Dominant Catapults!


Introduction: Dominant Catapults!

Running out of ideas?! Tired of egging your friends house and getting in trouble!! BUILD A CATATPULT!!!!! egg from a distance, saves energy and is a good time. Just a couple of easy steps you will be egging in no time ! We did this because it was project in physics class.

Step 1: Tools and Supplies

Make sure you have the proper tools and supplies in order to make your catapult. you will need wood, screws, drill, metal bar, springs, bracings, gatorade cap, wood cutter of sum sort, and paint if you would like to make it the color of your desire

Step 2: Combine

In step 3 you will cut oak wood into four parts. depending on how small or large you want your catapult to be. Our base was 57 cm by 60cm add wood bout the same length as the width for weight in the front as well as two long beams 122cm by 9cm by 5cm under the base for more weight. Cut three wood pieces into 57cm 8cm 5cm place them in the middle on opposite sides of each other they should be going vertical. But leave one alone its going to be the arm of your catapult.

Step 3: Drill

Drill three holes in the pieces you just cut make sure there all alighned up to each other. we used 1/4 in.  Also drill 2 1/8in holes on the inside of the base and 2 1/8in holes on diferent sides of the arm. The piece wit the hole in it alighned it with the holes than place the metal bar in the holes.Then put another wood piece bout the same size on top that will be the stopper to keep the arm from smashing allthe way down. In the rest of the holes put in metel hooks. Your almost done the hardest part, was putting the spring on both hooks.

Step 4: End Product

This is what your end product should look like. pretty nice if i do say so myself.

Step 5: Minor Adjustments

Go out and test fire your catapult a couple of times. our arm broke through the stop two times before we got the idea of screwing the metal brace on top.

Step 6: Firing Squad!

our catapult was the best in the class it launched a golf ball 46.9m and its arm accleration veloctiy was at 308m/s



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    17 Discussions

    If you put a sling rather than a cup on the catapult, you launch the projectile A TON farther than what you have been getting. And i mean A TON farther!

    Considering that several other persons have posted pretty much the same thing, this isn't very good. You've posted something that you did but not explained it very well. Other students have given more information on the build and data.


    12 replies

    Yes, a bit hasty in the publishing - maybe they were working to a deadline?
    I think these people should update their Instructables with the grades they got?


    I'm quite keen on the idea of using Instructables to document projects like this, something I am keen on doing when I move to High School.

    What the teacher should do, though, is;
    • Join.
    • Identify themselves.
    • Create a group for all the projects to go into; Blogger High School Group etc
    • Provide feedback on the projects here - such as posting the project grade in the project's comments.
    (and if the authors of this project read this comment, they should pass it on to their teacher.)

    I agree. Start with a forum topic. Maybe one person thought of putting theirs up, then the others joined-in and it wasn't officially organised?


    I gather from one of the other projects that they were told to publish like this.

    Not really - you can edit published projects as much as you like.  The authors could add an extra step to show off their grades.

    Your Instructable is pretty weak. I have to agree with the other users... Remember what I told you while we were in the computer lab?  "If you do a poor job putting this together, the Instructables community will tear it apart!"  I think these fellow below are going easy on you.

    1 reply

    So, are you their teacher?

    You're right, we are going easy, but mainly because we can see they have never attempted write-ups like this before.

    Maybe next time you do a project like this (are the rocket cars your as well?), you ought to set a homework that the teams should browse the site before they start the projects, so they can see how to write a good, maybe featurable project,