Spring Catapult Pen

Intro: Spring Catapult Pen

So, in this Instructable we are going to learn how to make a spring catapult (probably not the correct name fore it) out of old and unusable pens.

NOTE: ALL PENS ARE DIFFRENT, you will need to adjust and modifie this instrucable to fit your pen, and will take a couple of tries to get the most power out of the spring.

Step 1: Parts Needed

All of the parts that you will need to this project you should already have :

- a couple of spring loaded pens, the ones that you click on to open ( you will only need one but not all pens work so you will need to experiment with a few)

- Some tape, I used some electrical but ducktape will work fine

-scissors / dremel with cutting tool...

-Optional ball point pen

Note: As you can see, most of my pens aren't in working condition as I have a habit of taking them appart when I'm bored. So I'm not totally sure which part comes from which pen.

Step 2: Taking Appart Then Pens

Now we are going to take appart our pens and finding every part that we will need.

Firstly we are looking for a spring pen with a "long" bottom section with lost of room inside for the spring ( see picture). Ideally you want 75% of the spring in the pen and 25% out when it's touching the bottom of the pen with no force applied.

You are also going to need the spacer thing (see picture again) and most importantly the spring fro the pen.

Next we are going to need the end cap off a ball point. This is optional as it is our ammo and if you can find something els that fits nicely it will work fine.

Step 3: Preparing Ammo

For the ammo you will need the tape, the spacer from the pen and the end cap

Begin by wrapping the tape around the end cap until it fits VERY SNUGGLY in to the bottom of the pen.

Then cut down the sides of the exes tape and push them into the middle of the end stop ( you might need to trim off some of the tape)

Continue by cutting of some of the spacer allowing more room for the spring later on.

Finally jam the thin side of the spacer into the end stop. this prevents the tape from peeling of when inserting into the barrel.

Step 4: Thank You

I would like to thank you for reading this instuctable. If there are any question or any advise ( as this is my first intractable) please leave it in the comment section.

If you liked this project, give it a vote for the reuse contest.



P.S. do not shoot this at anyone as it is extremely hard to aim and might go into someones eye.



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    5 Discussions


    3 years ago

    I seem to be missing the last step :/ I'll try to correct the spelling and ad the ending sometime this week


    3 years ago

    Yeah my spelling isn't great, I'm not used to writing in English ;)


    3 years ago

    Well done!


    3 years ago

    Very cool but try to spell correctly and one day you'll get your project featured