Toco's Knex Trebuchet




The easiest trebuchet ever! It isnt verry good compared to this Knex Desktop Trebuchet by Knexagon. The weight is the same.

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Step 1: Parts List

7 grey
4 red
3 blue
3 yellow
3 gray
4 blue (3 blue = 1 grey)
7 yellow
2 orange
3 grey end cap things
4 purple
4 blue
1 small gear

Step 2: Make the Arm

need the 2 orange connectors,1 grey rod,1 red rod,8 tires,1 grey connector.

Put the grey connector on the end of the red rod. Slid the tires on. Put an orange connector on the other end. Put the grey rod on the other end of the orange connector. Put another orange connector on the end of the grey rod.

Step 3: Make the Base

Make this.

Step 4: Put the Arm On

slide a red rod threw the bottom orange connector. Put grey end caps next to it. Put it on the top yellow connectors of the base.

Step 5: Extend the Base Ad Add the Trigger.

Put two grey rods on the back. Slid the spacers on the right grey rod. Cap those with yellow connectors. Put a yellow rod inbetween the yellow connectors. Now take a yellow connector on the right grey rod right after the spacers. Put a red rod tword the inside on the yellow connector and a blue one tword the outside.

Step 6: Make the Projectile

put a grey cap on a blue or white rod. Now put a small gear on the rod. Tie some string on the connector and a loop at the other end.

Step 7: Load and FIRE!

put the looped end of the projectile on the back side of the top orange connector of the arm. Pull down to the trigger. Back up

Step 8: Send Me Your Pics!!!

send me your pics!!!!!!!!!!!!!!!!!!!!!!!! I want to see your instructables in action.

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    33 Discussions


    6 years ago on Introduction

    What else could you shoot? The thing that you shoot is hard to make, so I was wondering if there is a normal knex pice(s) that you could shoot.

    just clearing this up for people who dont know about these they are pronounced treb-a-shay. not tre-ba-shet


    8 years ago on Introduction

    Now, a few years after I published this instructable i have tried to follow it and build the trebuchet. I failed miserably. I dont know what I did wrong because I followed the instructable exactly.


    9 years ago on Introduction

    HI Taco!
    Please post this on my forum!
    i need some people to help get it going!
    anyone can post on it

     I have created the ultimate Trebuchet after hours of playing and  messing with fisic  I came up with a trebuchet that is capable of going farther than ten or even fifteen feet. ofcourse i did have to add more than a few parts and rearrange them to make it the best. it's still 99% knex (1% is the rope) and I would love for you to see it and comment on it

    2 replies

    Reply 9 years ago on Introduction

    awsome! sorry it took me so long to reply. I havent really been on instructables lately. I have been buisy with a bike generator. I would love to see your trebuchet. Please post a video or an instructable!


    Reply 9 years ago on Introduction

    I dont remember if I ever replyed to you or if the sorry below was for you. I say just be creative. You could make a basket and fill it with heavy things. If you had like $20 in duck tape you could  wrap it around a knex rod. To be honest If you want to spend money on a catapult or trepuchet I would make one out of wood or metal with a spring or a weight that you could purchase at a science store or possibly a hardware store like menards, lows, or home depot.


    Reply 9 years ago on Introduction

     or you could use metal ring weights make them go through the knex rod then hold them together with the gray/purple clamps


    Reply 9 years ago on Introduction

    It has been over a year since I have even looked at this instructable. I looked at my video and you are very correct. The trigger is not really doing anything it really only slows down the trebuchet.


    10 years ago on Introduction

    Hey wafflicious I didnt design this!!! My friend did and I thought that it would make an ok first instructable. I rebuilt it and added your trigger. It is a much better trigger.


    10 years ago on Introduction

    in the video.. it looks like the trigger wasn't doing its job and holding down the thing... it looked like it went by it self / i made and the trigger isn't all to good though the thing all together is good. 3/5


    Reply 10 years ago on Introduction

    I feel like this doesn't even include any sort of sealant. the word you're looking for is cocked. (no middle school humor now, kids.)