Backpack gun design

Build a homemade water gun or water balloon launcher and tell us about it.
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Nate
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Backpack gun design

Post by Nate » Wed Jun 07, 2006 6:49 pm

First idea I came up with. I based it off of one I already have, but it's leaking. Anyway, here it is: http://www.maj.com/gallery/Nate2/Rokenbok/design.bmp

There ya go. Criticize all you want, no matter what it is, it helps me out.

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Silence
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Post by Silence » Wed Jun 07, 2006 7:06 pm

Nice to see you used PVC Designer.

I presume you've read the HowStuffWorks Water Blasters article, but if you haven't done so yet, you should now. Generally, the flow of a soaker goes, "reservoir -> 1st check valve -> pump -> 2nd check valve -> pressure chamber (PC) -> trigger -> nozzle." I don't see how or where the pressure is created, because it appear to be missing one of the check valves and the pump. Do you put the pump in the backpack or use some other revolutionary design? If so, then elaboration would help on my part :confused: .

Nate
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Post by Nate » Wed Jun 07, 2006 7:20 pm

I knew someone would ask that. The smaller caps, between the tubes and the upper caps, go inside, filled with something sort of heavy. That's all like an exploded view. That pushes down on the water, keeping pressure. That's how the backpack one that I have works. At the 4 way crossing, the top has a cap (on a check valve) that would have a hose spout for filling. The bottom is just a handle.

Big Boss
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Post by Big Boss » Wed Jun 07, 2006 9:29 pm

Something heavy? Maybe springs would work. Although for any reliability, they'd have to be fairly large guage springs. And even then, I don't know what kind of pressure that'd create against liquids.

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Silence
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Post by Silence » Wed Jun 07, 2006 9:37 pm

I see what you're saying now, and I was going to ask about the smaller caps, but I don't think you realize exactly how much force is stored inside powerful homemade soakers. We're talking about so much force that you have to stop pumping a 1/2" pump--and if these are 3" tubes or something, there's no way you could get force. Also, once you managed to lift the weights and fill the reservoir/PC, you'd have to carry the entire thing everywhere. If you're thinking about the Power Pak, which does have three tubes as a backpack and a gun without a pressure chamber, then that uses a rubber CPS to constantly apply force.

EDIT: Welcome to Super Soaker Central, Big Boss.

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SSCBen
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Post by SSCBen » Wed Jun 07, 2006 9:50 pm

Yes, welcome to Super Soaker Central Nate and Big Boss!

Seems that you've got a handle on everything Nate. Since you are basing this off a water gun you have previously made, I am assuming that a weighted gravity-powered water gun was what you previously had made. How well did that work? I've seen old 1800s mining techniques use something similar, but I never thought it would work well enough in a small scale water gun! I might do the math right now to see how much force I could get from a water gun and if I'm not too rusty at my physics, I might be able to get some sort of stream velocity in the end.

The weight would also turn me off, which might be a good reason to use the springs Big Boss sugggested because they can offer more force, albeit less constant force. Air pressure would also provide non-constant force that would be even lighten than springs (and cheaper).

Nate
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Post by Nate » Wed Jun 07, 2006 10:42 pm

I haven't built one before. This is my first design, based off a CPS Super Soaker I already have. Also, the cap at the end of the gun will have a small hole in it for a nozzle. The top of the 4 way connection will have a cap with a faucet fitting on it for filling the gun. I haven't decided on how to tell if it's full or not, though.
Last edited by Nate on Wed Jun 07, 2006 10:48 pm, edited 1 time in total.

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Silence
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Post by Silence » Thu Jun 08, 2006 12:08 am

Sorry, but no Super Soaker implements such a gravity-fed design. In fact, the only backpack CPS soakers are the CPS 3000, the CPS 3200, the SC Big Trouble, the SC Power Pak, and the recent Aquapack Devastator. If you have the SC Power Pak (which is actually a decent weapon), then I wouldn't blame you for thinking that it uses gravity; it has three tubes, and they all have clear parts that show plungers moving up and down. However, they use cylindrical rubber PCs, which exert far more force than weights and with far less mass to carry around.

Of course, you might not even be talking about the SC Power Pak...in which case I'm totally clueless. However, I am certain your method has not been used before.

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DX
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Post by DX » Thu Jun 08, 2006 12:11 am

He has the Power Pak. And the idea actually might work, if the weights are heavy enough. We shall see...
Mess With the Best, Get Soaked Like the Rest!

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Lightbulb41
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Post by Lightbulb41 » Thu Jun 08, 2006 12:40 am

I think he would best go for a spring driven system due to the massive weights on that thing would take to put out alot of pressure. I used to have power pack which I modded to hook directly to a hose :) Big problem away from a hose though. It was a good gun until the seals went and sprayed everyone.
You can get more with a kind word and a gun than just a kind word.

I trade mobility for firepower. Accuracy for strengh. And Stealth for Intimidation.

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