mini catapults can be used to do many things in contrast to normal catapults.here is an awesome list of catapults for you to build.



Build the Table-Top Troll Catapult. This is a great little siege engine that really hurls projectiles! You just need some wood, a few screws, a rubber band and a couple of hours. This little catapult really hurls projectiles. And you can really tweak it to be quite a powerful little troll.
table top troll catapult logo
table top troll catapult logo

This is a tiny replica of the massive siege engines that were used to tear down castle walls in the Middle Ages.
This tutorial on how to build a catapult takes you through all the steps in showing you how to do it. Want to see it in action? Here is a quicktime video of this catapult in action - Table Top Troll Catapult video.
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What do you need to build this catapult?
Parts list for the catapult
Parts list for the catapult
Parts List: You don't need a whole lot of parts or tools to make this catapult and this is just a suggested list and these are the parts I use to make the catapult in this tutorial. You can fudge and replace lots of the parts. If you are creative there is a whole host of parts and things you could use instead of these parts. As you can see though it is pretty basic and you don't need a lot to build a basic catapult.

parts in the picture:
  • 3 pieces of wood 12 inches long
  • 8 pieces of wood 6 inches long ( two of these pieces have the ends cut at 45 degree angles - I will explain more about these.
  • An assortment of small screws and/or nails
  • 1 large rubber band or several smaller ones
  • 2 eye hooks (to the right of the rubber band
  • Some glue (optional but a good idea)
  • 1 four inch square piece of cardboard or poster board (This is the basket that your projectile sits in
  • 1 metal bar at least 6 inches long, I am using the axle from an old toy car (thats the wheels)
the catapult pivot
the catapult pivot
About the metal bar from the axle: This is what I am using but you can use almost anything similar. This is going to be the pivot point for the catapult arm so you need something thin and strong. Here are some suggested things you could use: very firm coathanger wire - the cut off blade of a screwdriver, the metal bar handle from a bucket. Take a look at the close up of the catapult arm pivot on the left. See how it is going to be installed. So think of this and find some kind of metal bar for this. If all else fails you could even use a pencil or a pen. You would just have to drill a hole large enough for it to pass through. I used the axle from a toy car which works perfectly. So you may want to scrounge through your toy box to find one.
That's pretty much everything unless you want to paint and decorate your catapult. So lets start on the tutorial and make one ourselves!
Let's begin the assembly of our catapult
First gather all your materials and then cut the wood into the required pieces. You can use almost any size wood and I used some scraps of wood that are 1 inch by 1 half inch wide. Cut it into several pieces like this:
  • Cut 3 pieces twelve inches long
  • Cut 8 pieces six inches long
cut two pieces like this
cut two pieces like this

Now of the eight pieces you cut that are all six inches long cut two of them like the two in this picture. They are still six inches long but the ends are cut off at 45 degree angles. Make sure you cut the angles as shown.





assemble the first side of catapult
assemble the first side of catapult

Assemble the first side of the catapult just like this picture shows. I used glue and screws which is the best but you can improvise any way you want, nails and glue would be fine too. This is the support system for the swinging catapult arm so you want it to be sturdy enough to take a bit of a slapping of the arm against it. The line at "A" shows where the screw is. The line "B" shows the angle wood and the horizontal wood are about lined up on their ends.
both sides of the catapult
both sides of the catapult

Now build the other side but make it a mirror image of the first one. The two of them will look like this picture on the left. See how they mirror each other?






assemble catapult base
assemble catapult base

Now connect the two sides of the catapult together using the remaining four 6 inch pieces. The photo at left shows these four pieces. I used screws and glue to make it very strong.
Note: The upright wood pieces (the two vertical ones) are on the insde of the catapult base. Don't build it with these on the outside. It is stronger this way and you can use a shorter piece of iron bar.

