Great Videos guys, Love to see this project finally closing in on the finish line. In your videos there are always one or two clips that make us laugh, for some weird reason. This time it was the plan of the adapter hanging on the wall. Even though there is more than a generation age difference and we life on the other side of this planet, it looks the same all along. 😂 Its just simpler to draw sometimes, even with the digital tools we have at hand today.
Thanks. I agree I am also old school like dad. Sometimes just drawing it out is the easiest. Actually now that I think about it, pretty much most of our technical drawings for this project are hand drawn. :)
Hola George, es admirable el método que aplican, antes de dar cada paso, van sobre lo seguro, excelente!! Estoy expectante por el resultado final. Saludos!
Awesome videos mate.....been watching you'all put this together for years and it's cool to finally see the project nearing completion. Do you'all have a tentative first launch time frame? I am assuming at some point this year yeah? Awesome job.
Thanks for following the project. This project has been going on for way too long, so we are in the final push to get it over the line. The current plan is to launch it in August during the club's high power launch. This is the only thing we are focused on at the moment, but still lots and lots to do.
Nice fix! Do you know if there is a limit to the number of pressurization cycles a particular booster can go through? Especially if you are hearing fibres snapping! Or is it likely plenty and not something to be worried about?
Thanks, that's a good question. There may be a limit to the number of pressure cycles, but we just don't know what that limit is. So far these boosters have had 2 cycles. My thinking on the popping fibers is that there would be a small number of fibers that are under much greater tension than most of the others. And so when stressed during pressurisation they are the first to pop. But eventually the remaining fibers that are more or less equally stressed take up the load much more uniformly.
@@AirCommandRockets I agree. Does the crackling/snapping significantly reduce or disappear on subsequent pressurizations? Although that alone may not be an accurate determination of integrity
This is exponentially next-level home-engineering of the plastic pump-&-water rockets we played with as kids. We always puzzled over how much air space to leave for how much water to add to the chamber. How do you determine this? Can just smh in admiration...
The general rule of thumb is 1/3 full of water, and 2/3 full of air. For a more detailed analysis here is a full article: www.aircommandrockets.com/water.htm
Thx for sharing. It might be a better call to add much more material on the outside of the booster around the root of its neck. The sharp changes in the contour of the booster in that location will always be an area of focused and alternating stress loads, promoting any kind of delamination leakages. To stiff it up, preferably with the material with the same elastic properties, to avoid delamination, in my opinion, you need to add more layers of fiberglass and resin - blending the transition from bottom of the tank to the nozzle much more. If a total blending isn't desirable, then at least make the cave radius on the nozzles neck root the same as the domes' radius for the bottom of the boosters main body.
All good points. The diagrams showed a very simplified representation of the structure. The layers are curved at the transitions, the glass layer on the inside is also much thicker, and what wasn't shown in the diagrams are the extra sections of fiberglass tow around the transitions. Here are the details of the actual construction. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-plU5c-Embtk.html and here is a cross section of the joint: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-jnUZ-I5gyOg.htmlsi=O4KeQ_93XnKD32v6&t=218 and also here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-hFptNGZcD64.htmlsi=aXHyCDiq153srJvV&t=561
@@AirCommandRockets I replied to you yesterday, but it was too long and unspecific. Sorry for that. In your Part 29 clip, there is a good schematic picture, time stamp 4:15. I would have made the gray layer different (you are referring to it as a 3" layer of biaxial carbon fiber sleeve). To distribute the loads and disperse their focus more evenly, I would have blended it on the outside from the top to the bottom in a way that the outside shape would have appeared conical while keeping the inside design as it is now. The height of the blending transition from the bottom of the nozzle would have been at least 7 mashes of the brightest lines, almost the whole height of the presented part.
hmm, not quite sure why you needed the extended nozzle? wouldn't a sleeve alone have been enough? like a 1mm thick steel or stainless tube with a snug fit going over the existing nozzle to prevent it from expanding?
The problem is that it was now delaminated so there was a path for air to flow on the outside of the aluminium nozzle. At 1000psi air will find a way of getting out.
7 месяцев назад
69BAR 👏👏👍👍👍 What is the length of the boosters ? :)
Kind of ... although the exhaust by-product is water, it is also accelerated as a result of a chemical reaction. A traditional water rocket does not use any chemical reactions or phase changes in the propellant to produce thrust. -> Just cold gas accelerating a cold liquid.
Oh that's easy ... I stick my fingers in my ears and go LALALALALALA. But seriously it is a concern. So far we haven't seen any adverse effects on the pressure chambers but that doesn't mean it won't be a problem later.
That's exactly right, the same weight penalty on the sustainer would be much worse. The booster's take off weight including water is close to 15Kg, and the extra weight is only 0.2Kg so about 1%.
