Knex Crossbow (yes Another One)




Hey guys, heres another Knex crossbow. Very simple (always the same thing) and very strong. Does have the look of a crossbow but maybe a bit bigger. Trigger system by me, incredibly effective even with strong rubber bands. You'll need a lot of blue rods (the ones who are between the golden and black rods (i got them from a huge crane in the Lost Mines set) ) , golden rods and purple connectors. I didn't tried to shoot through paper but i can see the mark in the wall when I'm shooting at 10'. Simple and stable ammo. Have fun Knex'ing.

PS. I broke 4 of my golden connectors when firing them.

PS2. I repeat myself a lot. So you will know what I'm talking about in a few steps because it's confusing a bit.

PS3. I used a black connector with 2 green rods to simulate a blue rod because I don't have enough.

PS4. If you want to start a flame war, visit 4chan or youtube.

Step 1: Get the Pieces

Here is what you will need.

2x Beige
10x Light Grey
3x Red
114x Purple
4 x Golden
46x Blue
11x Black

21x Green
2x Black (smalls)
138x Blue
72x Golden
2x Red
5x Grey

22x Blue Spacers
Some time to kill

1x Grey rod
1x Red Connector
1x Golden Connector

Step 2: Trigger (back of X-Bow Too)

Now we'll start by the end of the X-Bow. That includes the trigger and the rubber band release mechanism (who holds the ammo centered too)

Pic 1. Overview
Pic 2. Close up (cocked and loaded)


22x Blue Connector
4x Golden Connector
10x Light Grey Connector
3x Red Connector
2x Purple Connector
11x Black Connector

22x Blue Spacers
21x Green Rod
2x Black Rod
7x Blue Rod
3x Golden Rod
2x Red Rod
1x Grey Rod

Pic 3.What to insert on a Red Rod (in order from left to right if the arms of the X-Bow are away from you) :

-Light Grey Connector (clipped)
-Golden Connector (inserted)
-Blue spacers (6x) (inserted)
-Beige Connector (pin pointing right) (clipped)
-Black Connector (with pin of Beige Connector in it) (inserted)
-Blue spacers (2x) (inserted)
-Black Connector (with pin of next piece in it) (inserted)
-Beige Connector (pin pointing left, in Black Connector) (clipped)
-Blue Spacers (6x) (inserted)
-Golden Connector (inserted)
-Light Grey Connector (clipped)

Then add the blue balls (formed of 2 blue connectors clipped in) with some green rods. See pic. 4 and 5 for completed assembly

Pic 6. Rubber Band releaser blocker

1) What to insert on a Red Rod (in order from left to right if the arms of the X-Bow are away from you) :

-Light Grey Connector (clipped)
-Golden Connector (inserted)
-Blue Spacer (2x) (inserted)
-Black Connector (3x) (clipped)
-Black Connector (90 degrees to the left of the prev. Black Connectors if you turn the piece Counter-Clockwise) (clipped)
-Blue Spacer (2x) (inserted)
-Black Connector (same angle as last one) (clipped)
-Black Connector (3x) (same angle as the first ones) (clipped)
-Blue Spacer (2x) (inserted)
-Golden Connector (inserted)
-Light Grey Connector (clipped)

Done. Your piece is SYMETRIC.
Pic 7: Alignement of the black connectors. As you see, the 6 black ones points down and the 2 others point to the left.
Pic 8. Build that on both sides.

Pic 9.What to insert on a Golden Rod (in order from left to right)
-Blue Spacer (2x) (inserted)
-Light Grey Connector (inserted)
-Blue Spacer (2x) (inserted)

NB. Grey Connector is centered on the golden rod.

3) Clip the part from step #2 on piece of step #1 on the 6 black connectors (opposite slot of the red rod)

4) What to insert on a Black Rod (small one)
-Red Connector (3x) (clipped) (dont clip in the center slot)

5) Now take the part from step 4 and clip a Black Rod in it (not in the center again)

6) Clip a Green Rod in a remaining slot (on the sides, not in the center) of the part in step 5.

7) What to insert on a Grey Rod (from left to right, in order)
-Piece of step 6 (in 1 of the 2 slots remaining, but not in the center)
-Light Grey Connector (2x) (insert the greed rod from last piece (red thing) in the holes of those 2 Light Grey Connectors so the red piece cant rotate without the grey rod)
-Black Connector (on that youll clip 2x Green Rods (opposite slots) and a Golden Rod (if green rods are 1 to the left and 1 to the right, top slot)
-Light Grey Connector (insert Golden Rod from the Black Connector in the hole of that Light Grey Connector, so finally the red piece cant rotate without the Black Connector)

8) Clip the piece from step 7 in the Light Grey Connector from step #2.

Note : Add pic 10 to the bottom of the whole block.
Note 2. Now if you move the trigger, you should see the black connectors grabbing the others 2 on the top so they block them.

