Project week

Discussions about rockets, construction materials, adhesives, nozzles, nosecones and fin design.
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bugwubber
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Re: Project week

Post by bugwubber »

That looks awesome. I'd observe a strict 50ft safety perimeter for the metal though. Consider wrapping the metal in duct tape so at least no edges.

Good luck!
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anoymous
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Re: Project week

Post by anoymous »

thanks for the safety hint. I don't think the bottles will explode, though. we launch at 5 bar (72.5 psi). only a very weakened bottle would explode and when it is weakened that much, I don't think it will fit on the launcher.
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bugwubber
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Re: Project week

Post by bugwubber »

After several hundred rockets, we finally had one randomly explode in the 75psi range- likely due to a defect in the bottle. If you pressure test the bottles before adding fins, that should increase your safety factor.
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Blenderite
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Re: Project week

Post by Blenderite »

Be very careful with the metal on the fins there.
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anoymous
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Re: Project week

Post by anoymous »

All our tests are done right now. Now I will probably take a long pause from developping. Maybe I will try some things this summer, but at the moment, I won't launch.
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
- Albert Einstein

Sorry for malconstructions in my sentences, I am Belgian. And I was never good at making easy sentences.
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anoymous
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Re: Project week

Post by anoymous »

The higest altitude recorded was 40 m (131 ft)
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
- Albert Einstein

Sorry for malconstructions in my sentences, I am Belgian. And I was never good at making easy sentences.
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U.S. Water Rockets
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Re: Project week

Post by U.S. Water Rockets »

Blenderite wrote:Be very careful with the metal on the fins there.
We did some tests a few years back. We glued coins onto a bottle and exploded it next to a ceiling tile and the coins would pass right through the tiles if they hit edge on, and the coins would leave a 1cm impression in the tile if they struck it face first. This is just using a regular 2 liter bottle. We're not kidding around when we caution against using metal parts.
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Re: Project week

Post by U.S. Water Rockets »

That looks good. The sheet you used to cover the parachute looks solid. We might try something like that. Maybe we can even get it in different colors to accent the rocket.
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anoymous
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Re: Project week

Post by anoymous »

The cover is made from a plastic ring binder. It is pretty strong, exept when you get a lawn dart. then it is torn. That cover is the second of three.
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
- Albert Einstein

Sorry for malconstructions in my sentences, I am Belgian. And I was never good at making easy sentences.