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Tower Design
Introduction

The following information is designed to assist you in building your prototype tower. Read through this entire page before you begin. Make notes on any areas that are not clear and be sure to ask your teacher to explain anything that you do not understand.

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These are the forces that will be acting on your structure.

Consider the process of construction for assembling the tower. Full scale towers are designed to be built in sections with materials that are manufactured to specific size and dimensions. When the final construction is done on site, there is very little tolerance deviations. The fit is so well engineered that it practically falls together. It must be stressed that care be taken when you build your prototype. The fit of each piece must be precise in order to have a much stronger tower when finished.

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Arches and Triangles help to evenly distribute the force

No matter how well a tower is designed, if assembled poorly, it will perform poorly. Towers are built to be symmetric and the joints must have precise mitering for tight surface to surface fits. If the joints show gaps between the wood surfaces, the final structure will be very weak and fail quickly at these joints. Winning designs rarely fracture at the joints. Incidentally, glues work best when surfaces being adhered are flush. Do not depend on the glue to hold when used as a gap filler. In addition, this excess use of glue will always add excess weight to the whole structure, defeating the project by being both overweight and weak!

           

Consider the process of construction for assembling the tower. Full scale towers are designed to be built in sections with materials that are manufactured to specific size and dimensions. When the final construction is done on site, there is very little tolerance deviations. The fit is so well engineered that it practically falls together. It must be stressed that care be taken when you build your prototype. The fit of each piece must be precise in order to have a much stronger tower when finished.

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Cross bracing can help prevent shearing

Tips of tower Construction

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Gluing up one side of the tower

  1. Start by drawing the legs to fit the outside dimensions of the testing stand.
  2. Carefully draw in the cross members such that they form triangles or trusses to connect the two legs together.
  3. Tape your drawing to your work board and cover with wax paper. It is most important that your structure be built in a consistent manner.
  4. Number each cross member in its assembly sequence and use the first to replicate three more.
  5. If your design uses butt joints, leave the first side in place once it is built.
  6. Let dry 12 hours before proceeding to final assembly.

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Gluing and clamping sides together

Contest Rules

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Contest Rules

1. Materials

  • Only the materials provided (wood and glue) may be used in the tower structure.

 2. Construction

  • The top of the tower must support a load block that is 2" X 2".
  • minimum height = 10.5 "
  • maximum height = 11 "
  • No laminations are allowed.

 3. Testing

  • Place the tower on to the scale and measure the mass of the tower in grams.
  • Center the tower on the stress analyzer such that the rod connecting the loading block can pass through the center of the tower and hook onto the threaded rod.
  • Take Digital Photograph of Tower Design
  • Record a digital movie of testing the tower in the structural stress analyzer.

 4. Scoring

A tower’s structural efficiency will be determined by this equation:

Structural Efficiency = Maximum load mass of the tower

The Tower with the highest structural efficiency will be the winner.