- 1). Read up on the basic principles of model bridge designing before trying your hand at it (see Resources). It's important to get the basics down before building a model.
- 2). Decide on the type of model bridge to build. Popular types include Pratt, Warren, Arch and Howe. If you'd like to exercise your creativity, use model bridge designing software to build a model bridge of your own design (see Resources). Be aware that each bridge design may have its own weight and distance constraints.
- 3). Scale your bridge and outline it on grid paper. Use the straight lines and right angles on the grid paper to plan out your bridge according to the scale and skewer lengths. Write down measurements clearly.
- 4). Build your bridge with skewers by meticulously following the design on the paper. Use string, wood glue or other connective objects to join the skewers. Use a glue formulated for wood, like Elmer's Wood Glue, to have the skewers form a solid connection. Create "gusset plates" around the connections using small bits of wood to reduce stress on joints and ensure a strong connection.
- 5). Examine your model bridge's functionality. Run an appropriately scaled and weighted object across the bridge. If the model bridge almost collapses in certain parts, remove the item and make modifications by disconnecting the skewers and rebuilding as necessary.
- 6). Practice your model bridge building until you become confident enough to enter contests.
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