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Homework Help: Balsa Wood Tower

  1. Feb 11, 2007 #1
    I was assigned to build a structure out of balsa wood (1/8 X 1/8 inch) and glue. It has to be between 7.5 and 8.5 inches high , cannot have mass greater than12 grams, and has to be able support at least 60 pounds (this would only get me about a C) while withstanding torque.

    I've been researching online and i found Euler's Buckling Theorem, but I can't really figure out how to apply it to the design. I have not been able to find much other information and I honestly have no idea what I should do. Most of my classmates just seem to be building whatever comes to their minds first, as my teacher has not really told us how to approach the problem.

    Any ideas?
  2. jcsd
  3. Feb 11, 2007 #2

    D H

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    This looks like Odyssey of the Mind (or some teacher who liked what they saw in this competition). Hint: Don't build a balsa house.

    What is the most stable geometrical shape?

    Which would be more likely to break under pressure: a single long piece of balsa, or a pair of half-length pieces connected end-to-end to equal the length of the single long piece?

    Edited to add:

    Odyssey of the Mind continues! This is such a cool left-brain/right-brain competition. Their home page is http://www.odysseyofthemind.com" [Broken]
    Problem 4: Out Of The Box Balsa
    The team's problem is to design, build, and test a structure made of balsa wood and glue that will balance and support weights. The team is allowed to use materials other than balsa wood and glue to assemble the parts of the structure. The structure will be designed to fit completely inside a box that is smaller than the assembled structure. When competition time begins, the team will remove the parts and assembly materials from the box, creatively assemble its structure, and test it by placing weights onto it.

    I judged this category many years ago. The winning entry supported over 400 pounds. This is a left-right brain competition. Boring engineering alone doesn't win the day. They spun a play involving DaVinci, time travel, and their invention while exposing their structure and then piling weight on it.
    Last edited by a moderator: May 2, 2017
  4. Feb 12, 2007 #3
    I'm sorry, I went to the website and I'm still at a loss as to what how I should design my tower. Do you have any ideas about what kind of shapes to use as cross sections and what kind of joints to use to connect peices of wood? thanks
  5. Dec 4, 2008 #4
    I have the same problem. I have to build a tower out of 18 feet of balsa wood. But I only have to make it hold 15 pounds. I would like to make it stronger than that though. I was thinking of making the inside of it inter lock like those little square magnetix toys my little brother has, but having about 9 of them to make the tower even stronger (each one would be turned differently like ... the 1st one being turned differently than the 2nd but the same as the 3rd so on). Or make the inside kind of like a wooden gate with cross beams. Im just trying to find out if these are reasonable ideas or not. (I also heard that someones balsa wood tower held about 320 pounds!!!)
    Any ideas ...
    Thank you
    Last edited: Dec 4, 2008
  6. May 16, 2011 #5
    Ok I am in 8th grade and i made a tower holding 543 pounds before exploding.
    1. Use double beam if possible(that is to glue 2 beams together for main support.
    2. Use no less than four main rods, if more(that was our contest limit) put more.
    3. Put the beams close together. The closer they are the stronger it is.
    Those are the rules that got me first place.
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