Introduction: Huge Knex Crossbow

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of Making the Trigger Mechanism

these pictures are pretty easy to follow

Step 12: Rubber Band Instalation

Picture of Rubber Band Instalation

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

Step 13: Adding the Spindle Wheel

Picture of Adding the Spindle Wheel

add the spindal wheel

Step 14: Putting It All Together

Picture of Putting It All Together

refer to pictures

Step 15: Positioning the String

Picture of 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

Picture of Loading

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

Step 17: Modifications

Picture of 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


kevinandbelma (author)2016-02-17

love it!

Lowney (author)2009-09-23

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?

FFDPfanJL (author)Lowney2013-07-14

LOWNEY!!!! You are epic!!!

goaway (author)Lowney2011-07-11

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

KnexFreek (author)Lowney2009-09-24

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

Lowney (author)KnexFreek2009-09-24

Yeah I kinda wanted a more precise answer

KnexFreek (author)Lowney2009-09-25

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

Lowney (author)KnexFreek2009-09-26

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

KnexFreek (author)Lowney2009-09-26

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

Lowney (author)KnexFreek2009-09-26

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

MotaBoi (author)Lowney2009-11-17

 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!

The_lucky_sniper (author)2012-02-22

It looks cool, the one i made shoots reel arrows, they work really well! 8/10

kwibus24 (author)2011-12-21

cool crossbow!

szzxzzs (author)2011-11-13

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

szzxzzs (author)2011-11-11

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 ?

jefinger (author)2011-07-14

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

lvorstenbosch (author)jefinger2011-08-05

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

eproctor (author)jefinger2011-08-03

a small wheel is under the entire cbow

sukinmaru (author)2011-06-21

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

Football viking boy (author)2011-06-08

from 2007 wow

glugnar (author)2011-06-07

This thing looks sick, what is the range?

DJ Radio (author)2011-06-06

So it got featured this long after it was posted?

apples!!!!! (author)DJ Radio2011-06-06

Yes. Yes it did.

lul (author)2011-03-12

i build the crossbow nice but the trigger dot work i can klik te rod conetor on the wite conetor so if i wana shoot i need to hold the string

michiel1604 (author)2010-12-19

Hey, i want to make this awesome crossbow, but how far does it shoot, so i dont make this and discover it doesnt have any power at all

wiiking2015 (author)michiel16042011-02-13

what u cant just deal with what he tells u schultzy

mberg (author)2010-11-16

nice crossbow man!

superbestknex (author)mberg2010-11-24

its big

flyerminer (author)superbestknex2010-12-17

and the size of my car.

knexinventer (author)2010-08-13

i like it it is so fun

AnDrEwReNoLdS (author)2007-02-01

hey this gun so much fun and easy to build for the 12ft string I substituted it with fishing line

Mepain (author)AnDrEwReNoLdS2007-02-01

yeah, its best not to use weak string for anything i make, but rather to use something stronger.

yofatmama45 (author)Mepain2009-01-03

u r such a lire qith how many wheels u r using you need a aooltl of 7 wheeles why

??? use English!

i said "you are such a liar you only said 2 wheels in the pices list but you need 6+" Is that better Fyi i am getting a f in languae arts so that explains why dont u think

Terrible, extortionate grammar. f certainly.


Oblivitus (author)2008-07-24

Very nice crossbow. I rated it 4.5. However, if you did this it would make it even more powerful. (I edited the picture but hope that you get the general idea.)

Oblivitus (author)Oblivitus2008-07-25

Maybe I'm wrong but I still think that it's worth a shot.

dsman195276 (author)Oblivitus2008-10-13

the problem is that the bow would bend back as far as that. but just bend inward to the center wheels you put on. so the bow would travel less distance and have less power... and if you connected a wheel to the bow it would cause the bow to stop bowing out at the part before the wheel is hooked up...

Oblivitus (author)dsman1952762008-10-13

Hmmm, I made that comment a long time ago, I don't think it would work well anymore either.

MotaBoi (author)Oblivitus2009-11-17

what i did was extend the front a bit then attached elastics from there to the end of eac side of the bow.  it actually helps prevent it from snapping AND it doubles the range

dsman195276 (author)Oblivitus2008-10-13

ya, i was just looking through the comments this morning. that was a pretty good idea though. it would have been great if it worked. actually, if you mount another wheel farther down and make the string go from the wheel on the bow to the new wheel and then your wheel it could work.

Try connecting the wheel with string.

Oblivitus (author)dsman1952762008-10-13

Well, I was hoping he would try it, I don't want to.

stale56 (author)Oblivitus2008-11-25


SonicX 22 (author)2009-09-11

looks great as long as you don't put your finger on the trigger when your nearby someone 4.5*

grevious (author)2008-09-27

is it possible to remove any of the grey rods, i have a few (20+ im guesssing) but i would like to make this and it looks like a few could be removed from the body?

stale56 (author)grevious2008-11-23

dude i only have like 5 total grey rods

grevious (author)stale562008-11-25

im up to around 25 now lol.

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