Milk Carton Derby

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1. Pick your Category
You have a choice between speed or style. Speed boats compete for trophies while style boats compete for major prizes such as cash or vacation packages.
The category you pick will determine what your boat will look like. Some categories require your boat to have a theme.

2. Create Your Design
Once you have chosen your category, study the rules and regulations.
Your boat must rely completely on milk cartons for floatation, however, above the water line anything goes. Speed boats are usually long and narrow, like a canoe, while style boats are all shapes and creatively designed to win prizes.

Plan to build your boat by drawing it out, knowing dimensions and approximate weight when finished. Crew members make up most of the weight on a boat so prepare ahead of time by collecting milk cartons. Speed boats usually have one to four people while style boats can carry more than a dozen depending on size. For every 100 pounds on the boat you will need 50 half-gallon milk cartons.

The design of the boat is up to you but keep in mind that there are things that could affect the outcome of the race. A boat that is too narrow for the weight on it will capsize. If your boat leans from one side to the other, it will go slower, therefore try widening the boat.

To propel the boats many will paddle them with oars. It is possible to use side wheels or propellers as long as they are moved by human power. When turning the boat, a rudder is usually not needed. However, long and narrow boats may have a problems turning unless there is a long clear patch of lake.

ALL CREW MEMBERS MUST WEAR A COAST GUARD-APPROVED LIFE JACKET WHILE OPERATING ON THE WATER.

3. Gather Your Materials
Hulls can be built of wood, plastic or steel. The superstructures can be built of pretty much anything that you can think of. Be creative with your boat by decorating it and making it look nice with paint, crafts, etc. You can use glue, nails, tape and other normal construction materials.

Finding milk cartons is usually the biggest challenge. Ask those around you to help you collect. Other places to find milk cartons would include coffee stands, restaurants, hospitals, schools and cafeterias. Just ask for their “empties.” You can also ask the Seafair office if they have any cartons available by calling 206.728.0123 or info@seafair.com after April 25.

4. Construction Techniques
Hulls should be joined together with nails, screws or even welding if steel is used. Steel tie-down brackets can provide extra strength. Use wooden 2x4s for main structures and smaller cuts for areas that will not be holding heavy weight.

To keep milk cartons shut, use hot glue and reinforce the seal by stapling the mouths closed. Then hot glue the cartons together bundles. Wrap the cartons in duct tape to reinforce. Use staples, tacks or hot glue to connect the cartons to the hull. To prevent cartons from breaking away, you may use steel or chicken mesh on the bottom of the boat. DO NOT enclose the cartons completely within the hull, they must be visible. If they are not, it will result in a disqualification.

You can choose to build your boat as a single unit or pieces that can be assembled at the lake. Bring all materials needed with you and allow adequate time for construction.

5. The All-Important Test Run
Many milk carton boat builders will neglect to test their boat with a trial run. Most of the boats that sink on derby day are those who were not tested before hand. When testing your boat, look for flooding in milk cartons, breaks, cracks, stability in water, and how it handles in the water. Do a test run with enough time to fix anything that may arise on race day.

6. Registration, Inspection and Operation
To pre-register, use the form provided in the online brochure (available in May). If you do not pre-register, visit the Seafair registration table at Green Lake as soon as you’re ready to put your boat in the water. An inspector will examine your boat to see that it complies with all the rules and regulations. He/she will assign you to the appropriate category and give you a registration number to put on your boat.

7. Launch Your Boat!
Pay attention to the day's Schedule of Events and listen to the public announcements to find out when it is your turn to race or parade with your boat.

For more information, contact Seafair.