Supercannon II complete

[Ben]

Supercannon II is my latest homemade water gun. Supercannon II achieved a range of about 73 feet, which is very good.

More pictures to come soon.

Video 1 (562K)

Video 2 (564K)

[Silence]

Very impressive. It sets a new record for range (now we can brag that homemades reach 60-70 feet "easily"), and by the looks of it, for output as well. The second video shows the pressure chamber emptying nearly instantly, and the recoil looks quite large. I just love how it blankets a huge area with water instantly, even if there's quite a bit of turbulence.

This might sound a bit off topic, but what were the results from water cannons? I seem to have missed out on that, although I hear the output is ~110X and the range is good.

Exactly what pressure did you pump this weapon to in order to get this range? How long did it take using a bicycle pump to obtain that pressure? I understand this weapon probably won't be too effective in battle, but it might be nice to know this information anyway.

So, as I said in the 70-foot Challenge thread, congratulations on achieving this performance . It sure looks like bike pump-powered soakers will be leading the way in the near future.

[radman]

Nice, I have a question though is the pc horizontal or vertical? Other than that nice range and great spread of water

[Drenchenator]

Exactly what pressure did you pump this weapon to in order to get this range? How long did it take using a bicycle pump to obtain that pressure? I understand this weapon probably won't be too effective in battle, but it might be nice to know this information anyway.

This gun was not pressured with a bike pump. It could be pressuring with a bike pump if you got the right fitting (its "input" is just a female adapter and check valve), but we (Ben and I) pressurized it with our air compressor. I operated the compressor while Ben checked pressure in the gun (it has a pressure gauge). The 73 foot shot was at 100 PSI. I am pretty sure that all of the shots that Ben did had about 3L in the chamber.

The riot blast was at about 70 PSI. Judging by the video, Ben said that it emptied in 4/15 of a second. A little math tells you that that is 375X average output (3000 mL in 4/15 of a second, 100 ounces in 4/15 of a second, and so on).

I don't think that this thing is the pinnacle of "battle practicality". But I do believe that good statistics can translate in good use in a battle, so you never know unless you use it in one.

Nice, I have a question though is the pc horizontal or vertical?

The PC is horizontal, thanks to the use of the piston. Normal air pressure can't be shot this way, but the trick is to use a piston to separate the air and water. This allows you to optimize the flow and make it be shot horizontally.

A lot of other questions can be answered by Ben in the iSoaker discussion on the same subject. I merely helped him pressurize it and took the videos. Sadly, Ben does not have a lot of pictures now (at least on the computer), but I can tell you that it looks similar to the original Super Cannon, except that a filling mechanism is at the end.

[Ben]

Some interesting specifications:

Pressure chamber diameter: 4 inches
Internal diameter: 1 1/2 inches
Pounds of force: 1250 pounds at 100 PSI
Nozzle orifice diameter: 1/2 inch
Nozzle type: conical nozzle intended for use on a fire hose
Water capacity: 3 - 5 liters

The 4 inch pressure chamber diameter is important. To get a similar amount of force with a 3 inch chamber, you would need to use 180 PSI. However, to get a similar amount of force with the next common size, 6 inch pipe, you would only need 45 PSI. Of course, 6 inch pipe is several times more expensive and the pistons needed would be as well.

1250 pounds of force should be the amount needed to get 70 feet in an efficient design. Remember that pressure = force / area, so force = pressure * area. Knowing the 1250 pounds of force is what is needed to get 70 feet in an efficient design, you can calculate what pressures you will need to get based upon the diameter of the chamber.

And yes, that is correct physics. I checked multiple books at the library and every single one says the force of pressure is the pressure times the area. Even still, the units for pressure are pounds/square inches, so logically multiplying by a unit of square inches would reduce to simply pounds.

The fire hose nozzle was McMaster-Carr part number 6424T62 for those looking to duplicate this design. That'll cost you $6.43, but that's well worth the price. Other fire hose nozzles cost significantly more. This is actually why I chose the 1 1/2 inch internal diameter. The conical shape definitely produced a cleaner stream.