Okay, we are doing great and it is starting to look like a catapult:
Let's work on the catapult arm
drill a hole in the catapult arm
drill a hole in the catapult arm

Drill a hole in the catapult arm abou 1/2 inch from one end. . This hole should just be a little bit bigger than the metal bar you are using.
axle
axle
Remember that I am using an axle from a toy car for my metal bar. I removed the bar from the wheels and the diameter of the hole I am drilling is just a little bit bigger than this axle. If you don't have a drill you could use a nail to punch a hole and gentle wiggle it until the hole is a good size. Drill your hole for whatever size bar you are using.
hook in catapult arm
hook in catapult arm

Now put a hook about three inches from the other end of the arm.

catapult cup
catapult cup

Now make the catapult cup by cutting and folding your 4 inch piece of posterboard or cardboard. then glue it to the end of the catapult arm. put it right up against the hook. This will close off the hook so you can squeeze the rubber band onto the hook and the cup keeps the hook closed and the band can't escape. there will be about an inch of wood sticking out past the end of the cup. This is perfect, it gives you something to press down on when firing the catapult. I used glue and a couple of thumbtacks to secure the cup to the arm.
assemble the catapult arm to the base
assemble the catapult arm to the base

Now it is a real snap to assemble your catapult arm to the base. Simply push the metal bar through one upright, feed it through the catapult arm then push the bar right into the other catapult upright. This picture shows it complete. Put a dab of glue on the bar at each upright so it will hold tightly and if your catapult arm is a bit loose you may want to put a few wraps of tape on each side of the bar near the arm so it is held in the center of the bar.

We are almost done building the catapult
catapult assembly
catapult assembly
Here is where we are at right now. We are almost done. We just have to add another hook, put on the rubber band and then decorate it!




finishing up the catapult
finishing up the catapult

Put the other hook on the front of the catapult. The arrow shows where to put it. Then run a rubber band from that hook to the hook on the catapult arm. If you don't have a rubber band that is long enough you can tie multiple rubber bands together . Experiment with the length so you get some good spring action.
Now don't forget to decorate your catapult. I painted most of it an old fashioned brown color and I painted the pivoting arm a light cream color. Of course I added the picture of the troll just for fun. And that makes it officially the "Table Top Troll Catapult!"

The catapult in the ready to fire position
The catapult in the ready to fire position

Here is the catapult in the ready to fire position. Notice the good tension on the rubber band. And notice how there is a little space to the left of the cup so you can put your finger and press down.
If you didnt watch the video of this catapult in action here it is: The Movie of the table top Troll catapult in action firing a ball of paper.
Note: You can adjust the angle of the catapult firing by moving the horizontal stop bar either up or down. Just remove the screws and glue then move it down and the catapult will fire the projectile on a higher arc



The Backyard Ogre
The Backyard Ogre

This is the Backyard Ogre Catapult
The base of this catapult is two feet long and the throw arm is about three feet long. It is made from 2x3's but you can make it from 2x4's also. It took me about two hours to make it.
This page is all about this catapult and how you can make one yourself.
Safety Note: This is a powerful catapult that uses a bungee cord as its power source. You must use safety precautions when building and using it! And you must absolutely wear safety glasses when firing it off. This is in case the bungee cord breaks. And never fire any type of solid object with it. I use balls of aluminum foil and it works just as well with a tennis ball.
Tutorial and pictures on how to make this catapult coming soon. Bookmark and check back.

See this catapult in action and learn more about it

How to Build the OGRE Catapult

Safety Glasses
Safety Glasses

A Note about Safety Before Starting! Please use all safety equipment when building and using this catapult! It is very powerful. Wear Safety Glasses and follow all safety rules if you are using tools and power tools. This project should not be done by minors without the supervision of an adult. Please be safe and never fire the catapult at a person or at someones personal property. Never fire any hard projectiles from the catapult.
The Parts Needed
The Parts Needed

Above is a picture showing all the parts needed to build the OGRE Catapult. I will describe them and tell you a little bit about them. Lets start at the left. You can see that there are some cut notches and some holes drilled in the wood. I will explain what these are and how to do them.
From Left to Right the wood: (All wood is 2x3) The longest one is not quite 2x3 because I used a scrap of wood that I had but you can use a 2x3.
  • 2 pieces each 7 1/2 inches long
  • 3 pieces 14 inches long
  • 2 pieces 24 inches long
  • 1 piece 28 inches long
  • 1 piece 10 1/2 inches long
The extra stuff along the bottom:
  • a cardboard cup (this holds your projectile)
  • 2 large and strong eye hooks
  • a bunch of long screws (you can use nails but screws are better)
  • a bungee cord that is 24 inches long
  • a broom handle, dowel or pipe that is about one inch thick and 12 inches long

