8 replies to this topic

[Dan Wask]

Well, Dave knows well that I got real freaking bored the last few nights. I had talked about building a catapult, and I did. And its freakin' awxsome.

Well, heres the general overview of the catapult. I used a triangular base design for stability, and strength.



Now this puppy is what drives it. Its around 45 assorted rubber bands wound together to form a ginormous band that has more resistance than a bungee cord.



This is the catch mech. Its basically just two posts that the pivot arm lowers down into and is held in place with a nail. As soon as you pull that pin, that arm goes flying up. I have a few bruises on my hand from this sob hitting me accidentally.

In the first picture, you can see the arms supporting the stop bar. I have several lengths of stop bar to allow easy ajustment of height and distance.

Edited by Dan Wask, 27 October 2004 - 07:33 PM.

[THIRST]

Beautiful, I quite honestly didnt think it would be done for awhile. Im glad you ended up not quitting. That thing is cuh-razy!

THIRST

[Dan Wask]

I guess I shoulda said that it fires bouncy balls, and, the bucket is made out of foam craft sheet.

<g>

[FIDO]

That thing looks dangerous. What are it's ranges?

[rosebud]

Ha looks good,

This past summer I made a trebuchet(sp?) about 5 feet tall, and that thing is crazy.
It gets about 100 ft launching baseballs.

Ill try to get some pictures of it later.

[Dan Wask]

Around 45-50 feet on the current angle that I have it on. With a different placement on the stop bar I could get farther probably.

[Jlego]

Yeah, we're making catapults/trebuchets in my school's physics engineering club. I can't wait to get started.
My favorite site is www.siege-engine.com
It's hot. After this I want to get the club to make torsion siege engines. As the end of year project we want to put the bio lab rooms under siege. That will be the peak of my high school career.
I'll post plans for mine as soon as I can, it's hard to draw something really complex that's 3D in 2D. I don’t know how to computer generate a 3D model either, so we'll see.
-Jlego

[Dan Wask]

Torsion ones are where you use roped spun together really tightly right ? Then theres a catch and when you remove the catch the torsion swings the arm forwards ? Thats orgoinally what I was going for, but for some reason the elasticity of the rubber bands wouldn't let it work well. So I modified the design a bit. Also, if any of you guys have pictures of your catapults postem up !

[AirApache]

My Latin class (yes, I'm taking Latin...I'm that much of a dumbass) has a convention in a few months, and a friend of mine and I have to build an onager. I'm asking ompa to help out a bit...perhaps when we finish we can post our own results. Most of you will be able to build it as our stuff can easily just be bought at a hardware store or someplace like Menards...

Onagers are sweet-a.

AA