Professional water rocket guide

This Instructable will show you the how to build and fly water rockets. Featuring two stage rockets and drop away boosters, and also some basics.
This instructable is based on my knowledge of water rockets, that I have learn in the past few years.

I am not responsible for any damage you infict on your self or others from launching or building water rockets

Have fun building and flying!
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Step 1: Lets get Started

Picture of Lets get Started
A water rocket is propelled by pressurised air forcing water down though a nozzle. This creates thrust.

If you took a standard two litre fizzy soft drink bottle and pressurised it to120 psi the rocket would reach about 100 or so feet.

But then if you took 2, two litres bottles and pressurised it to 120 psi again the rocket would go about 150 feet or so because the rocket has more air in it therefore creating more thrust. The rocket will only go 50 feet more because of the added mass. You can stop this by making a two stage rocket. A two stage rocket will work better because it would not have to carry the full payload on all of its flight.

Step 2: How to build a fins and nose cones

Picture of How to build a fins and nose cones
In the next few steps you will be shown how to build the basic needs of a bottle rocket.
This step is to get to grips on what a rocket needs.

Step 1: nose cone

cut the top and bottom off a 1.25 litre bottle. Then cut the neck off the top.

Step 3: Step 2: Nose cone

Picture of Step 2: Nose cone
Step 2:

Cut a ping pong ball in half with a craft knife,
Then glue half of the ping pong ball into the top of the 1.25 litre bottle 'top'.

Use a Plastic adhesive glue, Or if apperance doesn't matter you could just tape it on!

Step 4: Step 3: Nosecone

Picture of step 3: Nosecone
Glue or tape the nose cone to the top of the rocket.

Adding wieght to the nose cone may help, It will move the centre of gravity higher, thus being more stable.

that looks intense

but cool

Talal Aziz2 months ago

i cant understand how the parachute will open ???

DOWNESJE1 year ago
cool rocket
firezone4 years ago
do you actually own the copyright to these diagrams, i highly doubt you have gone through what is needed to have the copyright for them and putting that little "copyright OscarThompson" in your pictures doesn't actually do anything
don't be mean to the person it is a good rocket
Everything is copywright from the moment someone comes up with it he is just saying they are his or someone elses
He is just putting acknowledgment that it is his.
Ian01 firezone4 years ago
I'm pretty sure you get copyright automatically, even if you don't claim it.
oscarthompson (author)  firezone4 years ago
I have only put it in so people can't use my pictures, unless they want my name on it. The my pictures as i drew them on paint, it really doesn't matter too much that i havn't copyrighted them.


paulmtchj1 year ago
hello oscarthompson could i plz have ur email because i have a few questions on specific aspects of the project :) thank you
I use small sections of threaded lamp rod for my water rockets, but I don't know about oscarthompson.
nice project do you have a video of it flying i wana see how it fly's so i know if it worth making
RGalliath2 years ago
Adding weight in the nose cone will shift the center of gravity up making more unstable and more likely to tip over in flight
except that you are wrong. think of the difference between throwing a cottonball and throwing a marble the same size. there is the same air resistance on each, but the marble goes further because it has more inertia and is better at penetrating the air because it is heavier. now think of an arrow. there is weight on the tip, so that it flies straight because there is more drag and less weight at the back (feathers and no metal tip). there is a reason airplanes are more stable when nose-heavy than tail heavy. i think you are confused because the thrust is coming out the back and you think that weight in the nose will make it try to point lower and wobble around. but remember, the thrust will only spin the rocket around if it has a loose nozzle that will try to keep going the same way while the rocket spins. i see why you were confused though. your idea would work great in a vacuum with gravity but no air (like the moon) so there would be no drag, but not in atmospheric conditions.
cbills2 years ago
nice water rocket
do you have a web site
oscarthompson (author)  cbills2 years ago
Unfortunatly not. You should check out aircommand water rockets though!


i like it!! definately gonna make sumthin like this one
teenuvibhav2 years ago
verry good ilike
leiamme2 years ago
What kind of plumbing coupling?
famos_amos3 years ago
what with the picture?
rocketman203 years ago
how long will the pressure hold
Wow, this is amazing! Keep up the good work!
Kryptonite3 years ago
Wow, nice build!
popscott33 years ago
What kind of glue should I use
oscarthompson (author)  needfortoast3 years ago
I used bostik soft plastics glue and it works fine for me. Although you can use PL premuim, but this is a bit more expensive and harder to get hold of in the UK, but it may give you better results.

who cares if he has a copyright?!?!? this is a great instructable that i used to spend a few hours with my daughter AND an instructional speech for my speech class. but the instructions you put on here were clear and easy to read. and i researched the launcher online for several hours and i believe this to be the best one.

i used the 2 bottle design and i used gorilla glue (which is stronger than hot glue). the thing reached 15 to 20 feet in the air and the reason for this failure was my choice of glue. the glue expanded like it is designed to BUT this glue is not a good adhesive for the plastic in the bottles.

i can see the potential if i just follow instructions (this was a problem for me growing up). i always think i can improve the process, but once again i am wrong. but my daughter had an awesome time, i had a great time, and we got the whole family together for the launch so the project was still an overall success. i will be building bigger and better in the near future.

thanks for the great instructable oscarthompson!
I used to make make water rockets when I was a kid.  All I ever used was a 2 liter bottle, duct tape, and the valve stem from a tire.  Drill a hole just slightly smaller than the valve stem in the plastic lid and jam the sucker through it as far as you can, wrap the bottle with duct tape (just one layer is fine) - this is a "better safe than sorry kinda thing" -  never had one blow up.  Fill the bottle about 1/5 of the way with water, use a hand pump or air compressor to add about 45 psi, turn upside down and unscrew the lid.  Mine usually went above 100 feet easy, of course I used a bit more pressure.  ;)
oscarthompson (author)  jason.buckmann3 years ago
Thanks, you made my day !
TSC4 years ago
I'm gus this does not go high   it looks to big to go high!!! But any way sweet!!! 5stars!!!!!!!!
Lowney4 years ago
Can we see a video of your big rocket?
max05064 years ago
what do you mean with rubber bung in the part list of step 10
oscarthompson (author)  max05064 years ago
rubber bungs like the ones in wine bottle's but rubber. Type it in to google images

I see thanx
i like the idea but i don't konw anything.
How can i do for fill the boosters?
do i have to put their a valvle each?
and are the boosters gonig to fall down?
if yeah how will i do it ?
thanks for the  ideas.

oscarthompson (author)  juanpedro1324 years ago
You can fill the boosters by putting the water in the top of the bottle. The bicycle valave will help prevent leakage.
The boosters will fall down when the thrust of the booster can no longer beat the air resistance thus gravity pulling the booster down.

This can be achieved by making three of the launch mechanism's just on one Pad ( two for boosters one for main)

rhendric4 years ago
good so far, but the diagram for this step cannot be viewed properly at the current size, and even when viewed at the right size, it is very hard to understand.
m_debator4 years ago
This is AWESOME!  Its the John Holmes of water bottle rockets.
gingerlad954 years ago
what is the materials list for this project

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