Water Rocket Forum

Check this site:

http://www.wra2.org/forum/posting.php?m ... &f=3&t=457

Its a water_rocket car around a skate with a person on it.

Now that's what I call ingenuity . Looks like fun too

Andrewlee wrote:Now that's what I call ingenuity . Looks like fun too

I think there's a distance competition in the U.K. for water rocket cars. I saw it on TV a few months ago. They didn't go very far at all!

That's because they don't have any of us working on their side to help design and operate the vehicle. I'm sure with some more efficiently free spinning wheels, a lighter base, and some rework on the pressure vessel and nozzle, we could have them going a fair distance.

This french site shows how to make water-rocket car:

Model Mirage 1

http://pasylmat.perso.cegetel.net/voitu ... irage1.htm

Model Mirage 2

http://pasylmat.perso.cegetel.net/voitu ... irage2.htm


The videos:

http://pasylmat.perso.cegetel.net/video ... aster3.wmv

HI guys,

Its been a while since I posted but I did see this thread so I thought I would add some content as well. We have been working on a wrocket car over the last few weeks. It started off as a science experiment with my son (fellow wrocket builder and tester) and it has evolved from there.

We started off with a school demonstration so stability and predictability was the key before speed. When we built small light cars they were unpredictable, shooting off up in the air, left, right .. you name it. We ended up with a car that would go pretty much where we wanted, but rear end stability in high thrust siutaions was an issue.

We have worked on it to get it going pretty much straight now. Our highest launch pressures are 140psi with a 2.25L bottle. We have quite a few videos on our website of the launches as well and the development we went through.

We have just this weekend put together a 2 bottle wrocket car which we will be testing this weekend to make a 4.5L wrocket car. I will have some pics up soon on this car

We have found it very interesting to see how the wrocket differs when in a horizontal position, such as

- the ability to use much more water than when launching vertical
- the way the water and air mix under acceleration
- the lack of an air pulse
- the way a fin will work at lower speeds

Also its a good development platform for testing real wrockets without crashing them, just strap them to the wrocket body and go test. Especially deployment systems.

We have found we can go out, spin, roll and smash up the wrocket car and there is no real damage done. We have been able to come home from every launch in the last 4 weeks and not had to rebuild wrockets, we could just continue to develop the car.

A category on this forum for wrocket cars would be welcome .... there is definatley as much science and development work involved in getting a wrocket car performing as there is in working on a vertical water rocket I can assure you

-todd-
HHWRSA

I'd like to see more about water rocket cars on the forum too. I don't know many people doing this but if you think about it you don't need a huge field to launch a car from so more different people would be able to experiment with cars than with places or vertical water rockets.

Sounds like a good plan, Todd!

thampson wrote:
A category on this forum for wrocket cars would be welcome .... there is definatley as much science and development work involved in getting a wrocket car performing as there is in working on a vertical water rocket I can assure you

-todd-
HHWRSA

Here you go, a separate category for water rocket powered cars. I added boats too as the principles would be similar (although a boat would probably require a tiny nozzle). What might be interesting to see someone build would be a paddle boat powered by compressed air (anyone out there building one).

Welcome back Todd!

WRA2 wrote:

thampson wrote:
A category on this forum for wrocket cars would be welcome .... there is definatley as much science and development work involved in getting a wrocket car performing as there is in working on a vertical water rocket I can assure you

-todd-
HHWRSA

Here you go, a separate category for water rocket powered cars. I added boats too as the principles would be similar (although a boat would probably require a tiny nozzle). What might be interesting to see someone build would be a paddle boat powered by compressed air (anyone out there building one).

Welcome back Todd!

Since I live near the sea that has given me an interesting idea. Thanks for that !

Lisa,

thanks for creating the new category, that was fast.

I will be happy to add some more content on wrocket car development to encourage work in this area in the coming weeks.

Its always great to get new ideas with people work on solving the same problems different ways.

-todd-

We have been doing some digging into this subject and have found a couple of interesting sites.
Check out this Estes rocket car. http://myemrr.com/reviews/all/est_blurzz.shtml
It even comes with a digital speedometer for speed measurements.
http://www.estesrockets.com/assets/inst ... y_Cars.pdf

Here is the Tripoli rocket car rules.
Possibly a layout with classes like this could be figured out.
http://www.the-rocketman.com/rocketcar_rules.html

Cool stuff for sure.

-Tom

Tom,

thanks for the links you posted. I did read that the Tripoli rules mandate the use of a guide wire, so does the model you posted the link to as well.

We have found that a large percentage of the engineering effort with water rocket cars is controlling them. The use of wires seems to take a lot of this away. Having said that, its a great way to quickly get a water rocket car going and once the basics of the car are operational then the wire can be removed and the other aspects of car control can then be engineered.

We started with 1 bottle, 4 wheels and a piece of plywood and have worked up to the current 3 bottle car. You can learn a lot from testing a 1 bottle car, in fact what we learnt on the one bottle car allowed us to move up to the 2 and 3 bottle cars. Its also a lot of fun try to think through the problems, engineer a solution and get out there and give it a test.

We would love to see more water rocket cars on the forum so if you do build one we would love to see the results..

cya
-todd-
HHWRSA