Okay, once you have these pieces of wood cut to length lets modify a few of them. This is the hardest part and once you have this done the rest of the catapult goes together very quickly and easily. We are going to cut two of the pieces of wood so we can form them into a joint like that shown below. It's not that hard. All you need is a handsaw, a chisel and some safety glasses and gloves. Making this joint is important because it will make your catapult much stronger.
external image cut-the-wood-joint.jpg
Part 2: Let's Cut the wood to form our strong joint.
Take one of your 24 inch long pieces and put a mark 3 1/2 inches from the end. This is your pivot hole. Drill a hole here that your broomstick or pipe will slide through. (Do this same process on both of your 24 inch pieces.)
Then make a marks at 5/1/2 inches and 8 inches. Draw the lines for this as shown in the picture.
Mark  the wood
Mark the wood

Now lay your saw flat on the wood and cut down at both the lines so the cuts go halfway through the 2 x3.
Cut only halfway down
Cut only halfway down

Now use a chisel and hammer to chisel out the excess wood.
Chisel out the notch
Chisel out the notch

Repeat this process on your other 24 inch piece of wood.
Now lets do the two upright pieces. Do this process to two of the fourteen inch pieces. Only do one end of each piece! Mark a line 2 and 1/2 inches from the end and then cut down with the saw half way through the wood. Then chisel away the excess. Now this piece will fit nicely into the piece you made above.
Cut as shown
Cut as shown

Now that you have cut the notch into the 24 inch piece and cut the notch into the 14 inch piece they should fit together nicely like this:
Looks like this when assembled
Looks like this when assembled

You still have one remaining 14 inch piece and that is ok. Do not cut a notch in that third one. We will custom cut that one later.
Take your two 24 inch pieces and your two 7 1/2 inch pieces and screw them together as shown in this picture. Make sure that the notches you cut in the wood are on the outside of the assembly, not on the inside. Screw one of your big eye hooks into the end as shown. Make sure it is on the end nearest the slots and hole you cut in the long pieces. You can nail these pieces together but Screws are much better. Drill a pilot hole if you have difficulty getting the screws in. A pilot hole is a very thin hole drilled as a starter. It makes it easier for the screws to go in.
Build the base of the catapult
Build the base of the catapult

Now screw the two upright pieces into place.
Install the uprights
Install the uprights

Now screw your 10 1/2 inch piece across the top of the two uprights. Make sure it is on the side shown. It should not be on the side nearest the metal hook.
Install the Crossbeam
Install the Crossbeam

Now take the final 14 inch piece of wood and custom cut the ends so they are at an angle then screw it directly in place like shown.
measure and cut for strength
measure and cut for strength

This cut can be a little tricky but just carefully measure it by holding it up against the catapult and drawing lines on it. The piece shown here has already been cut at both ends with the right angle and just needs to be screwed in place. This piece is rathe important because it adds a lot of strength to the catapult.
Now let's assemble the swing arm of this catapult and install it. We are almost done here.
The Swing arm
The Swing arm

Take your 28 inch long piece and drill a hole in one end so your broomstick or pipe slides easily through it. It should be a loose fit so the swing arm will pivot freely.
Make a small cardboard cup and staple it down to the other end. This the the cup that holds the projectile. You don't have to make a cup you could cut down a plastic cup so it is about 2 inches deep and staple that down.
Now put your other eye hook onto the swing arm. Make sure it is nice and tight.
Lets finish this up! Slide the broomstick through one end of the catapult, through the swing arm then through the other end of the catapult. Put a couple of screws in it to hold it firmly in place. Then attach the bungee cord and you are ready to go!
The Completed Catapult
The Completed Catapult

I hope you had fun making this catapult and please be safe! USe safety goggles and never aim it anyone or anything. Remember to be conscious of the bungee cord and hooks. excessive pressure could cause them to snap. So be careful.

