Introduction: Sypran's Knex Ballista

Picture of Sypran's Knex Ballista

Ok this is my first instructable, it is a cross bow with a new bow system (at this curent time) i hope u like it.

Ok for this pic you can see it has no trigger, that's because in not good at makeing trigers, well for crossbows anyway...

I don't know the range of it for i use weak rbs do to all my good 1s r ether :under something, destroyed by my cat, or put somewhere without me knowing... Ok anyway i used 2 hairbands on the limbs and they work really good, for me it fires 30ft before it hits something (this is with my ammo that i made, last step shows the ammo and how to make it)

Step 1: The Stock Pt 1

Picture of The Stock Pt 1

this is rather easy

7 blue rods
9 yellow conecters
1 grey connecter

(note that the blue behind the yellow is in middle connection thing not the hole except the 1 near my hand thats in the diagonal 1)

Step 2: Back Wheel

Picture of Back Wheel

the back wheel is not important, (the wheel its self everything else I think is)

5 orange conectors
2 red rods
2 gray conectors
1 small wheel
1 blue rod

Step 3: The Crossbow Limbs

Picture of The Crossbow Limbs

ok this is the crossbow limbs, of course you goto build 2

12 white/silver rods
4 white conectors
8 orange conectors
2 grey conectors
2 green/black rods

Step 4: The Top

Picture of The Top

OK this is going to be the top for the crossbow/ balista

14 grey connectors
1 yellow rod
4 yellow conectors
1 red rod
1 black idk what to call but its half connector half rod
2 green/ black rods

Step 5: Botten of the Bow Part

Picture of Botten of the Bow Part

the bottom of this bow

1 yellow rod
5 yellow conectors
1 red rod
10 grey conectors
2 green/ black rods
2 half rod half connector things

Step 6: The Conection Point of Stock

Picture of The Conection Point of Stock

this will be later used to connect the bow part to the ending stock

2 yellow rods
4 green/black rods
4 blue circle things
4 yellow connectors

Step 7: Peices Ull Need Later

Picture of Peices Ull Need Later

ya these you will need a bit later.

Step 8: Step 1+2 Conected

Picture of Step 1+2 Conected

simple connection between step 1 and 2 you'll do on both sides

Step 9: Step 6+ Step 8

Picture of Step 6+ Step 8

OK there is 4 added pieces the wheel is on the other side

2 yellow con
2 green/blk rods

Step 10: Add to Top and Botem and Mix

Picture of Add to Top and Botem and Mix

its a small addition to the top part of the bow
*plz note the 2 yellow connectors in the back are not supposed be in this pic1*

pic 2 is how the bottom should look

pic 3 is when u add limb then mix

pic 4 is just the top and bottem mixed

also note that after you are done add a red piece like in pic 3 unless you want the bow to break constantly

pic 4 is that 4 orange conectors and 2 green rods u built a wile back connected to the middle red rod

Step 11: Stock Con to Bow

Picture of Stock Con to Bow

ok now you will start some conections from the stock to the bow itself (yay finaly)

pic 1 this thing will keep the stock straight if some weight is put on it

pic 2 this is the first conections between the bow and the stock

pic 3 the top red peice realy dose not need the half rod peice but its there in case 1 falls off and i cant find it i have spares, then there is the yellow conector with 2 green rods on bolth sides

pic 4 this is optional, you can also take a red rod and put normal small wheels in this place to

Step 12: Stringing for Power

Picture of Stringing for Power

ok now this will show you my sugestions for stringing it

pic 1: the bowstring should be a stretchy not the strongest of all rubber band

pic 2: this is were i used hairbands but try to use semi string bands here also note the band in the wheel of the limb that should be a strong band

pic 3: also you can put the rubber bands like this to keep the bow from bending down

Step 13: My Kind of Arrow

Picture of My Kind of Arrow

ok you are done with the bow now what? easy you make arrows!

basicly what this is is a 10 inch wooded skewer with a notch on the end and tape for feathers and tape neer the tip to add some weight on the front so it gose head down first

you might want to skip the notch for it is kind of hard but it dose not mater

ok to load it (srry dont hove a pic) you place the arrow inbetween the limb wheels and pull back all you can before the end of the orange conectors going inbetween

ty for reading this, this was brought to you by: sypran, 5 times internet not responding, 2 computer shutdowns, 3 cans of seltzer, my old cellphone and 1 crossbow

Can you believe these photos were taken by a cellphone?


krwchampion2 (author)2013-07-21

again its a y clip

Sypran (author)2007-07-03

ok idk y but it wont show my pic on step 10 so gust foloow what i said there

smidge147 (author)Sypran2007-07-03

u may not believe me but i made up "idk" lol

will123 (author)smidge1472010-11-02

just to let u know u did so NOT make up idk

smidge147 (author)smidge1472007-07-05

i did cus one day i was sayin "i dont know to people on msn" and i got lazy of sayin it like that so i made it idk!

