Designing a Balsa Wood Beam: Max Strength, Min Weight

AI Thread Summary
To design a balsa wood beam that maximizes strength while minimizing weight, it's essential to consider factors like dimensions, density, and applied forces. The beam must be 500mm long with 25mm supports on each side, totaling 550mm, and should not exceed 100mm in width or depth. A critical failure point is reached when deflection hits 50mm. A suggested approach is to use a nested architecture, incorporating cross-beams to enhance structural integrity. This method allows for incremental reinforcement, optimizing the beam's performance before construction.
Struggling
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Hi for school i need to design a balsa wood beam. Winner is judged be strength to weight ratio.

i have searched around and found all the stress and strain values for balsa wood at different densitys etc...

now my dilemma is that i have to use formulas to design this beam before it is built. Iam having trouble getting started.

would anyone be able to point me in the right direction? iam a little confused as to were to begin, so much needs to be taken into consideration such as widths,lengths,density, forces etc etc

and how do i find the beam design that will hold the most amount of force?

beam needs to be 500mm long with 25mm supports on either side. total length 550mm

width and depth no more than 100 mm and the beam is said to have failed once deflection reaches 50mm.

please help thanks
 
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Struggling said:
Hi for school i need to design a balsa wood beam. Winner is judged be strength to weight ratio.

i have searched around and found all the stress and strain values for balsa wood at different densitys etc...

now my dilemma is that i have to use formulas to design this beam before it is built. Iam having trouble getting started.

would anyone be able to point me in the right direction? iam a little confused as to were to begin, so much needs to be taken into consideration such as widths,lengths,density, forces etc etc

and how do i find the beam design that will hold the most amount of force?

beam needs to be 500mm long with 25mm supports on either side. total length 550mm

width and depth no more than 100 mm and the beam is said to have failed once deflection reaches 50mm.

please help thanks

Make a beam with a nested architecture: Construct cross-beams to reinforce the length, construct smaller cross-beams which reinforce the smaller cross-beams, make even smaller cross-beams which reinforce the smaller cross-beams. Keep nesting it until you get tired or run into a constraint.
 
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