Introduction: Knex Rocket That Really Launches

Picture of Knex Rocket That Really Launches

This is a Knex rocket that actually launches using 4 large rubber bands. It is very simple and uses few pieces. It flies about 20 ft. Watch this video for proof. Please rate. Check out my new cannon.

Piece count (based on original colors)

red-28(n.b. mine are all green)

white snowflake-3
blue 3D-5
purple 3D-29
gray 1 slot-8
gray 2 slot-4

4 large rubber bands


Step 1: Rocket

Picture of Rocket

This is the projectile shot out of the base.

Step 2: Base

Picture of Base

The Rocket shoots out of this.

Step 3: Adding the Rubber Bands

Picture of Adding the Rubber Bands

You place each of the rubber bands around the white peg at the top. Then you add the rocket. Finally you pull down the rocket on to the rod and release it. Watch this cool video to see the launch.


Knex4Life23 (author)2013-01-22

i made it and it goes 60 feet in the air but i modified the structure

Airsoft 007 Sniper (author)2010-10-24

you could make the design better good try i guess

Airsoft 007 Sniper (author)2010-10-24

you should design a knex greanade

Airsoft 007 Sniper (author)2010-10-24

thanks for the help

Ps2playa (author)2010-02-15

i built this and i loved it so i thought i would improve it so i made a rocket three foot six and it didnt work but i made other big ones that were big and they worked

KnexFreek (author)2010-01-23


something94 (author)2009-08-07

could I possibly make it taller and tie rubberbands together to make it go higher? or would that make it collapse??

uguy (author)2008-07-23

Isn't this just a vertical catapult?

Kiteman (author)uguy2008-07-24

Maybe so, but aren't most K'Nex "guns" really just catapults as well? (Nice-build, number-boy.)

Jesus. (author)Kiteman2009-05-23

yes but mostly just cannons and snipers are catapults just so you know

DrWeird117 (author)Kiteman2009-02-07


The Jamalam (author)Kiteman2008-07-28

acctually, no they are not. they are crossbows to an extent. a catapult uses a slingshot mechanism or a swinging arm linked to a weight (trebuchet). Knex guns are crossbows, in that they use a blocker (trigger) to hold back a bolt which holds a projectile in front of it. when the trigger is pulled, the potential energy is released throwing the projectile forward.

Kiteman (author)The Jamalam2008-07-29


So the "block trigger" that certain K'NEXers moan about is simply something that blocks the movement of the projectile? I just learned something new about K'NEX...

However, true crossbow triggers retain the string, and the elastic PE in all bows (cross, long, compound and ballistae) is stored in the bending of the arms, nor the elasticity of the string (which is actually inelastic).

The Jamalam (author)Kiteman2008-07-29

Yes - that is a block trigger, and that is true...

And the only true crossbow on this website is the one by Mepain called huge knex crossbow.

Lukes mate1 (author)Kiteman2008-07-25

yes thay are so dont be so annoying uguy

Skreetsha (author)2008-08-25

did you know that you can put in the bischoff system so it can have a trigger :D

Jesus. (author)Skreetsha2009-05-23

or you could put the mec from the brickster LDS or i_a_c 's heavy cannon mec on it

what is that? Could you post pics of it.

Trainman 2001 (author)2008-07-23

built then turned it into a mortor 60FEET RANGE ON MINE!!!!!!!!

Speedmite (author)Trainman 20012009-04-29

Build a potato cannon. Beast, Ok one go at least 200 ft with anything that fits down a barrel. All you do is tip it at a slight angle to get a mortar.

Speedmite (author)Speedmite2009-04-29

The pic goes Mortar gun hotwiser

Wow. Could you possibly post pics so I can make mine that good.

no im sorry ill get a pic though

DrWeird117 (author)2009-02-07

Really cool.5*

Skreetsha (author)2008-09-08

oooh sorry but this comment was just a tip :S

bannana inventor (author)2008-07-27

Very original idea!!! 4.5!!! :D

Lukes mate1 (author)2008-07-24

this rockes and its an easy build

panzerunit5 (author)2008-07-22

lol i need to build it it looks realy cool on the vid. may be clearer on the instuctions but not bad

About This Instructable




Bio: I have moved on to better things...aka YouTube. So I will most likely not reply to any comments, sorry for any inconvienience. If you ... More »
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