Tips on making your Catapult more powerful.

The Bungee Cord is the most important thing so using different cords will change the strenghth or adding a second cord.
The crossbar is very important in that it sets the angle that your catapult fires off. You can adjust the angle of fire by lowering or raising the crossbar on the uprights. Or you can use thinner or thicker wood for the crossbar.
The length of the swing arm also has an effect on how powerful the catapult is. Generally the longer the swing arm the more power you will get so try using a piece of wood that is longer than 28 inches.
external image axle.jpgThe pivot point (The hole in the swing arm that the broomstick goes through) is an important energy point. If it is too tight, or too loose it will absorb energy and decrease the efficiency of your catapult. Make sure it swings smoothly. And if you wanted to get real fancy you could use some kind of a bearing. I have made catapults using the axle of a bicycle for this pivot point. It really works well.



Make The Teeny-Tiny Catapult


The Teeny Tiny Catapult
The Teeny Tiny Catapult
This is a complete tutorial that will show you how to make the teeny tiny catapult. It's a really fun project that you can use in a lot of different ways. It lends itself to creating games of your own and one of the games I made with this catapult is the storm the castle game where I made a paper castle with window and door holes that you can shoot through for points. You can set up cups at varying distances and get points by shooting into them.


Popsicle Sticks
Popsicle Sticks

Need Popsicle Sticks? They are cheap and you can get them real fast from Amazon.com. This box should keep your craft making going for a while and will save you from having to eat all those popsicles.
external image ir?t=stormthecastl-20&l=as2&o=1&a=B000CCYOLWCraft Sticks - 1000 Boxed in Bright Hues by Chenille Kraftexternal image ir?t=stormthecastl-20&l=as2&o=1&a=B000CCYOLW


Let's Make This Catapult

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Here are the materials you need to make this catapult. Ten popsicle sticks, a ruler, a pencil, scissors, a rubber band, and a roll of masking tape. The rubber band, when cut, should be at least 5 inches in length. Before you start making the catapult take a look at the popsicle sticks and make sure they aren't cracked or weak.





Some Masking tape Tips before you begin

There are some neat tricks that I use when applying masking tape and you should use these techniques.
Tape Pieces
Tape Pieces
First off, cut yourself ten pieces of masking tape and stick them lightly to the table or the wall. This will make it easy to grab and use them.


Tape technique
Tape technique

Another great technique for using masking tape is to lay it on a table with the sticky side up. Then you can apply the craft sticks to it easily. And it makes taping two sticks together very easy.




The craft sticks cut into pieces
The craft sticks cut into pieces

Now cut the popsicle sticks so you end up with what you see in the picture above:
  • 3 pieces that are two inches long
  • 6 pieces that are four inches long
  • 1 piece that is three inches long (leave one rounded end on it)
  • 1 piece that is four inches long (leave one rounded end on it)
Now take two of the four inch pieces and two of the two inch pieces and tape them end to end so it looks like one big long stick. The sequence should be short stick, long stick, short stick, long stick. (like this picture):
external image four-craft-sticks-taped-together.jpg
external image tape-technique.jpgI tape them using the technique I described in the taping technique above. I lay a piece of tape on the table with the sticky side up then press the two ends of the sticks onto it. Wrap the tape around them with three solid and tight wraps.
external image wrapped-tight.jpg
Fold into a square
Fold into a square

Now fold the assembly into a square and tape the final joint together. It should look like the picture here on the left. Use plenty of tape.


Make The Teeny-Tiny Catapult 2

Place a piece on the inside like this
Place a piece on the inside like this

Now place a two inch piece on the inside of the structure like this.




Tape it tightly into place
Tape it tightly into place

And tape it firmly into place. Use at least three wraps of tape and do not put any tape in the center area of the sticks. I will show you why in the next picture.




external image keep-a-space.jpg
You will be inserting a stick into that space in the middle so that's why you should leave the middle untaped. But don't insert it now. We will do that later.




side by side
side by side

Now tape two of the four inch stick together side by side like this. You are going to do this twice. Make sure to use plenty of tape and do at least three wraps around.




