Should have Posted this Here- Need Help on a Fun Project

[mcnewt]

Ok- I am going to admit I know ZERO about water guns. I know a lot about hydraulics as I am a mechanical contractor. Here is the deal and why I ended up here. We have a customer that sponsors a mud run for kids to benefit a local children's hospital. We do a lot of work for both the hospital and this customer. They approached us to build a "kid wash"- basically a tunnel between two roll-off containers that the kids run through to wash the mud off of them. I wish our engineers and designers would spend as much time on their real job as they have on this one. It has been fun and I will post some pictures when we are finished with this. But I found this site because I have a vision that as the kids run out through the tunnel the parents or others pay a few dollars more and man some turret mounted water gun (or two) at the end of the tunnel- dousing the kids as they run through. I was hoping someone could help me design a turret gun- looks cool, not time consuming to build, safe (the kids might be as young as 5), and Friggin' awesome. Anybody have any advice? Oh yeah, we are connecting to a fire hydrant (city donated the water and it flows to a retention pond where it will be pumped and used for irrigation later)- The wash will take about 500 GPM so we still have about 1000 GPM available for the guns (I assume that is more than enough for you hard core guys) at about 50 psi (the hydrant is about 300 feet away so I am assuming pretty significant pressure drop) The tunnel length is 25 feet. We have access to pretty much any type/shape/size of pipe, valves, and fittings- We also have a full machine and welding shop so go crazy, but I if I didn't mention it, this is a donation, so don't go too crazy with our money.

Information on the event can be found here- http://www.dirtyscurry.org

Thank you in advance for your help.

Tim

[HBWW]

How fancy does it need to be? Does it need to be stationary? Have a trigger?

[the oncoming storm]

you are way overprepared for this

make 3/4 " PVC frame tall enough for kids to walk through and make sure that each frame has a 3/4" PVC threaded fitting for connecting to a garden hose and drill 1/8" holes facing inward to spray make a series for these to get to 25'. One hose connection should support 2 4x4x4' frames with adequate power
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don't over engineer it

[Nemesis]

Oncoming Storm, I believe he has the wash part done, I think he desires a stationary, turret esque cannon to hit the kids again.




Hmmm I would think a large, motorized pump, perhaps similar to the one used on the MOARC would be useful. Info on that is somewhere on ssc. Whatever happens, give us pics when its done!!

[the oncoming storm]

well then just use a fire hose

[Nemesis]

Yes, if there is enough pressure.

[martianshark]

So are you saying that the gun will be connected to the fire hydrant? If so, it seems all you want is a really fancy hose nozzle. The challenging part may be building a trigger system and a rotating turret part, which I don't think most of us really know much about. But it shouldn't be too hard to design if you or someone at the metal shop knows what they're doing.

In its most basic form, all you really need is a valve with a hose connection on one end, and a nozzle on the other end. On top of that, you will probably want to add a comfortable handle, and a trigger mechanism of some sort to open the valve. And then you'll want a turret to mount it on.

Anyway, the way you design it is pretty much up to you. I couldn't build it any better than you probably can.

[soakinader]

I think building the turret is the most important. I would use a cinderblock and a road cone as the base (or WHY). Put a piece of 4-5 foot PVC pipe in the middle with an internal plug. Put a T connector on top. Attach intake (water hose to one end and a big ol' valve to the other end. Use 3/4" or 1" PVC and use whatever adapters, teflon tape, PVC cement and threaded parts as necessary.
I have been looking for a fire hose nozzle (similar to an XXP 275/SS 300) that looks something like this:http://www.apollointl.com/MARINE_SAFETY ... NOZZLE.jpg
Or, you could just use a ball valve with a nice big handle. Attach a PVC endcap to the business end and drill several small holes to get the desired effect.

[marauder]

well then just use a fire hose

They use those to control riots, not to hose down kids