Boomilever B/C

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Re: Boomilever B/C

Post by LoneMonkey »

Since the compression beams will have to be "diagonal", how will the loading block fit on top of this? I'm new to Boomilever, but it seems that in the past, people made the outside edges of their compression pieces exactly 5cm and put their tension pieces around that.

Would making it in one diagonal and one straight part, then gluing them together work? (Similar to towers in '18). Or would that break too easily?
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Re: Boomilever B/C

Post by sciolyperson1 »

LoneMonkey wrote: Sat Oct 12, 2019 8:48 am Since the compression beams will have to be "diagonal", how will the loading block fit on top of this? I'm new to Boomilever, but it seems that in the past, people made the outside edges of their compression pieces exactly 5cm and put their tension pieces around that.

Would making it in one diagonal and one straight part, then gluing them together work? (Similar to towers in '18). Or would that break too easily?
It wouldn't break to easily as long as the connection is built correctly, make sure to gusset the connection and add an extra horizontal bracing or two as well.
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Re: Boomilever B/C

Post by Lorant »

So what is the deal with Euler's Critical Load? Can it be used as a valid prediction for the deflection pattern of a horizontal compression member. I am specifically referring to the modes of buckling of a column shown here

https://upload.wikimedia.org/wikipedia/ ... Length.png

Even more specifically, the second column from the left.
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Re: Boomilever B/C

Post by bernard »

Several diagrams for Boomilever have been posted to the national website.
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Re: Boomilever B/C

Post by scioly2345 »

Anyone have any suggestions when it comes to cross piece sizes?
Since the breaks of my recent boomis where just compression, I’m thinking of going from square 1/16 to possibly 1/8 by 1/16 or 3/16 by 1/16 cross pieces in the compression piece.
I don’t really know why my compression pieces have been breaking, I don’t know if I haven’t been putting enough glue on each joint or if the size of the cross pieces is the problem, but I’m gonna going up in size for the compression cross pieces first and seeing how that works.
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Re: Boomilever B/C

Post by Lorant »

scioly2345 wrote: Fri Oct 18, 2019 10:50 am Anyone have any suggestions when it comes to cross piece sizes?
Since the breaks of my recent boomis where just compression, I’m thinking of going from square 1/16 to possibly 1/8 by 1/16 or 3/16 by 1/16 cross pieces in the compression piece.
I don’t really know why my compression pieces have been breaking, I don’t know if I haven’t been putting enough glue on each joint or if the size of the cross pieces is the problem, but I’m gonna going up in size for the compression cross pieces first and seeing how that works.
In my experience, fairly dense, square 1/16 is the best for base cross pieces, no exceptions. If anything, you may want to look into the density and grain of your cross pieces, or their arrangement.
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Re: Boomilever B/C

Post by 123445 »

Any tips for the base. Since with 8cm width requirement the base that I used to use won't be viable anymore since I was using just a small piece of bass then laminating it. ( Used narrow booms last year )
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Re: Boomilever B/C

Post by MadCow2357 »

123445 wrote: Sat Oct 19, 2019 3:39 pm Any tips for the base. Since with 8cm width requirement the base that I used to use won't be viable anymore since I was using just a small piece of bass then laminating it. ( Used narrow booms last year )
Generally the base doesn't touch the wall so I don't think you'll have a problem? Maybe I'm reading the rules wrong but that's my interpretation anyway.
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Re: Boomilever B/C

Post by BigBootyBason »

MadCow2357 wrote: Sat Oct 19, 2019 6:43 pm
123445 wrote: Sat Oct 19, 2019 3:39 pm Any tips for the base. Since with 8cm width requirement the base that I used to use won't be viable anymore since I was using just a small piece of bass then laminating it. ( Used narrow booms last year )
Generally the base doesn't touch the wall so I don't think you'll have a problem? Maybe I'm reading the rules wrong but that's my interpretation anyway.
I think he's saying his boom last year were a lot narrower compared to this year. And since this year's booms are gonna be wider he isn't sure how to account that for the base bc his base was also narrow.
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Re: Boomilever B/C

Post by LoneMonkey »

sciolyperson1 wrote: Sun Oct 13, 2019 12:39 pm
LoneMonkey wrote: Sat Oct 12, 2019 8:48 am Since the compression beams will have to be "diagonal", how will the loading block fit on top of this? I'm new to Boomilever, but it seems that in the past, people made the outside edges of their compression pieces exactly 5cm and put their tension pieces around that.

Would making it in one diagonal and one straight part, then gluing them together work? (Similar to towers in '18). Or would that break too easily?
It wouldn't break to easily as long as the connection is built correctly, make sure to gusset the connection and add an extra horizontal bracing or two as well.
So then would this be the best option for boomis this year? Or is there a way to make the loading block fit on "diagonal" compression pieces?

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