Boomilever B/C

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Re: Boomilever B/C

Postby baker » September 25th, 2018, 12:48 pm

Can someone explain the 'projection of 40 - 45 cm' thing... Does that mean the center line of the loading block must be anywhere between 40 and 45 cm? Is that the same for both B and C?

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Re: Boomilever B/C

Postby retired1 » September 25th, 2018, 2:03 pm

yes and yes.

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Re: Boomilever B/C

Postby waffletree » September 25th, 2018, 2:30 pm

Where do you guys acquire your wood? I have considered purchasing balsa online yet I doubt it's quality...
If you need a large amount of cheap wood fast, amazon would work but when you need to make really high quality boomilevers, specialized balsa is definitely a good choice
although the shipping price is kinda annoying if buying balsa online :(
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Re: Boomilever B/C

Postby MadCow2357 » September 26th, 2018, 3:20 pm

I'm going to be ordering wood very soon, but I'm not quite sure how heavy I want the pieces. Last year, I went with 0.9g and 1.2g 36" sticks (0.3g and 0.4g 12" sticks) for towers, and I still have some left, except I assume that boomilevers may require wood of higher buckling strength. Any ideas on how heavy I should get my balsa, or do you guys I should try out what I have right now...
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Re: Boomilever B/C

Postby waffletree » September 26th, 2018, 3:30 pm

I'm going to be ordering wood very soon, but I'm not quite sure how heavy I want the pieces. Last year, I went with 0.9g and 1.2g 36" sticks (0.3g and 0.4g 12" sticks) for towers, and I still have some left, except I assume that boomilevers may require wood of higher buckling strength. Any ideas on how heavy I should get my balsa, or do you guys I should try out what I have right now...
Well if you're getting wood from specialized balsa, i worked with medium balsa for my towers last year. It's strong, but not to the point where it's super duper heavy, and it's still more dense than the weird squishy kind. If you need stronger wood, heavy might do but it seems a bit unnecessary and it's just extra weight. I tried some light balsa but it's a little too squishy and kinda hard to work with and probably won't be strong enough for a boomilever
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Re: Boomilever B/C

Postby dholdgreve » September 27th, 2018, 3:39 am

Depending on how much you are buying, National Balsa offers free shipping on Orders over $150.
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Re: Boomilever B/C

Postby waffletree » September 27th, 2018, 3:31 pm

Hmm...yea, I think National Balsa would be a great place to buy lots of wood to get you started, but once it gets to competition season, i prefer using more 'accurate' wood that has limitations on how dense the wood is.
It'd be great if i could find a way to get balsa whose density can be specified when buying online, with cheaper shipping so i don't have to buy so much at once.
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Re: Boomilever B/C

Postby TheRealToast » September 27th, 2018, 4:20 pm

Is purchasing balsa wood worth it?
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Re: Boomilever B/C

Postby dholdgreve » September 28th, 2018, 2:54 am

Is purchasing balsa wood worth it?
As opposed to growing your own?... yes.
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Re: Boomilever B/C

Postby kinghong1970 » September 28th, 2018, 5:06 am

Is purchasing balsa wood worth it?
As opposed to growing your own?... yes.
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Re: Boomilever B/C

Postby waffletree » September 28th, 2018, 9:26 am

Is purchasing balsa wood worth it?
well yea unless you plan on using plywood or popsicle sticks or something
like for these type of building events balsa is by far the best choice to do the best you possibly can
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Re: Boomilever B/C

Postby DarthBuilder » October 10th, 2018, 5:36 am

In the rules it says that the loading block must be between 40-45 cm. Does this mean the actually loading block or the center of the block where the chain comes down?
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Re: Boomilever B/C

Postby Carrot » October 10th, 2018, 6:13 am

In the rules it says that the loading block must be between 40-45 cm. Does this mean the actually loading block or the center of the block where the chain comes down?
The center of the loading block.

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Re: Boomilever B/C

Postby Cow481 » October 10th, 2018, 10:08 am

How would you figure out the length of the tension pieces. The window of length would seem very tight. If you make it to short, the boomilever would sit at a downward angle from the loading block angle and if it was to long, the boomilever would also sit at an upward angle from the loading block.
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Re: Boomilever B/C

Postby retired1 » October 10th, 2018, 11:23 am

Answer to the question would be to use math. My preference would be to make a scale drawing and measure it.If the tension members are from the hook to the load eye bolt, then I think you have it reversed. But,if you have the angle of attachment to the main portion, then it will always be at a level orientation. The height above the do not exceed line will vary.

Not a problem if you accurately graph it. I like the large quad paper from office depot.

Actually, I put it in my "Model Smart 3 D" computer program and it does all of that for me as well as accurately predict the results for what ever densities I entered into it.


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