djhouse316 (author)smidge1472007-07-26

stop making up stuff

smidge147 (author)djhouse3162007-07-26

dude seriously i made it up!i created idk

King_Banana (author)smidge1472009-01-18

i seriously think i made up tyvm (thank you very much)

DrWeird117 (author)smidge1472008-10-11

Maybe you did for Instructables, but I heard it first like 15 years ago.

yerjoking (author)smidge1472008-05-28

i heard idk before i had an instructables account and before i found this website

yeah right that has been around for a long time.LOL

Oblivitus (author)smidge1472008-07-16

I'm gullible, I'll believe you.

F I S H (author)Oblivitus2008-08-26


Zenosythe (author)smidge1472008-06-02

oh, yeah?!? well I made lol LOL, NOT

captianchase (author)smidge1472007-07-05

i highly doubt that but whatever

will123 (author)2010-10-27

you need bettr pictures

Sypran (author)will1232010-10-28

I probably do, these are old and from my old cellphone...

atheas (author)2010-02-15

i found tht its good to but another piece of a skewer on the back for the notch

KnexFreek (author)2009-11-30

 is there a trigger

Sypran (author)KnexFreek2009-12-01

sadly no... I did make one once but it hardly worked and was to sensitive

ant ant 33 (author)2009-10-09

that thing you said you dont know what to call are called y clips just so u know

buthead187 (author)2009-10-08

lol you forgot the 1 blue rod

Sypran (author)buthead1872009-10-09

oops lol well ty for telling

allpinstripes42 (author)2009-08-30

I built this and I launch the long gray or black rod probably 50 feet!

mettaurlover (author)2009-08-27

now to make one of these that's twice the size of IAC's heavy cannon, switch to spears for ammo, and TAKE OVER THE WORLD! or at least the block i live on...

Sypran (author)mettaurlover2009-08-28

lol, I wanted to do something like that for my schools science club, but it had to be a catapult, no ballistas alowed

10110010R (author)2009-04-13

Dude this has been one of the most strongest knex guns i hav ever made man u need to give urself a big pat on the back when i shot it the ammo put a hole in my wall and is still stuck in there

Pbyrd (author)2009-03-19

I added a crude trigger to mine so I could hold it and fire it.

DrWeird117 (author)2008-10-11


Sypran (author)DrWeird1172008-10-11

umm you take the bolt out it through the front. hold the ruberband and the bolt, oull back then realese...

bounty1012 (author)2008-07-25

man you need some better pictures

Sypran (author)bounty10122008-07-25

i know.. ill update soon, (this was all taken from my cheap cellphone cammera) ill update it before the 27th

bounty1012 (author)Sypran2008-07-25


Sypran (author)bounty10122008-07-28

sorry that i could not update, i did not realise that i was going away from home for vacation. as soon as i can get my hands on some knex (i hope my uncle still has some) ill get pictures

bounty1012 (author)Sypran2008-07-30

thats fine i can wait

lodefreak (author)2008-03-08

nice,but actualy it's not a crossbow but a ballista

pls (author)lodefreak2008-04-16


rde (author)2008-01-02

i made it.

smidge147 (author)2007-07-30

its a movie not an episode.

cstrike pwner (author)smidge1472007-10-03

that episode WAS a movie, well you buy it as one.

Sypran (author)2007-09-02

my second instructable is up and is in time for use in school, an airplane that drops a knex rod, pencil, pen as a bomb!

knex hater hater (author)2007-07-03

when im done building im gonna post pics,itll be up at the least time,by tommorow if i dont have any after summerschool stuff. Ill garentee youll love this ballista even sheeeeezzzyyyy.

summerschool??? or do you just mean like summer camp?

summer school,it sucks but i get to play the guitar for one of my classes,but i gotta do algebra for the other. i get out like 12:30 western pacific time, but im usualy home like about an hour after that cause i got so much crap to do.

hahahaha im at the same time zone and my summerskools 1 hour and a half and i get out at 11:15 but no guitar :(

hahhaa,i take flash and guitar classfor summer school.

buterSBob29 (author)2007-07-08

Dude this looks like it could be a dragster

knex gunman (author)2007-07-05

click here to find out morecool it is a torsion catapult (aka balista). i was working on one but never had the time to finish it

skaterwhoowns (author)2007-07-02

looks like the bow off of God of War.

Sypran (author)skaterwhoowns2007-07-02

i nvr played the god of war games (dont got ps2 i got wii) but this is based off acient greek and roman balistas so thats probably y it looks like god of war bow

About This Instructable




Bio: My life is 3 things Engineering,Music,and Movies Life would bore me otherwise I want to do more Fun things yet i cant because ... More »
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