Building a Model Motorboat

Introduction

Man has used boats for thousands of years. They have been used for fighting, trading, exploring, fishing and as a means of transport across rivers and oceans. Each boat design has evolved over eons of time until it has become the best suited for the task required of it.  

Different boats have different purposes.  Some boats for example are designed to travel quickly, some are made to be very stable in the water and others are intended to carry large and heavy loads.  Some are built for fun and others are meant for work. 

The Challenge

Your task for this unit of Design Technology is to investigate, plan, and create a working model motorboat which will suit a purpose you have chosen.  When your boat is finished you will evaluate it and the process you went through to achieve it.  You will keep a Project Journal of the process you go through and  you will add to your journal regularly.  Before you go much further with this project you must begin your project journal. Before your next class you must have a small notebook to use as your IDT Project Journal. You will also need to create a new folder called IDT in your student account on NAS01 - You can create this folder now.

INVESTIGATE

Do some research on the internet on boats.  Look at modern boats and examine some history by looking at boats that have been used by man over the ages.  Save anything you find interesting into your DT folder, web pages, text, photographs, diagrams, design ideas. Look at a variety of hull types, mono-hulls, catamarans and other multi-hulled vessels, flat bottom boats, boats with keels.

Investigation Task 1:
Click here and save this file to your IDT folder.  After it is saved, open the file and complete the activity. 

The next step in this challenge is to decide on the expected use of your boat.  It is this use of your boat which will determine the style of your design.  For example if you want to design a boat to carry a very heavy load it will look and perform quite differently from a racing boat built for speed.  Collect information, text and graphics and save them into your DT folder, you will need these for your designs and your journal.

Here's a link to get you started:

The Mother of All Maritime Links  

Here are some examples of different motor boat Ideas.

A classic Motorcruiser	A Houseboat
A Patrol Boat	A Chinese Cargo Boat
A small river boat	A Fishing Boat
A Racing Speedboat	A Canal boat
A simple launch boat
A Pontoon boat	A simple Motorboat

One of the first decisions you will have make is what type of hull will your boat have.

Basic Hull Designs

The boat hull is the part of the boat which is underwater.  Hulls are either displacement hulls or planing hulls. A displacement hull moves through the water, while a planing hull is designed to skim on top of the water and can travel at a much higher speed. Each design has its limitations and advantages.

A displacement hull requires very little power to move through the water. Large trawler yachts, fishing boats and large sailboats are displacement hull boats. They can easily move through the water with small, economical engines or sail power. They ride very comfortably even in rough seas, but cannot go very fast.

As you increase speed, a planing hull rides up on top of the water allowing the boat to travel at much higher speeds. Unless the water surface is flat or nearly so, a boat with a planing hull must be properly designed to prevent pounding with each wave. Planing hulls require considerably more power for their size and are therefore generally limited to fairly small craft.

Examples of the most common hull designs are flat bottom, deep vee, round bottom and  multi-hull.

For more information on hull design click here

Investigation Task 2  For an example of this activity click here

PLAN

Next, you must design a boat to meet the purpose you have chosen.  Your designs must show the appearance of your boat from both above and the sides. 

Click for some examples - Example 1 - Example 2

You must also include the expected measurements of the various design elements in your vessel.  Remember the more detail you put into your design, the easier it will be when you come to building your boat.  Your boat will be built from an A3 sized piece of polystyrene board, so your design must fit onto a single sheet of A3 paper.  As part of the design process, you will test your design by building a paper version of your boat prior to making the real version.  If you find there are production problems during this design test you will have to re-design your boat and test again.

Some Professional Boat Designs

CREATE

You will be doing your practical work in the Gr. 6 Home Rooms.  The hull of your boat will be constructed from a polystyrene board with a paper cover A3 size (29.7cm x 40cm). You may choose from a variety of other clean, water resistant materials in the construction of the superstructure of your boat, such a plastic, balsa wood, cork or polystyrene.

Special care must be taken with the joining of the various parts, PVC glue and/or water resistant tapes may be used. 

You must check with Mr. Adams before commencing the construction of your craft.

The propulsion method will be via a battery powered submarine electric motor with a propeller and adjustable rudder, made by the Tamiya company.

A tub or sink of water can be made available for some minor testing of ideas in the class room.

The main testing of your boat will be in the school swimming pool on two different days. The time between the first and final testing is to give you time to make any adjustments or improvements that may be necessary before the final demonstration.

PLEASE NOTE: The environment must be respected, so no dirty or water soluble materials can be used which may pollute the pool. Great care must be taken in the construction of your boat so that no parts will fall off and sink. Before boats can be placed in the pool for testing, they must be scrutinised. When you have satisfied the scrutineers, you may test your boat in the pool.

The final Boat Demonstration will be in the school swimming pool.  We will invite some important people to this demonstration, such as Mr Searle and Mr. Underwood.  Please think about who else you would like to invite to this important event and tell Mr. Adams who you want to come.