Hello. I've been an inactive member of Spudtech for probably a few years now and I've registered a new account. I used to go by Doom, but not any longer. Spudgun are great fun, but not quite my thing.
I've noticed a few here have built some water guns or discussed them. I've also noticed some links to my website, <a href="http://www.sscentral.org/">Super Soaker Central</a>. I'll admit, the website I have up is dated and a lot of the stuff on there is just plain lame compared to what I have now. A lot of the stuff posted here is misled or not too great as well. My hope is that posting here will generate some real interest in good homemade water cannons. No kidding on the cannon part either.
Today I finished my a big project of mine. Following my usual naming conventions, I titled it "Supercannon II" which essentially describes this water gun in one word: it is a super water cannon.
My goal with this water cannon was to get it to shoot over 70 feet. No one has done that before and I knew it could be done easily. In fact, today I got a distance of 73 - 75 feet without trouble and I'm set to try higher pressure and an optimized nozzle orifice diameter. To compare to regular water guns, Super Soaker brags that their guns shoot 35 feet. In reality that's a stretch and a plain lie. My range was measured however, and was twice as high.
I know my stuff when it comes to making a water gun perform well. That's why I choose a 1 1/2 inch internal diameter for this water gun, used 4 inch PVC for the pressure chamber, and bought a conical nozzle. The pressure chamber is powered by a piston - like a hydraulic ram. This separates the water and the air, solving the common problem of air floating over water. The piston also allows for linear flow to occur, which makes the streams nice and solid (and is very important for range). My digital camera is being used by someone else at the moment, so I don't have images of this water gun available currently, but I do have pictures of it and two videos:
<a href="http://www.sscentral.org/images/supercannon/video.mpg">Video 1 (562K)</a>
<a href="http://www.sscentral.org/images/supercannon/video2.mpg">Video 2 (564K)</a>
I'll get some images of the water cannon itself once I have access to the camera or memory card.
Here's a few still frames from the videos:
<img src="http://www.sscentral.org/images/supercannon/shooting.jpg" />
<img src="http://www.sscentral.org/images/supercannon/bigblast.jpg" />
Don't mind the cameraman too much either.
The second video is what people in the business refer to as a "riot-blast." To give you guys an idea of how powerful that is, take the example of the older Super Soaker water guns. Back in 1998 - 2002, the "X" system was used to approximate water output. The biggest water guns had output of 20X, which basically is 20 ounces per second (it becomes clear that the toy engineers weren't going to make a new unit). The video shot is approximately 375X of water output. The Super Soaker with the highest output ever made was 30X (the CPS 2000), and the one with the highest today was 10X (the Flash Flood). This is better than 35 Flash Floods and 12 CPS 2000s. A fire hose is 150X. You can imagine the recoil of this.
Another recent water gun of mine I know some here would be interested in is what I've titled "SuperCAP." The acronym in the name stands for constant air pressure, which basically means that I used regulated air pressure. This is one of the few water guns of its kind.
A few images in it's first incaration are available <a href="http://www.sscentral.org/images/supercap/">here</a>.
This was one of the few water guns I ran into safety trouble with. It's not that the pipe was going to explode or anything. In fact, I wish that was the problem. I was well within the safety zone. The problem was that the tubing clamps I bought don't hold up to the extreme force this water gun puts on the water. The tubing bursts off the barbed fittings I have and the water gun turns into a jetpack. I've had that happen when I was taking the backpack off and it smacked into my face, nearly fracturing my jaw. I'm looking into a few changes to the design obviously. Admittedly, my problem would have been resolved by simply reducing the pressure through firing the gun, but that'd make my garage wet and it wasn't on my mind!
This would be the water gun to take to a water fight though. It's not made for theoretical best performance, rather pure carnage. No one will outgun or outlast you. It also is a great pressure washer. With the right nozzles I'm sure it could be a water jet cutter as well.
Sadly I don't have any videos of this in action because I'm redesigning it. Recoil-wise this was my most powerful water gun however. Even though the output was only 120X, the velocity was very high and the duration was over two seconds. Due to the way you hold the gun you rotate when doing a high output blast like that. It's like shooting off a rocket. More recoil than a shotgun and it lasts.
Hopefully you guys will have some good summer fun with some kick-ass water guns you construct. If you've got any questions to ask about, I would definitely be one to ask. I've also seen a few of my cronies here, so they'll undoubtably be good people to ask as well.