DIY: Build a Onager Catapult

It's really toy-sized, but it could be scaled up to fling, oh, say, a Volkswagen.
From Popular Mechanics http://www.popularmechanics.com/home/how-to-plans/woodworking/early-adopter-build-this-onager-catapult-11556480?click=pm_news
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wrote:

Ever since Northern Exposure, I've been a Trebouchet fan-- http://www.trebuchet.com /
Seems like the end of every season they'd fling a pumpkin-- or a VW-- or a piano.
Jim
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Ah, the Pumkin Chunkin Annual Contest for such devices is only two months away
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On Sun, 12 Aug 2012 20:18:34 -0500, HeyBub wrote:

adopter-build-this-onager-catapult-11556480?click=pm_news
My boy and I homebrewed one for a school science fair project of his a few years ago; it was only about 9" long but would happily throw things 20' or more.
As for trebuchets, there's a nice one at Warwick castle in the UK, complete with winding treadmills, for anyone who happens to ever be over that way. (
http://www.patooie.com/temp/warwick_trebuchet.jpg )
cheers
Jules
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So here is the results of this afternoon in the shop.
http://douglasjohnson.org/pictures/Onager.jpg
This is a great project with my grandsons, 6 and almost 4. It pops pecans about 20 feet.
I ripped a 2x down to 1x1s. The older one watched safely out of the way with safety glasses and ear muffs. Then he learned to read a tape measure as we marked and cut to length. We also had to make a Lowes run to pick up screws and the gate latch.
Then the three of us took turns spreading glue, drilling pilot holes, and driving screws. Grandma donated a wooden spoon to use as a throwing arm. That worked great.
As built, the pecan comes off the arm in very flat trajectory. You can double the range by tilting the front up so the pecan comes off at about 45 degrees. It wouldn't be hard to built a frame base to make that happen.
I know you often say "It's for the children" sarcastically. Not this time.
Thanks, Doug
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Neat little project, but I don't get the wheels. What? Gonna be drawn by a team of hamsters? Gonna enter it in a Pinewood Derby, driven by Baron Otto Matic? ;)
"You can do it, Tom boy" nb
--
Definition of objectivism:
"Eff you! I got mine."
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Two answers. I mean, how you besiege a sand castle without wheels? Tell me that.
More seriously, the plans showed wheels, the boys wanted wheels, so we got wheels. -- Doug
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They need a team of strong toy oxen to pull the catapult around.
Christopher A. Young Learn more about Jesus www.lds.org .
Two answers. I mean, how you besiege a sand castle without wheels? Tell me that.
More seriously, the plans showed wheels, the boys wanted wheels, so we got wheels. -- Doug
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That does look fun. I don't have a wood shop, and I don't have two grand sons. But, if I did, I'd sure build one of these. Looks like the kids are having fun. And, it doesn't have electronic screen, and runs on lots of batteries. Just good old imagination.
Christopher A. Young Learn more about Jesus www.lds.org .

http://www.popularmechanics.com/home/how-to-plans/woodworking/early-adopter-build-this-onager-catapult-11556480?click=pm_news
So here is the results of this afternoon in the shop.
http://douglasjohnson.org/pictures/Onager.jpg
This is a great project with my grandsons, 6 and almost 4. It pops pecans about 20 feet.
I ripped a 2x down to 1x1s. The older one watched safely out of the way with safety glasses and ear muffs. Then he learned to read a tape measure as we marked and cut to length. We also had to make a Lowes run to pick up screws and the gate latch.
Then the three of us took turns spreading glue, drilling pilot holes, and driving screws. Grandma donated a wooden spoon to use as a throwing arm. That worked great.
As built, the pecan comes off the arm in very flat trajectory. You can double the range by tilting the front up so the pecan comes off at about 45 degrees. It wouldn't be hard to built a frame base to make that happen.
I know you often say "It's for the children" sarcastically. Not this time.
Thanks, Doug
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On Wed, 22 Aug 2012 18:52:51 -0500, Douglas Johnson
Onager Catapult:

Good one. I like the use of the wood spoon.
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