Step 3: Main Body

Here we will build the main body.

Pic 1. Overview
Pic 2. Build 4 of those and connect them using blue rods and golden rods. Build 2 of them using Blue Connector + Purple Connector instead of Purple + Purple.
Pic 3. Different view of pic 2.
Pic 4. Add 4 golden rods and 4 grey rods like this. That will keep the arms straight and strong.
Pic 5. You will need to remove 2 blue rods because the trigger will go there.

Step 4: Arms

Here's the arms.

Pic 1. Overview

Its the same thing as the body. Exept more blue + purple connectors to clip the stabilizers. That part HAVE to be strong or it will explode (i know what I'm talking about).

You should be able to build it with 1 picture.

Total 12 blue + purple connectors.

Step 5: Final Step.


Pic 1. Body + Arms
Pic 2. Body + Trigger Block
Pic 3. Trigger + Body

and your done. Now Cock that monster, put some ammo and pull the trigger. (don't try on yourself, i did and it hurts)

Step 6: Add-On : Rail

I took that idea from a crossbow that i saw on this site but didn't searched for it. I modified to fit on my crossbow and it works very well. Result : Accuracy +++ but you have to shoot smaller ammo (have to fit in rail). I recommand it.

You'll need :
- -9 (yes, minus 9) golden rods
-17 x3 golden connectors +1 for bottom of the rail
-17x3 green rods
- all the blue rods and you will remove to fit in the rail
-9 black rods
- i used 2 purples conectors but if you have green ones (without the pin to connect 2 purple connectors together) use them, the elastic wont jump and you will keep all the strength.

Look at the pics to build it, simple as saying Knex.

Edit : To build rail, look at . I used golden connectors instead of orange because i have a heavy lack of orange connectors.



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    33 Discussions

    one of my favorite and one of the best crossbows ever but the trigger is weird but i figured it out nice t crossbow 5.0

    1 reply

    Reply 8 years ago on Introduction

    Haha, Thank you very much! The trigger is the strongest one I ever saw, so you can build up a lot of tension without breaking the trigger. The bad thing is with tension, with purple-purple connectors will disassemble... but Thank you again for your comment :-)


    10 years ago on Introduction

    Only just found this..for some odd reason =/
    I think the connectors at the front should be yellow ones, the 5 slot ones, as the purple ones tend to split apart under strain.

    1 reply

    Reply 9 years ago on Introduction

    I don't see how you could place yellow / golden connectors in the front, since you can't attach them with the rest... Can you explain please?


    10 years ago on Introduction

    can you hlep me i need a gun fast now so can you make me a gun tell me what it is called so i can make it to shoot at my brother

    1 reply

    Reply 10 years ago on Introduction

    Hi there, Please add punctuation and correct your mistypes. I will then consider your request :-) Have a nice day! Tip : There's a "Check Spelling" button at the left of the "Post comment" button. You can also download Mozilla Firefox 3 with the Google Tool bar which will automatically underline your mistakes!


    10 years ago on Introduction

    Looks like a big T. now all you need is a I, n, s, r, u, c, t, a, b, l, e, and a s and then you have a big 3d INSTRUCTABLES!


    Reply 10 years ago on Introduction

    It's your choice, but you can put powerful rubberbands on this to get incredible power. Bad point = it takes many pieces to build it and it's not the best looking crossbow. If you want power, destruction and stuff, build it and have fun :-)<br/>


    Reply 10 years ago on Introduction

    I have enough to make it trust me if I have enough to make 6 drummer ian crossbows and enough for two 23 yellow long barrel sr-v1's im set


    Reply 10 years ago on Introduction

    Cool! Build it then, and please give me feedback. If you need help or anything just ask for it.


    Reply 10 years ago on Introduction

    O yeah i made this a while ago... I found that the trigger system / trigger was a little ackward so i changed it but overall I love that this gun doesnt use any Greens and is like... basically a big crossbow... I put three rubberbands on like yours type 64 and it launched the arrow.. knex rod bullet whatever projectile... from my garage to the neighbor's yard across the street and I hit their window....

    Good thing it didnt crack! I woulda been screwed.. and good think they weren't home.... from my house to the neighbors window is about .... im guessing here... 120 ~ ish feet cause i shot it like on the drive way.../ in the garage hoping to hit a tree 50ft ish away.... =) Great gun... Its easy to make it more powerful by just making a bigger frame =)


    Reply 10 years ago on Introduction

    Could you post pictures of your new trigger system please? I'd like to see how you changed it


    Reply 10 years ago on Introduction

    All I did was just make the trigger a little closer to the end so that I could fire it (by end I mean where the rubberbands go ... just like a little in front...) All i did was move it back a little thats all... btw if you read my forums you'd know that I shot my cameras' first camera was destroyed by oodalumps cannon misfiring, my second cheap... camera was destroyed by my prototype gun which had terrible accuracy but now is changed... so that it has more accuracy...