Two sticks side by side
Two sticks side by side

Make two of these and this is what you end up with. Two assemblies each with two four inch sticks.





Tape it down to the rectangular base
Tape it down to the rectangular base

Now tape these assemblies to your rectangular base. First you put tape on the long end like this picture shows.





Tape it the other way too
Tape it the other way too

Then tape it the other way like this.






The Base is completed
The Base is completed

This is what you end up with. The base is completed and you are almost done. Just a few more things and one thing I want to point out about your taping so let's flip this base over and take a look underneath.





Triangles of tape
Triangles of tape

See how, underneath, the tape forms nice tight triangles? This will lend a lot of strength to the catapult base. So do at least three wraps and make it nice and tight.



Make The Teeny-Tiny Catapult 3

Tape band to stick as shown
Tape band to stick as shown

Now tape the rubber band to the three inch popsicle stick as shown by laying it on the stick at the rounded end then wrapping it with tape. Do at least four wraps and make it nice and tight.





Insert it into the base
Insert it into the base

Now insert that assembly right into the base of the catapult as shown. It slides tightly between the two pieces that are taped together. You will need to use a little tool to opend up a gap. Use a small screwdriver or the tine of a fork to get the gap to open up just a little then force the stick in there. It should be a nice tight fit and should stand upright nicely.




iinserted and looks like this
iinserted and looks like this

This is what it should look like.






four layers of tape
four layers of tape

Now we are going to make the hinge for the catapult. Stick a layer of tape right down on your table (sticky side down). Yup, stick it right to the table like shown at left. Then stick three more layers of tape right on top of it. You end up with a piece of tape that is four layers thick. Now peel this tape up off the table and ...


external image two-inches.jpg
and trim it to two inches in length.





external image trim-lengthwise.jpg
Now cut it lengthwise so you end up with two pieces that are two inches long.





external image markthem.jpg
Now, using two popsicle sticks as a guide, mark little lines about in the center of the tape pieces. This little area between the two lines is the actual hinge part.





external image tape-to-arm1.jpg
Now tape one of these hinge pieces to your remaining four inch popsicle stick. This is the flat end. The other end of the stick that you can't see in the picture is the rounded end. This is the arm of the catapult.




tape the other end too
tape the other end too

Put the other piece of tape on the other side of the popsicle stick so it looks likel this.






Tape it together
Tape it together

Now pinch the free ends of the tape together so they stick to each other. And wrap at least three wraps around the stick so it all holds together nice and tight.




Final look at the hinge
Final look at the hinge

You will end up with it looking like this. Make sure the tape is wrapped nice and tight. This is the hinge of your catapult and we will attach it to the base in the next step. Just remember that your little black lines on the tape are a guide to show you where no tape goes. That little free area is needed so the catapult hinges freely.



Make The Teeny-Tiny Catapult 4

Tape the arm into place
Tape the arm into place

Now place the catapult arm into the base as shown with the tab of tape pointing up and wrap at least five wraps of tape around it so it is firmlly taped to the upright piece.





tape the arm into place
tape the arm into place

This picture shows me taping the catapult arm into place. Do at least 5 wraps and make it nice and tight.






Test the catapult arm
Test the catapult arm

Test the movement of the catapult arm by moving it up and down. It should move freely. This is why we leave the little space between the black lines. It acts as a hinge.





Tape the rubber band to the catapult arm
Tape the rubber band to the catapult arm

Now tape the rubber band to the catapult arm. Tape it so in the relaxed state it is at about a 45 degree angle. This will give it some spring. Leave it long so you can adjust it if you need to.





mark the paper like this
mark the paper like this

Mark up your two inch square of paper like this. The lines are about a half inch from the edges. Where you see the green lines in my picture cut with a pair of scissors.





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Fold the paper into a square cup shape and tape it all together. Use plenty of tape.






Catapult is complete
Catapult is complete

Now tape the cup to the catapult arm and you are done!







Leave room for your finger
Leave room for your finger

Just make sure you leave enough on the end for you to press it down with your finger. Have fun with your new teeny tiny catapult and create some games with it.




