Q&A for How to Build a Trebuchet

If built right, the superior siege weapon can fire a 90 kg projectile over 300 m.

Trebuchets are superior to catapults, balistias, and all other siege weapons invented in its era. They can use a counterweight to launch a 90 kg projectile over 300 meters.

There is a pin to hold it in place, and it's attached to a string you pull to launch the trebuchet.

The string has to open so that the tennis ball (or whatever projectile you're using) can get out of the pouch.

Yes, but it will be hard to make a big one. For a small trebuchet, Legos are a very good material.

Home Depot or Lowe's may be the best places to go. There is a list of required materials at the bottom of the page.

The approximate same length as the swing arm to the axle. For more information, watch the MythBusters build one.

It depends on how large the counterweight is. There is no "largest" counterweight, so this question cannot be answered to any more specificity.

The ratio for projectile to counterweight is 1:133. Mostly anything will work if it fits in this ratio. For example, for firing a golf ball, a good idea is a 14 lb bowling ball.

As big as you make it. It should have a 2 foot base or larger to be a viable outdoor trebuchet.

You can if you have the right pieces, but it would be better to use something like Lego bricks because of the strength that they have.

You can operate it from a short distance if you have a way to rotate the trebuchet's arm without touching it. Otherwise, you will have to touch the trebuchet.

Possible it would work, but it'd be a lot less effective due to the increased friction.

Yes, trebuchet is an Old French word that means "siege engine." It's derived from "trabucher," which means "to overturn or overthrow." Even when other countries such as England and Germany adopted the siege engine, they kept the original French name.

A traditional medieval trebuchet was used as a siege engine. They would launch large projectiles such as stones or bricks at the walls of enemy castles to break them apart. They would also launch projectiles over the walls to hit the enemy soldiers inside.

A good length ratio to use for a trebuchet is either 4:1 or 5:1. That means that the long part of the arm is either 4 or 5 times longer than the short arm with the counterweight. Keep in mind that the larger the ratio, the heaver the counterweight has to be in order to provide enough force to launch the projectile.

Only on very small ones. If you use hot glue one one more than half a foot tall, it will not work.

Use a cloth to make a sling like on a slingshot and then tie two pieces of rope to the cloth. Make a loop on one of the pieces of rope and screw the other one into the side of the top of the arm. The loop goes on a nail without a head sticking out of the very top so when you shoot one end of the rope is detached and the projectile will be released from the sling.

No. If you do this, it will just stay in the pouch because of centripetal force. As the pouch swings around, the projectile will be stuck in there.

The sling on the end of the trebuchet releases upon an angle α, at which point the counterweight does no more work on the projectile. One can change this release angle by adjusting the angle of the holding pin at the end of the lever arm.