Huge Knex Crossbow




Introduction: Huge Knex Crossbow

this is the biggest crossbow made out of knex that ive seen on this whole site!!!

Step 1: What You Will Need

other than the pieces in the pictures, you'll also need a 12-foot string- yes, you read right. 12 FEET!!

Step 2: Bow

1. the four basic pieces you will build.
2. these are the left and right halves of the bow.
3. &4. close-ups on the bow.
5. put the first wheel on.
6. put the second wheel on.

Step 3: Body: Front

1. build this piece
2. details
3. details
4. next build this, there are four layers
5. add a gray rod, but only one
6. two gray pieces attached to an orange connector
7. another one
8. yes, one more
9. have the orange connectors lined up like this
10. now put them together, but pay close attention to the way it is put together, as the side with only one gray rod needs to be on a certain side.
11. both grays on this side
12. this is te side with only one gray ro
13. add a gray rod on both sides
14. add another
15. finish it up

Step 4: Handle

1. what your building
2, 3, 4, & 5. build these
6. connect like this
7. turn to this position
8. add this piece
9. turn to this position
10. add this piece
11, 12, & 13. puting it together

Step 5: Track- Front Half

1. make two of these
2. one of these
3. there are 8 red things
the rest are blank because it would be pointless to explain then as they are easy to understand... for me, at least.

Step 6: Install the Track and Wheels

1. body & track
2. connect like this
3. connection complete
4. make these
5. the one on the bottom is finished (what it should look like)
6. slide the top one in
7. connection point #1
8. connection points #2 and #3
9. if this blue rod is sticking up,
10. then push them down like this
11-14. install wheels
15. complete

Step 7: Body: Back

1. the back of the body
2. the other end of the track is what you will be building next
3. first make this,
4. then these,
5. then this,
6. then these
7. now
8. put
9. it
10. all
11. together
12. like
13. this

Step 8: The Spindle Wheel, or Whatever It Is

these are some details of the wheel, you should be able to understand it

Step 9: The End of the Crossbow

1. the end of the crossbow
2. make these
3. put them together
4. then make two of these
5. now make two of these
6. form the piece in picture #3 into this
7. put these two pieces together
8. form the other piece in picture #3 into this
9. you've already made the piece in the upper left corner, so just make the others
10. now put these together, just like this
11. put these together
12. & 13. put it all together

Step 10: Installing the End of the Track

1. you'll put these together in this step
2. refer to picture
3. this is the connection point
4. pay attention to that black clip
5. do i really need an explanation for this?
6. connect to the black clip
7. " " " " "
8. put the green connector in between the two gray rods

Step 11: Making the Trigger Mechanism

these pictures are pretty easy to follow

Step 12: Rubber Band Instalation

this crossbow uses the same rubber bands as my small gun.

Step 13: Adding the Spindle Wheel

add the spindal wheel

Step 14: Putting It All Together

refer to pictures

Step 15: Positioning the String

this is kind of hard to follow, so if you're confused, refer to the last picture, whitch shows the path of the string

Step 16: Loading

self-explanetory, but i also have a video for it.

Step 17: Modifications

this step is for modifications that i found out about after i posted the gun.
1.addition to trigger
2.this makes the end of the trigger mechanism less flimsy

Be the First to Share


    • Cheese Challenge

      Cheese Challenge
    • Plywood Contest

      Plywood Contest
    • Fried Food Challenge

      Fried Food Challenge



    13 years ago on Introduction

    Can anyone tell me how far this shoots? I'm making my own repeating crossbow but I don't know whether to make it true (like this) or use elastics. I take it elastics shoot further but how much further?


    Reply 11 years ago on Introduction

    9.7% increase in firing rang from a stop (aka distance when not moving) a 14.3% increase in distance when forward movement is taking place but 14.3% is depending on how fast you can run. a 1.6% decrease in prosition targeting (aka how acurite it is) when elastic(s) are used
    oh and great gun it looks awsom


    Reply 13 years ago on Introduction

    im thinking 100+ cause its made by mepain but probably goes further


    Reply 13 years ago on Introduction

    Yeah I kinda wanted a more precise answer


    Reply 13 years ago on Introduction

    well i was just trying to help :( next time i will say nothing at all :(


    Reply 13 years ago on Introduction

    I just wanted to know whether to use a tension beam (this) or just a slingshot.


    Reply 13 years ago on Introduction

    it looks to be tension beam b/c of how much the bowis bending, the rubberbands are tied in a loop, and the placment of the front of the rubberband


    Reply 13 years ago on Introduction

    I think I'm going to make my repeating crossbow true, like this, not a cannon, like most of the 'crossbows' on this site.


    Reply 12 years ago on Introduction

     if made this i actually does shoot that far becasue it uses tension and the tension in the gray rods really suck!  It only shoots about 10 ft but its still really cool!


    10 years ago on Introduction

    ah ok i have update the trigger, it is now a better trigger and he is saver but the crossbow is not very powerfuel. and the bow will breake often its a good design but not powerfuel
    xD 3.0


    10 years ago on Introduction

    hey it is a reale cool crossbow i have build it but the trigger is not working can u help me with a video how the trigger working pls ?


    11 years ago on Step 8

    I'm having issues figuring out how the string is attached can anyone help me out with this?


    Reply 11 years ago on Step 8

    the first hubcap on the right holds the string, by putting it onto the string


    Reply 11 years ago on Introduction

    a small wheel is under the entire cbow


    11 years ago on Introduction

    I thought I could build it, then I glanced at the pile of grey rods needed. Still looks wicked, what range does it have?