How To Build A Trebuchet

The Little Dragon Trebuchet
The Little Dragon Trebuchet

Here are plans and pictures on how to build this medieval trebuchet. It is a siege engine that wreaked havoc in the middle ages and you can make this small 12 inch table top version with materials from around the house. Building this catapult-like weapon is easy and you can do it in a couple of hours. Without any tweaking or modifications this trebuchet launches a clay ball thirty feet. It is adjustable in several ways and you can build it to launch projectiles even further.
Here is a quicktime movie of this Trebuchet firing off
Trebuchet Movie
Medieval shield on trebuchet
Medieval shield on trebuchet

The Little Dragon Trebuchet - This Trebuchet Build Plan will take you about two hours to complete. Here is a parts list for easy printing

Trebuchets Built By Web Visitors

Photobucket
Photobucket
Is it possible to build this trebuchet successfully? It sure is! A web visitor has built one, and taken pictures. He has also made a nice little design improvement to it. His treb has a neat little locking bar so you can lock it in the ready position then pull the pin to fire it off. You can see pictures of his Trebuchet and his design improvement here.
John H. Trebuchet
John H. Trebuchet

Another great trebuchet project submitted by a web visitor. This treb is a big success and the builder has done some great research that will help you build an even better trebuchet! He also carefully explains the optimal weight ratio between the counterweight and the projectile Check it out here for some great tips and information
Adil's Trebuchet
Adil's Trebuchet
Here is a neat little project that somebody made (Adil). He made his trebuchet at half the size of the project here. And he did a little modification. Instead of using the long string and pouch he used a spoon to hold the projectile -- this is similar to how an Onager works. Nice work on this little trebuchet project -- it shows some good improvisation. He also made a little castle to assault with his siege engine and he created two videos that you can watch here Mini Trebuchet Project If you are having trouble with your trebuchet string and pouch these videos show a nice alternative. If you want to make a smaller one you should check this one out.
Gregg C Trebuchet
Gregg C Trebuchet
Here is another trebuchet that a web visitor built. It is by Gabe C. I call this one the Ferrari of Trebuchets because of the excellent custom paint job including flames! Gabe also made a couple of very nice improvements on my design that you might want to check out. Gabe C's Trebuchet
What You Need
The Recommended Tools for this project
Trebuchet building tools
Trebuchet building tools

  • Hammer
  • Saw
  • Screwdriver
  • Pliers (needlenose)
  • Wood Glue
  • File
  • Scissors
  • Drill and Bits
  • Sandpaper
  • Cutters for metal
Most of these tools are just recommended and you can vary the tools depending on what types of materials you use for this project. Here are some tips: Needle nose pliers are best for manipulating small parts but if you don't have any then any other type of pliers will be fine. The metal file shown in the center of the picture is recommended any time you work with metal - you should always file down cut metal so there are no sharp edges. The sandpaper shown is attached to a block; this makes sanding small parts easy and you should always sand every piece of wood you cut so there are no splinters.
Miscellaneous items needed to Make the Trebuchet
Trebuchet materials
Trebuchet materials

  • Heavy object (three different ones are shown on the far left) only 1 needed
  • Small screws
  • Small Nails
  • 2 eyehooks
  • wire or bread ties
  • Electrical tape (or masking)
  • 3 feet of string
  • piece of cloth - 6 inches.
  • Paints (optional)
  • 1 sheet of cardpaper -similar to cereal box (shown under the paints)
About the miscellaneous materials: The counterweight is very important and you should find something as heavy as possible. I used a chinese healing ball for my trebuchet but you can use items found around the house like batteries taped together, penny rolls taped together, a lump of heavy clay or even a rock. Special Note: You will also need a metal bar for the cross piece. I will talk more about this a bit later.
Wood Needed for the Project
Trebuchet wood required
Trebuchet wood required

