Q&A for How to Build a Strong Catapult

Yes, as long as you use similar proportions. Keep in mind that a smaller catapult will not be very strong, nor will it be able to throw as far.

It is not recommended. The (slightly flexible) rope is good for strength and support. It gives the catapult momentum when it is tightly coiled.

Stronger stature and a stronger material to pull back the arm of the catapult.

Put them on the back and front of the base, use smaller wheels like from a go kart tire.

No, but you can release the catapult at different heights. This will allow the projectile to travel different distances

Yes, because it allows you to increase the tension which allows the lever/arm to rotate around the fulcrum.

You need to know the angle at which the projectile is released and the initial velocity of the projectile. Then you can use some of Newton's formulas like v^2 = u^2 + 2*a*d, and rearrange to find d.

The length doesn't matter as long as you tension it right, and as long as you make sure it won`t come loose.

You can just use a rope or just a strong string.

It depends on how bad the break is. If it is completely broken (a whole part snapped off), then no.

The base is around a 2x4, and all the other pieces are under 30", so a little bit smaller than the base of a chair.

They would have to be around three inches long to reach into the wood and provide sturdy support.

It is actually pretty small. You should be able to pull it off just right with a rope with ⅛" as the diameter.

If it is built correctly, it will mostly be accurate. However, it can still have some misses and minor splash hits.

I don't think it matters, as long as there is enough tension to push your arm and get the payload moving.

You should probably double the size.

No, you need a sturdy material for the main elements like the crossbar and the arm. Otherwise, it will collapse from its own weight.

It is based on how you've made your catapult or how much you've tightened the rope.

Make sure to have your arm at a 45-degree angle if you want it to launch farther. Keep in mind that a strong base makes a big difference. Finally, simply follow the instructions, and use the correct materials and dimensions.

When you face the crank handles from the side, you want to turn them the same direction as the catapult arm would move when launching the projectile. For this project, the left side would be turned clockwise and the right side would be turned counterclockwise. Make sure to turn both sides in equal increments (for example, 10 turns to the right and left sides).

This depends on the string you use and how far you pull it back. If you want to launch heavier items you should used stronger string and pull back the arm further.

Yes, water balloons make excellent ammunition for a catapult.

It can, depending on how sturdy it is and what type of string or rope you use. It also depends on the person operating it––if the person knows how to launch it, then it might launch 4 times the distance.

Yes, but it would a lot heavier than if it were made out of wood, plastic, etc.

It ranges from 10 - 30 inches. I would recommend making a 15-inch-long lever.

Just make the lever smaller, or raise the handle higher up.

It is a torsion catapult. This means it uses the twist of the rope to generate the force that swings the rope.