Home made water rocket and launcher system

[c_dug]

People use mentos and coke on a bung release bottle, where building pressure as quickly as possible is beneficial.

Since my launcher is triggered and I can effectively set the pressure as I see fit, there'd be no benefit. Might have a go for the fun of it still!

Annoyingly I left the most important one way valve at work, 22 miles away, it's necessary for it to work with water. Might need to make a special trip to work just to pick it up!
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I am a bellend, I am a man of constant sorrow, I am a gummy bear, I am a rock.

[Pete.]

[oldpink]

the things you learn on BCF you never thought you'd need to know
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I have become comfortably numb

Theory & hazard 24-may 2016, CBT 8th June 2016, MOD 1 2nd Aug 2016 Mod 2 2nd-Nov 2016 - Current bike CBR 600 RR

[Polarbear]

[Tracer1234]

Good stuff. Any update on the testing/ final product
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Riding: Yamaha MT-09 Tracer Occasionally Riding: 08 Suzuki SV650, Potato: 2011 Yamaha YBR Custom.
Used to ride: 2015 Yamaha MT-09 Tracer (smidsy) 09 Triumph Street Triple (P/X'd) 08 Yamaha YBR (Sold)
CBT 04/14. A: Mod 1 & 2 13/04/15

[MCN]

2p worth.

You can limit any explosion by pressure testing using only water.
Since air can be compressed it is possible to get many more times the test vessel volume inside when under pressure. Rupture releases a massive amount of stored energy.
Water won't compress so you can bust the vessel with a little more than the vessel volume. Not as much bang for your buck. But a lot safer. Apart from the shower of water.
There is probably a rule/law/formula for how much water to use x air pressure x vessel dimensions x altitude x velocity.
But it's rocket surgery and I'm not going to give all the answers in this post. 🤣
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[c_dug]

It worked really well, my gauge maxed out at 100psi and we had it way off the end of the scale more than once.

Fins got ripped clean off the rockets.

Parachute worked fantastically given it was a release mechanism of my own design and making, though it did rip when we tried to attach a gopro to the side of the rocket.

I've got a few videos on friends phones, unfortunately mine went kaput a few days back so mine are all lost. I'll try and get my friends videos together when I have a phone back!
____________________
I am a bellend, I am a man of constant sorrow, I am a gummy bear, I am a rock.

[CaNsA]

[Pete.]

That equation is too simple for a water rocket. The mass of the rocket decreases rapidly as the water is fired out the back.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[UnknownStuntm...]

Fuxache. Just found this thread. Worked on something massively similar last week.

Project brief: Transport an egg along a washing line (40 feet) using a machine.

Immediately, I thought I'm gonna make a rocket. No Mechano, Lego or other motorised stuff, no moving parts, no bother.

V1: Zero research, cork trimmed to fit neck of 2L bottle. Hole for presta valve cut in cork, bottle half full, footpump to 30psi. Bottle in orbit somewhere. Did not even see which direction it went.

At this point I got a flat bit of wood, and put some hooks through it to hang it horizontally on a washing line, gaffa taped to bottle.

V2: Still zero research, smaller hole required. Cork with small enough hole for a needle adaptor. 20psi, wet feet.

V3: Complex presta valve mounted in modified bottle cap, with separate 'power' nozzle bodged from a large rawl plug and a wooden dowel deftly 'turned' using a drill. 4 inch 'safety nail' for um... safety. Cord through the end, pull cord to release wooden plug. 30psi: wet feet. 50psi: awesome controlled launch. 55psi: wet feet. 50psi: wet feet.

V4: Research performed, requirement for schraeder valve noted. Visit to local friendly tyre place and would you believe I met an expert. Quick bodge using a car valve stem with the valve removed, mounted in a bottle cap. Added washing up liquid. Footpump at 30psi meant I could 'gently release' the end and launch when I wanted. Perfect launch, moderate thrust and a lovely white bubbly stripe along the garden.

V5: Egg carrier compartment added to the front (another bottle cut off, egg carton inside), slightly moved the wooden hanger section forward for retained CoG. Bike track pump. 80psi. Bubbly white stripe. Bubbly white feet. Scrambled egg down fence of neighbours garden. Aching cheeks.

Most fun I've had making a mess in years.

Only have a pic of the V3 mechanism:
https://cdn.bcf.44bytes.net/files/img_20170817_204719.jpg

[Sload]

Think I would have kicked you lot around the workshop a few times by now if this is what you piss about with

Surprised the bottle withstands that pressure

[MCN]