How to build a trebuchet ? ? ? ? ? ? ?

[J. Clarke]

example --hurls pumpkins over a quarter mile. Hurls Buicks lesser distances.

[Silvan]

Yup. The real ones can throw Volkswagens. :)

counterweight I've seen someone use on one of these things.

[U-CDK_CHARLES\Charles]

remembering that strenth varies as the square of linear dimension but weight by the cube.

[mac davis]

and note that the counterweight should be about 16 times as heavy as the projectile..

[jtpr]

"He was a quiet man..."

[Lazarus Long]

quiet at work. does his work, goes home. what more could the company want?

[Silvan]

I guess my arm is too thick, or too short, or something then. It runs on roller bearings, so friction has practically nothing to do with it. A baseball weighs, what, about 5 oz. I think. My counterweight is about 65 pounds. So I've got about 208 times the projectile for weight. It ought to throw the thing further than a piddly 100' it seems like.

Too much energy directed into up, and not enough forward maybe. Could be. I did have a little whoopsie. I guess the statute of limitiations is up. We were throwing rotten apples at the gigantic concrete wall near my house. Splat, splat, splat, whooooosh. Oops. Threw one right over that 20' wall and onto the highway on the other side. If anybody asks, kids, I was just over here yelling at you for throwing apples at the wall. I had nothing to do with this. :)

No glass, no horn, no crunch, no harm, no foul, but we put the treb away and that was the last time we played with it. There's no longer any place to shoot the stupid thing since all that stuff went up, and I sure don't want to get somebody killed.

[Old Nick]

On 14 Dec 2004 09:21:15 -0800, "jtpr" vaguely proposed a theory ......and in reply I say!:

remove ns from my header address to reply via email

Referring to what people who "knew" him say about some guy who suddenly blows away 20 people in some restaurant or whatever?

[mac davis]

more weight is usually better, but the distance will stop at a certain weight no matter how much you add..

arm size, length and balance are critical, as I recall, haven't built one in a few years and mine were LOW tech for sale purposes... no screws, glue, metal, etc... all wood except for the bit of string & cloth..*g* I seem recall that the best balance point is having the pivot "20% to

25%" behind the front of nose of the beam.. I think we used to figure that the distance from the pivot to the hook was 4 times the distance from pivot to nose, or something like that..

[Chip Olson]

Here's the one a friend of mine built out of his son's Tinkertoys:

I have weird friends.)

[foggytown]

Has everyone in here forgotten the satisfying effectiveness of a well-thrown Molotov cocktail? Keep it simple, folks. Keep it simple. FoggyTown "Cut to shape . . . pound to fit."

[Icepick]

with a bumper sticker that read " Driver only carries $20 worth of ammunition .... and an UZI "

[mac davis]

no, I'm not driving erratically, I'm reloading..