Balsa Bridges
Designing your bridge
- Complete Bridge building questions. Use Model Bridges packet to answer questions.
- Turn questions in. 1 per group. Make sure ALL group member names are on it.
- See Truss Designs pdf in Google Classroom.
- Sketch ideas. There should be blank paper on the front counter.
- Get together with group and each group member should sketch 3 top, 3 bottom, & 3 side bridge designs.
- Choose 1 top, bottom, & side design, and then see me. (Consider how much wood will be used you don’t want to run out. You are limited to 30 feet of wood)
- Test side design on West Point Bridge Designer. (Set deck elevation to 12 meters.)
- When you have a working side, Save it.
- We will transfer to ½ size sheet of graph paper. I will go over this step in class.
- Use a ruler to transfer printout to graph paper. You will need to get this paper from the teacher.
- Bring the finished ½ sheet to your teacher to check your work.
Building your bridge
- If your drawing is approved, you will transfer it to the full size sheet. (11’ x 17”)
- Draw the side design on a sheet of 11” x 17” graph paper; use a ruler. The bottom of the side must be 12” long.
- Draw the top and bottom designs on a separate sheet of 11” x 17” graph paper. Use a ruler. The bridge bottom MUST BE 12” LONG AND 3” WIDE. The top design MUST BE 3” WIDE and as long as the top of your side design.
- After drawing the designs have them checked by your teacher.
- Mount the drawings to cardboard, cover the 2 -11” x 17” drawings with waxed paper.
- Get building supplies from cart, see your teacher to receive the 30’ of wood.