  • 1 16 inch piece
  • 2 12 inch pieces
  • 2 10 inch pieces
  • 3 5 inch pieces
  • 1 square piece of flat wood about 5-6 inches
About the wood: The wood I used is about one inch by one half inch thick. You can be very flexible with this and use almost anything similar. You can cut strips of wood if you need to. The sheet of wood shown is important for strength and it is about one quarter inch thick but thinner would be ok.
Okay! This is everything you need to make this table top Medieval Siege Weapon. Let's start with the building instructions.
I lot of people are building this Trebuchet and I get a lot of email about it. One of the common questions is about my counterweight. Seeing as I use a solid metal Chinese Healing Ball it makes quite a difference and not everybody has these. So to get an idea of how much one of these balls weighs I made up a little scale and weighed the ball with pennies. It comes out to 147 pennies. This gives you a good idea of what to shoot for with your counter weight. If you use three rolls of pennies your weight is about the same as mine.
It was a kooky contraption I built but a nice little project: see the scale I made to weigh my counterweight
How To Build A Trebuchet
Let's cut all the wood for our Trebuchet first.
Using your long pieces of wood cut these lengths:
  • 1 - 16 inch piece; This is the swing arm
  • 2 12 inch pieces; These are the long base pieces
  • 2 10 inch pieces; These are the uprights
  • 3 5 inch pieces these are the cross pieces that complete the base



Now cut the triangle support pieces. This is easily done by cutting a piece of wood to a square about 5-6 inches on each side. Then draw a line from one corner to the other and cut across this line. It gives you two identical triangles. Shown in the picture at right is the square with the line drawn on it before cutting.
wood for the trebuchet base support
wood for the trebuchet base support



Build these two parts of the frame first. You should make these parts first because it will be much easier to assemble later on. Lay out one 12 inch piece of wood horizontally. Mark a line on it 3 inches from the left end. Place the ten inch piece of wood vertically at this mark.
external image base1.jpg


Now carefully place the triangular piece on this structure and glue it in place. Put nails or screws in it to make it stronger.
external image baseleft2.jpg


Do this again for the other side of the trebuchet but.... You have to do the other side of the Trebuchet but it is a mirror image. Mark off 3 inches from the other side (the right end) of the 12 inch wood and this is where you put the upright ten inch piece and the triangle wood.
external image mirroredbase.jpg


How To Build A Trebuchet
Assemble the Base and main frame of the Trebuchet Assemble the Base and the main frame of the Trebuchet.
Here you add some crosspieces to the sides you already built. This easily transforms your pieces into something that actually looks like a trebuchet. If you use glue in this portion you can set it aside to dry while you are working on the swing arm.



Take the two side pieces you just made and stand them up with the triangle pieces on the outside. Then glue and nail or screw the five inch cross pieces onto them (all three of them). It will look like the picture at the right.
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Look at your new structure. You can see at the very top of the uprights, in this picture there are black dots. Each upright will need a hole drilled in it at this dot. They are one inch from the top. You don't know yet what size hole to drill.. You will be inserting a metal piece across here and through these holes. When you find the metal piece you want then you drill the holes about the same size.
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Find a piece of metal bar that is at least five inches long. It has to be fairly strong to support the counterweight and the swinging action. Suggestions: A coat hanger might be ok, but some coathangers are too weak, make sure you have a very sturdy one. Or use the metal handle from a pail. You can even cut the blade off a long screwdriver and use that. Look around for something.
Do not insert the metal bar yet. You still have to make the swinging arm of the trebuchet.
Need a metal bar for your trebuchet? The axle from a toy car is perfect for this. Dig through the toybox and see if you can find something like this.
external image axle.jpg
How To Build A Trebuchet
Assemble the swinging arm



Take your sixteen inch piece of wood and insert a hoop hook in one end then make three marks. One three inches from the end, one four inches, and one five inches. Drill these as holes. Drill these holes just a little bit bigger than the metal bar you are using. You should be able to easily insert the metal bar and swing the wood around it smoothly.
external image drillthreeholes.jpg


