Big Powerful Knex Crossbow





Introduction: Big Powerful Knex Crossbow

About: I seem to like building crossbow shaped objects.

I've made a cool crossbow that can fire +-150 feet.
It doesn't have a trigger like the other ones because i found out that you can't use the full power of the crossbow then.
It uses the wheels to spread the power across the rubber bands to make it shoot further.

I recently joined and therefore this is my first Instructable and i've tried to make it as detailed as possible.(I'm trying to make a new trigger very soon)

Finally after like 2 years I made a proper trigger xD. It is buildable from the pictures in this topic:

Step 1: Pieces List.

You will also need 1 red connector and 1 red rod extra for the arrow.

Step 2: Building the Handle.

Pic 1: Just build these two things.
Pic 2: Put the blue rods in between every gap.
Pic3: same

Step 3: Building the Bow.

Pic 1: Make these bottom pieces.
Pic 2: Build these top pieces.
Pic 3: Add the rods to the bottom pieces.
Pic 4: The same as pic 3.
Pic 5: These are the top pieces upside down with the yellow rods, just add yellow rods.
Pic 6: Combine the top and bottom ones just like on the pic.(Don't connect the yellow rods to the bottom pieces, just leave em.
Pic 7: Add the 4 red rods.
Pic 8: Add the 4 red connectors.
Pic 9: Add the pieces.
Pic10: Add this.(Don't forget the dark grey connectors at the back and the orange ones with black clips.)

Step 4: Adding the Handle to the Bow.

Pic 1: Just add it like this pic.

Step 5: Adding the Rest of the Bow.

Pic 1: Put these parts on the yellow rods on both sides.
Pic 2: Add the extra rods.
Pic 3: Do this on both sides.

Step 6: Adding the Rubberbands

Pic 1: Connect the rubberbands like this.
Pic 2: And so forth.
Pic 3: You the 5 rubberbands to be like this.
Pic 4: Get the red connector off it and put the first of the chain rubberbands around it.
Pic 5: Go all the way around and do the same thing on the other side, then put the rubberbands over the wheels.

Now you're ready to load!

Step 7: Loading the Arrows.

Pic 1: It fires this.
Pic 2: Load it like this.

Just pull it all the way back and shoot.
(Don't shoot any siblings with this...)

If you want to keep your red connectors don't fire straight into a wall.
(See Pic 3...)



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    This is one badass crossbow but can you try to figure out how to make the arrow wind resistent. Going to make the v2 trigger

    This crossbow is amazing!!!!!! You'd think it would fly anywhere but strait... so I did somethin stupid n shot it inside, lets just say theres a dent in my wall noone knows about...

    it looks like (good thing)

    Trigger added to instructable:

    I love your X-Bow! I built it and it worked great! I decided to add a real trigger system and it really works well. Now I can fire with a hit of a trigger. Thanks again so much for the bow! 5*! One of the best and fastest. 'IF' you want, I could post a pic of it with the trigger and handle or a video. I_AM_CANADIAN, I kind of used your AST handle idea... Is it ok if I did? 'Cause it's a great handle but the trigger system I made on my own. Once again, I could post a video or pictures with the handle and trigger system. I also modded a couple of things like: adding more wheels, making the aesthetics better, and making it more comfortable. So that's all. NICE BOW! (once again.) bye!

    5 replies

    Yeah its a nice weapon, but looking back on it, it has many points that could've been built better.
    I am interested in the trigger though, how does it work?
    The only system I used is the one from the Reaper/Blockhead, which has 1 downside; massive amount of friction.

    Very enthusiastic comment btw ^^

    Haha! Yeah, I know it was :D. I can post some pics showing how it works. Well first off, it has a trigger. The trigger is connected to a green small rod which is connected to a blue and black joint (that moves like your knees) then to a orange connector, then to a black small y shaped connector piece. The back end of the ammo clips on the black y clip. When the trigger is pulled down, the black clip is moved downwards forcing the ammo to pop off and get propelled forwards. That's all.

    I could post a video if you like but I don't know where to. Can you post videos on this site? Haha, nevermind. I found the "video" button just now XD. I'll add it on YouTube.

    Could you PLEASE post what you have adjusted on your V2 version of this gun. It looks much better and sturdier. That would be AWESOME!

    So here's the video of how my trigger system works. (BTW I got this system from a rifle someone made on this site. I don't remember who. But when you see the system, can you tell me who made it? Thanks!)

    Hmm never tried that type of trigger, although it doesn't seem to hold massive amounts of power, it fits perfectly on this xbow =o

    Yeah I know. It's perfect for this bow. What do you mean by "friction" is happening with your block head trigger system? Is it rubbing against the walls too much or something? Hmm. I haven't built your blockhead and I brobably won't be able to since your V2 that I built just BARELY used up all my parts. I have lots of extra left but for example, I don't have any yellows connectors left and green rods and red rods.

    This is the part which caused the friction, which is a vital part of the trigger as it holds an arrow by its gray connector;using a rod through one of the white connectors. I did make progress yesterday solving that issue, while still having a working trigger. Also I got rid of that nasty exotic hinge piece(pic2)

    100_4859 (Large).JPG100_4867 (Large).JPG

    Thanks for showing this! It's awesome! Works really well.

    hallo nederlanders uuuhm hoe ver schiet dat ding want ik heb geen zin in zo'n klote ding dat 4 meter ver schiet want ik heb namelijk een zogenaamde semiauto gun gemaakt en die deed het niet eens XD en hoe land doe je erover om het te bouwen op een schaal van 1 to 10 hoe moeilijk well english guys i understand u guys dont know what im saying so same story in ure language how hard it is to build on a scale from 1 till 10 and how far do's it shoot sorry if my english is bad

    1 reply

    Minstens 60 meter, ik zou het dus proberen op een voetbalveld ofzo. Het bouwen duurt opzich maar 1 tot 1,5 uur, ligt eraan hoe snel je bouwt. Bij deze zou ik alleen wel aanraden geen trigger te gebruiken, want hij schiet verder zonder. English: It fires at least 60 meters, I would try firing it on a soccer field. The building process only takes 1 to 1,5 hours, depending on how fast you build. I would strongly advise not to use a trigger, because this reduces its firing range.

    i tried using the red rod with a tan connecter and it worked better

    man i know its been a while scince you made this but i got bored and made this, it was sweet i took it outside in the morning and i didnt even bother trying to get the arrow back cus it went to far! i love this more than my pistol or machine gun, thanks!

    You hook the red connector on the arrow to the rubberband, pull back and let go.

    do you need to pull the bullet behind with your hands or is it with a trigger?

    1 reply

    This one was meant to be used without trigger, the trigger addon does work, but as well as it should.