I designed this simple trebuchet as a more stable, robust small trebuchet. The two opposite side frames are braced against each other so it doesn't need guy lines, which is the main problem with the older trebuchet design on Ropes and Poles. The Troop Scouters of the recent Gauteng Scout Wood Badge course at Arrowe Park tested it out and verified that it works (two of the patrols promptly ganged up on the third to send a shower of over-ripe tomatoes across to them). The theme of the Wood Badge weekend was 'the Knights of Gauteng' so this is the Knight's Trebuchet.
1. Build one 'A frame'- make sure there is enough space at the top for the throwing arm to rest.
2. Tie the base lashings of the second (yellow) 'A frame'/triangle and attach it to the first A frame
3. Lash the top of the yellow A-frame, making sure the crossing lines up with the green A-frame
4. Lash the two base poles on to the two frames.
5. Attach the throwing arm, which is lashed onto it's axle. Rest the axle in the forks on the top of the a frames, and 'mouse' the top of the fork to prevent the arm jumping out.
This trebuchet was tested with and without a sling.
The SketchUp model is available for download HERE.
2 comments:
Thank you for this design. We tried it out today - worked very well.
The order of the construction is important.
It was stable, relatively simple, and effective. We did it without a sling.
We sued a rope launcher (not elastic) - Elastic fails at the point where maximum impact is needed when the arm if 45 deg to vertical. Apoint to note is that the arm should be lashed to its axle with 1/5 on one side (the pulling part) and 4/5s of its length on the throwing side.
My sons, one of their friends, and I built and used this today. It worked great! Thanks for the design!
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