Need help building a boomilever for my physics class?

[lt337]

I have to build a boomilever for my physics I class. I am not, nor have I ever been an expert architect. I have no clue as to how these are supposed to work and I need a good website to get tips for building. It has to be at least 40 cm long and only 15 cm high. We can use one bolt to connect it to the board. It needs to hold 12 kg of sand.

 

[PeterO]

I have to build a boomilever for my physics I class. I am not, nor have I ever been an expert architect. I have no clue as to how these are supposed to work and I need a good website to get tips for building. It has to be at least 40 cm long and only 15 cm high. We can use one bolt to connect it to the board. It needs to hold 12 kg of sand.

A google search is a good start.

I found this

http://www.youtube.com/watch?v=B_MNP65dNH4&NR=1&feature=endscreen

but there was other stuff on google.

 

[lt337]

I have tried 4 different designs, none of which have worked. The most I have gotten it to hold is 18 lbs. Is there any way to make the compression part stronger without adding too much weight? The one with the highest efficiency gets the best grade, so I wouldn't want it to be too heavy. We have been using balsa and bass. Any ideas to help support?

 

[MacLaddy]

I need a good website to get tips for building. It has to be at least 40 cm long and only 15 cm high.

I can't imagine a website with these dimensions. What kind of monitor do you have?

 

[PeterO]

I have tried 4 different designs, none of which have worked. The most I have gotten it to hold is 18 lbs. Is there any way to make the compression part stronger without adding too much weight? The one with the highest efficiency gets the best grade, so I wouldn't want it to be too heavy. We have been using balsa and bass. Any ideas to help support?

failure under compression is usually associated with distortion of the member that fails. The shorter the member the less it should flex, so it seems you want to have your triangulation more compact.

You might have a section that looks like a rectangle with one diagonal - making two triangles as we like to do.

While you could insert the other diagonal as well, you might add two shorter struts perpendicular to the existing diagonal, going to the other two vertices?

 

[CWatters]

Perhaps see "compression" here..

http://scioly.org/wiki/index.php/Aia's_Boomilever_Guide