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dragonfly
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Re: base

Post by dragonfly »

Thanks.
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Re: base

Post by Balsa Man »

Going back to SLM's diagram.....

If you extend the line of member #1 (the vertical upper leg) straight down, and,
call the angle between it and the sloped lower leg (#2) "b", and
call the vertically applied force (down through #1) F1, and the force on #2 F2
Let's say we're talking about a 3-legged tower, with a 15 kg load. Each leg is carrying 1/3 of the load, so F1=5kg

then, F2 = F1 x (1/cos b). You can get to this relationship either thru vector addition, or empirically playing around in the jhu app (mentioned/link to it provided previously)

so, if #2 were vertical, F2 would =1 x F1, or 5kg;

if #2 is at 8 degrees from vertical (b=8 degrees), F2 = F1 x (1/0.9902) = F1 x 1.0099, or 5.05 kg

or if #2 is at at 16 degrees from vertical (b = 16 degrees), F2 = F1 x (1/0.9611) = F1 x 1.0405, or 5.2 kg,

and, if #2 is at an angle of 28 degrees from vertical (b = 28 degrees), F2 = F1 x (1/0.8833) = F1 x 1.1322, or 5.66 kg.....
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Re: base

Post by Bubba1960 »

O_O
My mind cant comperhend stuff like that...
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Re: base

Post by SLM »

Bubba1960 wrote:O_O
My mind cant comperhend stuff like that...
You are underestimating your mind's ability to comprehend seeming difficult content. Spend more time thinking about it, ask questions, discuss it with your coach or teacher ...
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Re: base

Post by iYOA »

SLM wrote:
Bubba1960 wrote:O_O
My mind cant comperhend stuff like that...
You are underestimating your mind's ability to comprehend seeming difficult content. Spend more time thinking about it, ask questions, discuss it with your coach or teacher ...

also, because this forum is not LaTeX enabled, stuff like this looks a lot messier than it actually is.
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Re: base

Post by lllazar »

Bubba1960 wrote:O_O
My mind cant comperhend stuff like that...
Think about how the force on the member changes as the angle changes from vertical. Read it over a few times.
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Re: base

Post by robotman »

iYOA wrote:
SLM wrote:
Bubba1960 wrote:O_O
My mind cant comperhend stuff like that...
You are underestimating your mind's ability to comprehend seeming difficult content. Spend more time thinking about it, ask questions, discuss it with your coach or teacher ...

also, because this forum is not LaTeX enabled, stuff like this looks a lot messier than it actually is.
LaTex is you just need to use the

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Re: base

Post by lllazar »

So i finally got around to uploading pics of my base jig today, they should be in the gallery as soon as they get validated.
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Re: base

Post by iYOA »

i was looking at the pictures. Do you make an all 1/16in tower?
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Re: base

Post by lllazar »

No i use 1/8 why do you ask?

If your talking about the small size of the edge slots which hold the legs in place while assembling, the edges are two 3/32 squared pieces, i did this so that theres less of a chance of the leg sticking to the edge piece - if the edge was exactly 1/8, the 1/16 cross bracing would come RIGHT over the edge piece, so it'd be a tight situation the way i saw it.

This still works fine though, im open to any more questions.
2011 Season Events~

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Towers (Regionals ~1st) (State ~3rd)
Helicopter (Regionals -3rd gahhh) (State ~5th)
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