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Old 04-12-2010, 09:37 PM
64coupe 64coupe is offline
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Default Catapult Contest

My company is holding a catapult / trebuchet contest for employees only. Basic rules - must fit in a 3'x3'x3' box, mechanical system. Current rules have us chunking a full 20 Coke bottle.

Starting research tonight. What type would you guys go with?
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Old 04-12-2010, 10:12 PM
Don_S Don_S is offline
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How about a mortar?

Don
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Old 04-12-2010, 10:20 PM
redfarm
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built a trebuchet for stepdaughters class last yr. I will try for pics tomorrow night. I found out later that having a pivoting counterweight is key.
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Old 04-13-2010, 07:09 AM
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http://www.tbullock.com/trebuchet.html
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Old 04-13-2010, 08:02 AM
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If it has to fit in a box and an arm cannot be extended, then some sort of torsion device may be more powerful. (mangonel or onager)

http://www.stormthecastle.com/catapu...n-catapult.htm

http://www.medieval-castle-siege-wea...catapults.html
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Old 04-13-2010, 08:10 AM
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use a screw to load power into a truck spring.
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Old 04-13-2010, 08:49 AM
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trebuchet.com enough said... reccomend the floating arm style. you will need to scale it i'm sure.
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Old 04-13-2010, 12:25 PM
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Does it have to be a catapult/trebuchet, or does it just have to throw a bottle and fit in the box? What exactly do you mean by "mechanical system"
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Old 04-13-2010, 01:51 PM
kbs2244 kbs2244 is offline
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If there is no requirement for traditional materials,

I see a garage door torsion spring wound real tight,
with launch lever on one end.
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Old 04-13-2010, 02:14 PM
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The all-knowing young one mentioned a torsion bar type ballista using flat truck springs.
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