, the oar was not attached firmly enough to the handle and so it became a little bit harder to pilot.

24. Except for edges & corners, insides can be left bare cardboard. (Just don’t get them wet) You can tape the insides, but don’t attach tubes with tape, these fell off in the water

25. The Kraken was a cool looking boat. However, the boat suffered a small separation of the bottom, on an edge not thoroughly attached nor reinforced with extra cardboard. It also took in water, but did not completely sink.

26. This boat nearly sank because the tube edges were not covered with cardboard, instead they sealed them with duct tape. Duct tape is not the perfect seal for a cardboard end. It should have been covered with cardboard, then taped.

27. House paint is an excellent sealant for cardboard, making it very water resistant. However, you cannot paint over duct tape. The paint disintegrates the duct tape glue. You can paint over masking tape. In fact it is made to be painted over. You can paint cardboard first, then assemble boat. You can assemble with duct tape & then cover duct tape with masking tape before you paint.

28. Remember that you do not need to coat the boat with duct tape. Duct tape and masking tape are binding materials, not waterproofing materials. Latex house paint on cardboard or on masking tape over cardboard is a better waterproofing. However, you can never expect paint to take the place of cardboard and tape in construction and binding materials.

29. Be like the Pirate, and have a little fun with this project.