Luke's Projects

Luke's Projects

Siege Equipment

Models

Games

Miscellaneous

Past, present and future creations. Mangonel Dalek Javscript-based Harmonograph

Front Page Trebuchet Maglev The Bonus Box Arcade machine

Links Roller Coaster Raft Race

Trebuchet

Video of the trebuchet firing (600kb)

My trebuchet

A trebuchet works with a hinged arm, one end has a heavy weight, and the other a sling. The full size siege weapons can hurl boulders kilometres, my trebuchet is 65cm tall in total, and 30cm to the top of the frame and can hurl marbles, conkers and bouncy balls over 7 metres.

counterweight My trebuchet uses dowel as a hinge, and the counterweight is made from two old pots filled with sand. The lids of the pots are screwed to a short length of wood with two eyelets at the end. At one end of the arm are two more eyelets and to hinge the arm and counterweight I line the eyelets up and put a small length of metal rod through them. A minor problem with my counterweight is that wood isn't long enough, so it doesn't always hang vertically. However this doesn't seem to impair it in any way.

My first trebuchet used a shorter frame and a fixed counterweight, a box filled with marbles. It worked, but never as efficiently as I'd liked, after doing some more research across the internet I decided that this was probably because of two things; the weight was too light and the hinge for the arm was too low. If I was the raise the arm then it would be able to get a larger swing, which a heavier weight would also help with.

the new frame I did this by gluing two lengths of wood to the side of the A frames. Unfortunately, I had to replace my plank of balsa wood with a bend piece of card because the new counterweight would hit the balsa on it's way around.

Luke's Projects	Siege Equipment	Models	Games	Miscellaneous
Past, present and future creations.	Mangonel	Dalek	Javscript-based	Harmonograph
Front Page	Trebuchet	Maglev	The Bonus Box	Arcade machine
Links		Roller Coaster		Raft Race

	My trebuchet uses dowel as a hinge, and the counterweight is made from two old pots filled with sand. The lids of the pots are screwed to a short length of wood with two eyelets at the end. At one end of the arm are two more eyelets and to hinge the arm and counterweight I line the eyelets up and put a small length of metal rod through them. A minor problem with my counterweight is that wood isn't long enough, so it doesn't always hang vertically. However this doesn't seem to impair it in any way.
My first trebuchet used a shorter frame and a fixed counterweight, a box filled with marbles. It worked, but never as efficiently as I'd liked, after doing some more research across the internet I decided that this was probably because of two things; the weight was too light and the hinge for the arm was too low. If I was the raise the arm then it would be able to get a larger swing, which a heavier weight would also help with.
	I did this by gluing two lengths of wood to the side of the A frames. Unfortunately, I had to replace my plank of balsa wood with a bend piece of card because the new counterweight would hit the balsa on it's way around.