Hand Operated Trebuchet/tennis Ball Hurler/staff Sling

i wanted to build a trebuchet but i didnt have the materials for something like that

so i thought up this little thing that can fling a tennis ball over 100 feet

its half trebuchet and half atalatl (if you even know what an atalatl is :D)

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Step 1: Materials

1. 3 ft. Dowel rod that isnt too thick for your hands
2. Strong string (i used shoe lace)
3. Power drill with drill bit
4. Strong cloth stuff (i used old pair of pants, a shirt wouldnt work)
5. Metal clothes hanger
6. Key chain ring
7. Needle-Nose pliers (ones with wire cutter)
8. Gel type super glue (hot glue might work)
9. Scissors
10. Stapler
11. Tennis Balls

Step 2: Step One

Step one is to drill a hole in an end of your dowel rod about a one half to one inch deep.

Then take your needle nose pliers and cut out a piece of wire from your clothes hanger and glue it down into the hole with at least one inch of wire sticking out from the end of the hole.

Once your glue is set then angle the wire at the end of the dowel rod about 45 degrees.

Step 3: Step Two

The next thing to do is to get your cloth out and some scissors that will be able to cut it and cut out a rectangle 7 inches by 4

and then you should cut the corners off like i did in the picture

Step 4: Step Three

The next step is to poke holes in the corners of each side of the cloth and tie a little bit more than 2.5 feet (to compensate for knots, the more you have the more you have to tie knots with) to each hole.

Step 5: Step Four

This step is to tie your key chain ring to the end of one string securley.

Then tie the end of the other string to the dowel rod near the end.

NOTE: when you tie your knots make sure the lengths of string are equal when the ring is on the pin and the string is hanging down perpendicular to the dowel rod

Step 6: Tweaking and Firing

You will want to staple the pouch thing so that it can hold a ball better.

When you want to lauch the tennis ball the most simple and basic method to do it is just to hold the dowel rod with the tennis ball in the pouch and key chain ring on the pin on your shoulder and just swing like you would swing a sword trying to cut a water melon in half that is located above your head. and by that i mean you do not want to follow through all the way to the ground you want to stop probably 100 or so degrees from where it started. and there are other ways to do this you just need to think about it :D

And if the ball is either going straight up or too horizontal you will need to adjust the pin on the end of the dowel rod. and you might have to adjust the pin if you want to throw something heavier like a baseball. you should be able adjust it if your glue is strong enough

I will be posting a video on youtube of this in action and you will be able to see my and my friends method of flingin tennis balls. :D

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    14 Discussions

    I would like to note that these have existed for a very long time. When gunpowder was first utilized as a weapon, the staff sling was often used to hurl the resulting incendiary devices. I can't find much information about when the staff sling was first invented, but It features in several pieces of art dating back at least to the middle ages.

     I'm thinking a piece of bamboo, since I have no dowel rod which doesn't exist within more than a thousand kilometers around my place, and a wood screw which gives me a simpler version of that device (I don't know any other short way to describe it). Shoe laces are out of my reach so substitute with some hemp twine. The pouch would be just some spare pieces of cloth sewn together. I don't want to use key chain ring so I'm gonna substitute with some wire.

    In short I'm gonna make a simpler version of that device that provides leverage to fling a tennis ball (or similar) a hundred feet or more. 


    9 years ago on Introduction

    Fyi, i have one of these, i actually did a science fair project over it a while ago, i find that it can fling further if you tie (or attach with an eyehole screw) onto the pole around 3 inches away from the end. it will give you a little bit more distance, and a bit more control too!!


    9 years ago on Introduction

    atlatl:def primitive spear throwing device. isint being smart great! $;)


    Reply 10 years ago on Introduction

    if you liked this sling im probably gonna be making an instructable for a regular sling, just to let you know :D


    if you liked this instructable im gonna be making another instructable for just a regular sling, just to let you know :D