Students will build a balsa wood tower and test how much weight it can hold. They will learn basic engineering principles like tension, compression, and structural shapes. They will be provided 4800mm of balsa wood and design their tower within this limitation. Towers will be tested and awards given to the tower that holds the most weight and has the highest efficiency rating based on materials used and weight held.

1. How to build your tower

2. Objectives 1. Learn basic engineering principles 2. Identify basic shapes that form structures 3. Design a tower for structural strength 4. Design and construct balsa wood tower using limited material amounts 5. Calculate efficiency rating to determine best designed tower. You will design and build a balsa wood tower. The tower will be tested to see how much weight the tower will hold. http://cfbstaff.cfbisd.edu/scrudderr/Tower/towers.htm

3. What is a tower?? An exceptionally tall building or part of a building or an exceptionally tall structure used for some functional purpose. In the past, towers were usually used to house bells (bell towers), for observation (watch towers) or for signaling (light houses). Perhaps the earliest record of a tower comes from the Bible where the story of the tower of Babel is told. Other notable towers include the Tower of Pisa and Eiffel Tower, two completely different types of towers. Today there are many more types of towers which are used for a wide variety of functions. A few examples are transmission line towers, radar towers, radio and TV broadcasting towers, even towers for suspension bridges.

4. BASIC ENGINEERING PRINCIPLES AND DEFINITIONS TENSION: the action of being stretched to stiffness COMPRESSION: the action of being pressed or squeezed WEIGHT: a load with a certain heaviness, a specific force due to gravity SUPPORT: to hold up or serve as a foundation TENSILE STRENGTH: the greatest stress a substance can bear without tearing apart

5. BASIC STRUCTURAL SHAPES TRIANGLES - rigidity of the triangular shape can support weight securely SQUARES - can support weight, but can twist and collapse if not supported POLYGONS - like squares, can support some weight, but will twist and collapse if not supported.

6. Step 1: Draw 10 Thumbnails

7. Step 2: Draw, measure and figure out how much wood you will need to build your tower.

8. Don’t forget… Your tower has to be at least 200 mm tall (it can be taller than 200 mm but not shorter) THE TOTAL AMOUNT OF WOOD YOU WILL RECEIVE: 4800 mm

9. Step 3: Make two copies and cut the original and the two copies out.

10. Step 4: Tape your copies to the cardboard using scotch tape. Then write your first and last name and the class period. Finally, using masking tape, tape on the wax paper. Make sure the wax paper is as flat as possible.

11. Step 5: Get your wood and begin cutting, pinning and gluing.

12. DIFFERENT TYPES OF JOINTS Miter joint Lap joint Notch joint Butt joint

13. Correct Way To Pin Wrong Way To Pin

14. This is the CORRECT way to glue your tower together.

15. This is NOT the correct way to glue your tower together. You will earn a lunch detention if you waste glue.

16. Step 6: Take the sides off the wax paper.

17. Step 7: Take twisty ties and tie each side of your tower together and then glue the sides.

18. Step 8: Put your name on your tower.

19. Step 9: It is time to test to your tower!

20. TWO AWARDS 1. MOST WEIGHT HELD 2. MOST EFFICIENT

23. OBJECTIVES: 1. Learn basic engineering principles 2. Identify basic shapes that form structures 3. Design a tower for structural strength 4. Design and construct balsa wood tower using limited material amounts 5. Calculate efficiency rating to determine best designed towerStudents will design and build a balsa wood tower. The tower will be tested to see how much weight the tower will hold. The student then figures out the efficiency rating for their tower. RESOURCES: www.trebuchet. com INTRODUCTION If you look up the definition of a tower, you will find the following; "An exceptionally tall building or part of a building or an exceptionally tall structure used for some functional purpose. In the past, towers were usually used to house bells (bell towers), for observation (watch towers) or for signaling (light houses).Perhaps the earliest record of a tower comes from the bible where the story of the tower of Babel is told. Other notable towers include the Tower of Pisa and Eiffel Tower, two completely different types of towers. Today there are many more types of towers which are used for a wide variety of functions. A few examples are transmission line towers, radar towers, radio and TV broadcasting towers, even towers for suspension bridges.BASIC ENGINEERING PRINCIPLES AND DEFINITIONSTension: the action of being stretched to stiffnessCompression: the action of being pressed or squeezedWeight: a load with a certain heaviness, a specific force due to gravitySupport: to hold up or serve as a foundationTensile Strength: the greatest stress a substance can bear without tearing apartBASIC STRUCTURAL SHAPEStriangles - rigidity of the triangular shape can support weight securelysquares - can support weight, but can twist and collapse if not supportedpolygons - like squares, can support some weight, but will twist and collapse if not supported. http://cfbstaff.cfbisd.edu/scrudderr/Tower/towers.htm