In the other end of the sixteen inch piece insert another hook loop as shown and also insert a nail into the end of the piece. It should be at a slight angle. After inserting the nail cut the head off or file it down. You will make a loop that has to slide easily off this so if it ihas a head it might get stuck.
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Run your metal bar through one upright of the trebuchet then run it through your swing arm and finally run it right into the other side of the trebuchet. Important: The hookloop at the far end of the arm (yu cant see it here) should be on the bottom of the arm. Insure the trebuchet arm swings easily with no wobble and very little friction. It should swing nice and free.
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Make your counterweight
Tape up your counterweight. You can use almost anything heavy but not too big, AA batteries, a stone or some other item.like rolls of pennies. If you are having trouble with this you can always just wrap a bunch of metal objects or coins in a plastic bag- it will work just fine. Keep the overall size of the counterweight to about the size of a tennis ball or smaller. Now just tape your twist ties or wire to your counterweight and then loop it through the loop in the swing arm and the counterweight is ready. I made a twist tie loop and attached it to the ball. Then using a second twist tie I ran it though that and then though the loop on the swing arm then twisted it firmly,
How To Build A Trebuchet
Assemble the string and pouch

Cut two pieces of string at least 18 inches. You will trim this down later. Fold your cloth in half then tie each end with a string so it forms a nice little pouch. Take your time with this. It will come out fine.At the end of one of the strings attach a loop. More on this in next step. Shown here is a soft little clay ball for the projectile. Grapes work great and are safer.
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I made my loop out of the metal from a spiral bound notebook, its simply one revolution, You can use wire or anything else that is thin yet strong.
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Now attach your pouch to the arm of the trebuchet. It should be about 12 inches from the hoop shown here. The top loop will slide right off as the arm goes forward. This will allow the pouch to open and release the projectile.
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This string and pouch will rest right under the trebuchet so you need a little runway for it to ride on. I made a runway out of posterboard. Just fold up each side about one inch and then glue the runway right into the trebuchet.
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How To Build A Trebuchet
Let's Fire off the Little Dragon Trebuchet!

Put the projectile in the pouch and lower the arm of the trebuchet Run the strings and pouch along the bottom of the runway they should stretch out nice and flat. When you release your finger the arm will swing around and the ball will be thrown forward.
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. Here is a quicktime movie of the Trebuchet launching
Trebuchet launch (MOV apple quicktime)


Some Tips on making your Little Dragon Trebuchet launch even further
  • Put a heavier counterweight
  • Move the pivot pin in the swing arm closer to the counterweight. Remember you drilled three holes in the swing arm? This change in location has a big impact on arm swing speed.
  • Change the length of the string pouch. The longer the string the faster the projectile will go
  • Important: Change the angle of the nail on the end of the swing arm. This angle determines when in the swing the pouch is released. The sharper the angle the later in the swing the pouch is released. So if your projectile is going too high toward the ceiling make the angle of the nail sharper. If your projectle is going toward the ground too soon lessen the angle of the nail
  • Make the trebuchet swing arm skinnier and lighter by shaving it or using a thinner piece of wood
Remember to Paint your Trebuchet! It makes a big difference!
Some More Tips on Making it better:
  • The optimal weight ratio for counterweight and projectile is 133 to 1 so try to make your counterweight 133 times heavier than your projectile I have more info about weighing your counterweight here
  • Optimum distance is reached if the projectile releases between 40 and 45 degrees
  • A lighter projectile will go faster but not as far
  • Adjusting the hook forward will release later and cause it to go faster but not as far
  • Adding wheels will add more power! The wheels add more power because as the counterweight falls the whole machine moves forward slightly to "meet" the fall thus giving you a more vertical drop leading to more energy being transferred to the throwing arm.

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This is the finished and painted trebuchet. I hope you enjoyed this project! Bookmark This website and check back again I have more projects coming. I also have projects for dioramas and for video game making. Check the sidebar.

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Want to make an improvement to the Trebuchet? A web visitor has made this treb and he added a nice little design change so he can lock it in the ready to fire position. Pulling the pin fires it off. See his trebuchet and the design improvement here
external image johns-trebuchet6.jpgWant to make even more improvements? Another web visitor who is an engineering student did some research and made a treb that is even better. He has also given some great information about projectiles and weights. See his trebuchet and information here
credit goes to http://www.stormthecastle.com/trebuchet/trebuchet-build5.htm || || external image counterweight2.jpg ||