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Water Balloon Laucher
Last Post 14 Jul 2013 02:18 AM by tommir right. 8 Replies.
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SZXDuncan
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Posts:4

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08 Feb 2012 10:23 PM
    We have a project that we want to build a water balloon cannon. It's something like a confetti cannon but instead of using confetti as ammunition, we use water balloons.

    Well, we want our outcome is to have a water balloon cannon that is efficient in loading and unloading balloons, launching the balloons out of the launcher without even breaking the water balloon. And we want to scale it up to maybe a RPG sized cannon.

    As in Plan A for propulsion, we had pressurized gas tanks to propel the balloons, but we are afraid of how impractical it is in releasing the proper amount of air to propel the balloon far enough.

    Plan B would be using spring, cock it and release it.

    Please advice. Thanks.
    zoranbd
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    Posts:4

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    09 Feb 2012 08:42 AM
    How do you intend to keep the balloon from bursting? It might be difficult to keep the balloon intact travelling through the barrel. The balloon should probably sit in some sort of a pocket in the barrel(kind of like where you put a rock in a catapult) that will keep it protected from the rubbing on the sides of barrel. If you do this you can probably use just about any mechanism from a spring loaded system to a pneumatic system.
    Niel
    Basic Member
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    Posts:193

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    09 Feb 2012 01:01 PM
    You could use a Sabot [ http://en.wikipedia.org/wiki/Sabot ] to protect the balloon from the barrel. Design the sabot so that it just barely gets out of the barrel before it separates from the balloon.

    Compressed air should work very nicely in this type of application.

    Alternate you could design the gun to be more like a sling shot (there are lots of these) or a catapult [ http://en.wikipedia.org/wiki/Catapult ].

    Niel Leon
    engineering.com
    SZXDuncan
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    09 Feb 2012 10:39 PM
    Then how about the pressure inputs? Cause we were thinking about paintball canisters. But we are afraid there wouldn't be enough power to push the balloons.
    Niel
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    Posts:193

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    11 Feb 2012 02:32 PM
    Paintball guns use either CO2 or Nitrogen as the propellant. The pressure is typically reduced to a lower pressure in the gun.

    Is with all gas propellants the force available is a function of the gas pressure times the working area. The power is a function of the gas pressure and the working volume.

    The you would need to do some engineering calculation to determine exactly how this system would function. Performing the detailed calculations would constitute Engineering advice. Here is some guidance.

    1. The material in most paint balls is essentially water with some pigment. As a result the density of paint balls will be approximately the same as a water balloon.

    2. The energy of a projectile is 1/2 mass * velocity ^2. So if you know the maximum speed you want for the water balloon you can calculated the amount of energy you need from the gas.

    3. The amount of energy or work from a compress gas is given by W = integral(P dV)

    By sizing the components correctly you should be able to make an air power water balloon cannon. It would be no different than a squirt gun except you need to protect the balloon surfare from damage.

    Niel Leon
    Engineering.com
    SZXDuncan
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    Posts:4

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    12 Feb 2012 05:06 PM
    Alright thanks alot! There's a start then.
    Greg
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    Posts:3

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    16 Feb 2012 12:17 PM
    I like the Sabot approach. Multiple or flow adjustable valving may help with gentler acceleration to final velocity. Less stress, however that doesn't deal with friction and tearing. I think the large naval guns have a taper allowing for a more gradual acceleration because of blowby near the breech. Guess now I have caused a constraint requiring consistent balloon diameter...
    SZXDuncan
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    Posts:4

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    17 Feb 2012 01:59 AM
    I've taken out the gas canisters and instead, i'm going for a more reliable approach. By have a reservoir of pressurized gas of 70 psi, and using a sprinkler valve to release the gas.
    tommir right
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    Posts:1

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    14 Jul 2013 02:18 AM
    I would very much like to pay someone to assist me with a dyi air canon project



    My name is Tommie Right and my inner city youth league and I are  attempting to develope a science program that would involve using a  customized air canon  (which is safer and quieter than a traditional  customized potato gun) to teach basic principles of physics to at risk minority urban youths.

    A shoulder Fired Water Balloon Launcher and your Water Balloon Mortar like those found at www.myaircannons.com, or the air cannon that you have featured on your cite seem to be the perfect fit for our new program.

    And by having to operate in a city enviornment sound suppression would be an absolute prerequisite. Further more I thought having the chance to teach inner city youths the value of experimentation (i.e. launching prepackaged containers and measuring distances traveled, trajectories followed, and speeds attained) would be an excellent in road into the wonderful world of science.

    would like to buy some of them from you if you or someone skilled in diy building can construct some of them for me.

    i have specific requirements that need to be met.

    I need the barrell to be at least 3 inches in diameter.
    i need the barrel to be no longer the 3 three feet

    It needs to also have the ability to fire quitely ; (or at the very least not sound like an explosion when it fires)

    lastly it needs to have an effective range of at least 100 to  250 yards

    If you can fill these custom orders I will buy several of them from you so as to compensate you for your time and effort.

    So I'm offering you an opportunity to both make some legitimate money and assist me to try to get minority inner city youth interested in science.

    Basically I'm ask for your assistance, not so I have water balloon fights, per se, but so that I could try and get young blacks and hispanics to develope an interest in science so that they can see they have so much more potential then they realize and they can be anything that they want to be in life.

    I really hope that you can help me as I look forward to purchasing some of these units from you or someone you can recommend immediately.

    It is summertime after all:-)
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