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Why won't my trebuchet work? Answered

Over the weekend, I built a trebuchet. It is two feet tall from base to arm, and it uses a 2.5 pound weight as a counterweight. It will only launch a golfball around 8 feet! It has barely any arc at all. Can somebody help?

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BurfBest Answer (author)2009-11-30

Just from the looks of it, you may need to adjust the pivot point of the swing arm and/or the length of the sling. I would try moving the pivot closer to the counterweight.
Things to check:
Is the sling releasing cleanly?
Is the release point at or near 45 degrees?
Is the projectile hanging in the sling pouch?
Is the counterweight heavy enough?

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frollard (author)Burf2009-11-30

I would say add more weight and move where the fulcrum is to get more speed less torque - look at all the other trebuchet plans on ibles here...note how they have a 3 or 4 - to - 1 ratio of length.

More weight = more oompth.

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Lunar1210000 (author)frollard2010-03-31

you need to get a certaint amount, too much and it will still fly bad

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frollard (author)Lunar12100002010-04-10

Definitely - that comment was based on the particular design why 'this' one doesnt work well - all based on leverage, and ratio of weight to armature length(s).

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wck6 (author)2009-11-30

make a ledge about 6 inch up that the counterweight will land on, ajust the height of the ledge if needed

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Sandisk1duo (author)2009-11-30

the release point has to be at ~45 degrees

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