Jump to content
Light-O-Rama Forums

Water Cannon FYI


tjflory

Recommended Posts

Here's what I learned in my air powered water cannon tests.

Keep (air) pressure reservoir pressure down about 70 or 80 lbs.
The 1" orbit sprinkler valves I use are rated for 115, but 2 failed at this pressure.
No problems since turning pressure down.

My 2 ended water cannon is: 3 ft long 2" reservoir tube. 1 1" orbit valve on each end. on each end water is fed into a T from another (3/4) orbit valve. then about 1.5 feet of 1" pipe, an elbow pointing up, a short piece of pipe/reducers etc to get desired effect.
(mist, spray or jet)

Enjoy

tj

Link to comment
Share on other sites

Sorry.

I don't own a video camera and phone video is useless. I would send some pics but I've put it away til July 4 show. (its actual purpose) I'd be glad to answer any questions though.

Sorry again.

tj

Link to comment
Share on other sites

Take that back. I decided to put a pressure regulator right on it. Here's a pic.
(wow, my new phone takes nice pics!)

The fitting in the middle is horizontal during operation and it is attached to the back of my fountain.

tj


Attached files 315932=17248-IMG037.jpg

Link to comment
Share on other sites

  • 2 weeks later...

I'm not an expert in this use or anything like it but I'm surprised you are using sprinkler valves for this. For your use, do they actually last over the long term? For a long time now I've been wanting to do the jumping fountains such as is at DisneyWorld and I know how to do it other than finding decent valves that will open and close fast enough and of course two different pressure pumps and etc... to make it work. I would love to know more about how you are doing your display and certainly would like to see the video when it comes time for you to put it out. When I hear the words like water cannon, my first thought goes to the Bellagio Hotel/Casino in Las Vegas and how cool would that be to do it!

Link to comment
Share on other sites

I actually have 3 fountains and 1 (2) barrel cannon. Cannon may not be the best word... maybe blaster? Depending on pressure, tube size and amount of water, I can make a broad misty blast about 20 feet high or a blast stream 50 foot plus. both the fountains and the cannon use 1" sprinkler valves. (12 bucks each). As in my previous posts, durability was an issue with the cannon, but I think I've solved that problem with lower air pressure. I have had no failures on the valves in my fountains.

Now for speed... the fountain valves open quickly, but can close very slowly.
(because of their type) If there is another valve open, it will close faster. If it is the only one open, it can take 2 to3 seconds to close. I adjust for this in my sequence. I did this water thing kinda for fun... low budget. If it goes over well I will be changing to a different type of valve... about 16 bucks each. Should be nearly instantaneous response.

tj

Link to comment
Share on other sites

May I ask what you are using for a pressure vessel? Storing and suddenly releasing a large volume of water under pressure, I would think you'd need fast acting valves of the industrial variety. Before I retired, we used solenoid valves for opening and closing liquid nitrogen lines, but some were specifically fast and others slow on purpose. I've never designed anything for water but guessing someone would simply fill the line/tube first, then open the high pressure air to the bottom of it and dump a ton of pressure which would force the water out such as firing a bullet...if my thoughts are correct?

Link to comment
Share on other sites

Take a look at the picture in this thread. The pressure vessel is 2" schedule 40 pipe about 3 feet long. Its hooked by a hose to my compressor.

Link to comment
Share on other sites

The brass fitting in the middle is horizontal @ operation. the tubes on each end are filled with water by a valve (a channel in the sequence). the ends are T's with 1 side plugged basically to make an elbow and a foot to contact the ground to take the recoil (which is considerable). When the valves open (another channel) the water can only get out 1 way... up.

tj

Link to comment
Share on other sites

Oh yeah. The duct tape is holding on a foam cushion to prevent the recoil from shattering the T. The duct tape on the other side of the T is to keep critters and/or bugs out while it is in storage.

Link to comment
Share on other sites

Also, remember air is compressible, water is not. In this case, its not so much a function of air pressure as it is air volume. You are displacing water with volume... not pressure. The Bellagio cannons use a little over 100 psi, but a semi trailer tank worth of volume. They are also submerged so they work a little different than mine. They have a vertical tube with a split butterfly check valve at the bottom that simply allows the water in after the tube is emptied. There is a large air line that comes in the bottom just above the check valve. The cannon is fired by blowing a large volume of air into the bottom thus forcing the water out the top. The check valve at the bottom flops closed so the water cant go that way. When the tube is empty, the water seeks level and the pressure of the water wanting in opens the valve and it all starts over. I did mine the way I did because I wanted it to be compact physically and visually. Its only 6 feet long and tucks in behind my fountain nicely.
tj

Link to comment
Share on other sites

That's how I was thinking they possibly did their cannons which made sense. Now getting that much air-pressure to dump suddenly and of course storing that air-pressure is the feat to accomplish. But, for a yard display its really not needed. While watching the video of yours, I was thinking how cool it would be to add a laser to the inside of the water stream as well. You probably can't put a laser itself directly into the stream but you can isolate it using fiber optics. The thought was, having the stream illuminate while it fires.

Link to comment
Share on other sites

I'm not sure what video you are referring to but I haven't made one...yet.
Anyway about the lighting. I hadn't thought of a laser... I'm not sure what that would do. My fountain lighting is not in the water streams but just below. It actually looks pretty good on a dark night. I have strobes behind the mist cannons and they work well also.

tj

Link to comment
Share on other sites

Oops, Sorry about that. I saw someone's video of a water cannon and just assumed it was yours. Watching whomever's video, I noted that they had a flood lamp on it but it really didn't show it off that well so the thought of a laser within the stream as it fired upward might or might not work but keeping the laser out of the stream by using fiber optics would be the answer there. It wouldn't cost too much to find out but then again, if it didn't work, then its money lost.

Link to comment
Share on other sites

The laser idea is intriguing. Id like to see it done as a test.
A few concerns if I may:

1. Laser light travels in a straight line and cannot be seen from the side unless it hits something.

2. I think it would take a powerful laser... more powerful than a pen laser.

3. Light will travel through a laminar stream like a fiber-optic tube, but if there is a break in the stream, there is a break in the light.

That being said, It could all be wrong. Looks like somebody's gonna have to try it!

tj

Link to comment
Share on other sites

Oh yeah, don't try it with a cannon like mine... you'll never get the steam laminar. use a nozzle like the old fashioned hose end kind.

tj

Link to comment
Share on other sites

  • 3 weeks later...

New pic of my fountains/cannon which BTW worked great in testing yesterday. (not braggin.. just kinda surprised...)

tj


Attached files 319796=17449-IMG049.jpg

Link to comment
Share on other sites

tjflory wrote:

New pic of my fountains/cannon which BTW worked great in testing yesterday. (not braggin.. just kinda surprised...)

tj


I am so jealous! Do you have a video of the testing?
Link to comment
Share on other sites

Sorry. it was really windy and not much to watch in the daytime. I promise i will post a video of my night tests later this week.

tj

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...