High Pressure Water Rocket Making Tutorial, Part 1: The Pressure Vessel 

Hi Jamie, thanks for the feedback, but we think there are plenty of interesting things that have not been done yet with regular unreinforced rockets that can be interesting and valuable. We're waiting for the ice to melt outside so we can test out our air-start staging system. There's plenty of stuff like that that has yet to be invented. Thanks again for the feedback!

Thanks, it's great to see someone else experimenting in this field. The more people who are involved, the more things advance.

Many thanks!

Thanks for providing the motivation!

Thanks, but keep in mind that teams have been doing this since around 2003. The first attempts were done by AGR, and they used a completely different method where they wound a single string of fibers around and around their bottles until it was covered. It's a much more difficult process. One or maybe 2 others had tried unsuccessfully to make rockets using woven fabrics around the same time. We were the first to successfully deploy the process in the fall of 2003. We've built a number of rockets like this to look at different techniques over the years since then. Our budget allows us to build one or two each season to see how much farther we can push the pressures, depending on the size of the rocket.

USWaterRockets There is a lot of techniques out there, but most keep this information close to their chest. It's good to see detailed videos like this coming out.

AscenderRockets Thanks for the words of encouragement. Hopefully the information will be of use to you or at least even if you never use it, it is interesting to watch for you.

This is another one of those projects that we start and work on and then put down and pick up later and put down and it drags on and on. We were supposed to have this published last summer on the 10 year anniversary of our first setting the Water Rocket World Record. But we started having way too much fun with our camera drone and our 3D printer. So it was just a coincidence this came out. Have fun with this! But be careful too!

Gorilla Cat Thanks for the feedback! We appreciate it. To answer your question, I am not 100% sure when the next part of this video is going to be released. The video and graphics are done and just waiting for the editing to be completed. That part is about half complete. Keep in mind that we're in the middle of our best launching weather at the moment and if we are out flying rockets or conducting experiments, or repairing flight damage, then we have less time for editing. There are some other nearly complete videos in the pipeline that we may look at first, depending on what is happening with the weather or how much time we have free. It's nice to know you liked this kind of advanced topic. We will give it more attention.

Good catch! Nobody else noticed that.

The launcher we use (The "Instant Launcher") will be documented in more detail in one of the future episodes. It's based on our "Split Collar Cable Tie" launcher (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-T0dKc0fkVko.html). If you look at the PVC nozzle in this video you can see that we made the nozzle so that it has the same basic shape as a bottle neck (with the threaded part cut off). That way it works on the same release mechanism abd o-ring launch tubes (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-X3Dd1HZd7fg.html) we've made for our bottle based rockets. Our LaunchPad Altimeter design will not fit in a T-12 or T-8 FTC rocket, It does fit in a T-17 FTC Tube, and the other rocket in this video that we made from 500ml Iced Tea bottles is roomy enough for the Stock LaunchPad Altimeter. However, it is quite easy to make the altimeter a whole lot smaller with some custom work. This guy made the whole thing about the size of a soda bottle cap! www.wra2.org/forum/viewtopic.php?p=17159&sid=d241e7b9251e1701ad55a8375f813ac2#p17159

It's cacbon fabric

Someone noticed! Awesome! We like to inject some humor into these technical videos.

We had problems with blowing out but then we figured out that we were just to aggressive saving weight by making the contact area as small as we thought. If you make the mating surfaces marge enough it will hold. You can also use extra epoxy to make a flange or lip on the end of the tube that keeps the bulkheads from backing out. It';s not really adhered to the bulkhead there, it's a physical barrier to keep if from moving out of the end of the tube.

Thanks! Yes, there are companies who specialize in making woven sleeves. It makes construction a lot easier especially on oddly bent shapes.

+USWaterRockets Roger all that....

There has been a lot of debate over the years about the DeLaval nozzle and whether there were any benefit to using one with a water rocket. We have never had an experiment with enough control to measure the usefulness of such a nozzle on water rockets for precisely the reason you mention. Since water does not expand, the only possible source for added thrust would be from the extra air that follows the water out of the rocket. Our "custom nozzle" design is purely intended to reduce aerodynamic drag on the base of the rocket. It's possible the long taper also helps reduce turbulence in the water as compared to the PVC nozzle, which you can see has only a slight cone on the inside (made with a the tip of giant drill bit).

That's a lot of questions! Let's get right to it. Carbon Fiber and Fiberglass are close enough in tensile strength to make little difference in your application. Where carbon fiber is better is in impact resistance. We discovered that this makes no difference to the typical person but in our case where we fly over a lake, the carbon fiber rocket will not shatter when it hits the water, but the fiberglass rocket will crack or shatter on impact with the lake. Neither of them seems to withstand hitting solid ground. So, we have used mainly carbon fiber for this reason. We already played around with info cards, and will add your suggestions when we get more time. The team has been doing 2 important builds in addition to this video and it has had everyone super busy. We had 2 days last week were it was around 40F (4.5C) and sunny, but the snow here is still about a foot deep and when it gets warm like that the snow becomes wet and really hard to walk in. So, we worked on our builds in anticipation of better weather in the coming weeks. But your question was about the weather in the "States", which is pretty broad. We could take a trip to Florida and have summer temperature and sun! LOL. But that's a lot of work! Thanks for the comments!

USWaterRockets Haha, I'm sorry about that weather question. It's quite unusual to me to ask for weather in a particular region because Germany is a pretty small country. Compared to you the weather in Germany is pretty nice, we had no snow since February and last week about 20C / 68F. Well, now it's colder again with 6-8C / 42-46F. Thanks to EU we are also able to travel to Italia or Spain without any pass controls or changing the currency so that's not big difference to you.One thing I noticed when playing around with the info cards is that you're still unable to ad links to amazon and the most other common sellers. Julian

RaketfuedRockets It snowed a bit more here today! It did warm up to about 7C in the afternoon when the sun was out, but it got cloudy and windy and then snowed. Mother Nature is not cooperating this spring. In past years we were out on the lake launching already.

+RaketfuedRockets So carbonfiber is the tool of choice? You alluded to metal is a no-no. So Ti cannot be used? Thanks for the video, and looking forward to the next.

I'm fairly sure you can get high pressure hand pumps

PLEASE TELL ME TOOOO

All carbon fiber is not equal in strength, weight, and thickness. Two or three layers of a particular low cost grade may hold less pressure than a single layer of top grade material. You have to pick a supplier and get samples and test them. The easiest way to do that is to make some short tubes of your intended diameter with various samples and pressure test them until they either fail or you prove which ones meet your pressure requirements. Then you can make a full length tube using the material you decided was best.

Sure thing, thanks for the response!