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Discussion Starter · #1 ·
I just can't figure this out.

Tre 1 (the smaller trebuchet was tossing water ballons to roughly 35 feet with deadly accuracy (could've put em in a 5gal bucket every time).

SO.......I added another stone (hastily....but miles of shrink wrap and duct tape are as good as steel and carbon fiber)......and didn't gain a foot of distance.

What gives?

It makes me call into question the awesomeness of The Beast (the large tre).
I doubled the size (frame and throwing arm dimensions), and at least quadrupled the counterweight (to like 350).........but now I'm worried it'll go 70 feet.
70 feet????....for all that. I planned on using it as a Pumpkin Skeet Thrower after the boy's BDay Party.

More weight should equal more force....yes?
 

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You are dealing with square roots. So doubling only yields a small increase.

 

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Discussion Starter · #5 ·
You are dealing with square roots. So doubling only yields a small increase.

I get the words.....the equation is.....beyond me.

Put it in layman's (6yr old) terms.

Longer arm.....longer runway/and string......higher pivot point?
 

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You should have to square the arms length and the weight to get double the distance.
 

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Discussion Starter · #9 ·
I have a translator working on the problem (head of the Math Dept. at VMI).

I sent him Robie's link and the pics........waiting for answer in "regular guy" speak.

Is Leo saying longer payload side of arm?
 

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Yes, and weight too. The secondary arm needs to maintain a 3.75:1 ratio.
 

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You need more speed. And you are limited in your speed by the size of your circle. Longer arm and same ratio of weight and speed will yield a similar rotation speed. But because the arm is longer you will gain speed because you are covering a much greater distance in the same period of time.
 

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Discussion Starter · #12 ·
I think the weight is sufficient.

Like 350 on the big one......

Gonna temp in a longer payload arm section tomorrow AM.....see how she reacts.

Does the pouch release string have to grow with it though?

My issue is size of circle....if that has to grow......it ain't happenin'.
 

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He wants more distance.
 

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Discussion Starter · #18 ·
Jaw dropping, and kid soaking, water balloon hurling. (Alex's 8th BDay......scavenger hunt to team color-dyed-water gun war in labyrinth cut into 5' tall pasture.....Dad manned siege weapons for
added drama of war)

I mean.....they are cool for kid chit...

but i just can't understand why I am getting almost zero increase in distance by doubling the weight on the small Tre.....

plus, I spent the morning building the big Tre and am now worried (haven't test shot it yet (concrete setting up).....need help, or pulley system to even load it)) about the WOW factor of it.
 

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Discussion Starter · #20 ·
Dude?????????

Amazing......:clap:

That thing says I get 397 feet out of The Beast (if my ballpark (short term memory) numbers are correct.

F that.....I'm grabbin a Fatmax 16 and going to measure.

THAT IS SICK!!!!!!!!

Where were you (and your fancy websites) yesterday.....?
 
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