Also, I'm considering threading on a 1/4 inch schrader valve to where the air coupler currently is to see how quickly I can pressurize with a bike pump. That'll be done later however.

[DX]

This might sound a bit off topic, but what were the results from water cannons? I seem to have missed out on that, although I hear the output is ~110X and the range is good.

SuperCannon II is a water cannon, of the superior piston air pressure variety. Plain air pressure needs things like an area for the air in order to perform like that. Plain air pressure also doesn't use all of the water. Obviously you can tell that my next water cannon, the Death Cannon, will use a similar piston setup if I can get the piston. A firehose nozzle for $6 actually sounds pretty good, so that's on the list as well.

[Prof_Slammin]

It looks like it has a lot of power, but I can run the videos for some reason .

[Ben]

You can run the videos?

If you are having trouble running the videos in your browser, right click and do save as. View them in a movie player. I encoded the videos in MPEG1 for compatability.

[Prof_Slammin]

Originally Posted by Ben

You can run the videos?

Yeah I was just about to change that, I mean "I can't the videos." But I'll try your suggestions (can't wait to make a homemade).
Edit:That was very nice, it's like the Flash Flood's riot blast with much more power and distance, but with the same amount of recoil (quite impressive). You should add this to the main site. Seeing the gun in video action inspired me to make a homemade. Sad part is, I also want a cheap video camera Walmart that will probably sap me of all my money.

EDIT by SilentGuy: I fixed your QUOTE tags, as the closing one wasn't complete.

[Silence]

@ Prof_Slammin: You got it--seeing that type of power should help motivate others to build homemades. The Flash Flood's special nozzle has measly output, and with much less lamination and shot time, compared to CPS soakers--and the Supercannon II far outclasses any commercial soaker.

@ Ben: How much is left for the SSC update? Things like this really do need to get there.

[Ben]

Originally Posted by Prof_Slammin

That was very nice, it's like the Flash Flood's riot blast with much more power and distance, but with the same amount of recoil (quite impressive). You should add this to the main site. Seeing the gun in video action inspired me to make a homemade. Sad part is, I also want a cheap video camera Walmart that will probably sap me of all my money.

I'd say any comparison to the Flash Flood would be wrong. Way more recoil than any Flash Flood. It would take 38 Flash Floods to match the output of this one water gun on it's riot blast, and 13 to match it's nozzle. You have to realize that I'm very used to water guns that are far more powerful than most.

I actually don't even own a digital camera. This video and the images I have taken were on some one else's camera. So go for the water gun and borrow whatever else you need. You can't borrow anything like this.

@ Ben: How much is left for the SSC update? Things like this really do need to get there.

Loads. Lately I've been doing other work to catch up and not all my attention has been here. I think the full update can be completed before next year. The current website and system aren't done at all as I'd like, and I realize the importance of getting new content up, but I'd much rather get it up on a better structure and system.

[Ben]

Just did some more testing. These two are separate shots. No glycerin was in the chamber when the output test was done. A video of the output test shot will be available. Videos would be great for measuring output of most water guns to get the exact duration, but when you're counting frames it gets real difficult.

These kids from across the street came over and talked to me for a minute too... they seem really interested.

95 PSI shot with 5% glycerin: 78 feet
Output at 100 PSI: 542 - 812X

The fact that the glycerin didn't add too many feet to the range was due to several reasons. There was a light wind from the side and against me. That however did not affect the distance too substantially. The real reason is probably because this water gun is extremely efficient to begin with, and while glycerin will help prevent the stream from breaking up, the water gun was so efficient that the stream did not break up much to begin with.

The output shot was incredibly powerful. If I didn't wear the strap I am sure I would have dropped it. This felt like a rocket was going off with me attached to it. That's probably because a water gun pretty much is a rocket.

I also measured the chamber size at the piston distance I had set earlier. The chamber hold approximately 3250 mL. That increases the 100 PSI output with the fire hose nozzle to 135X and my previous non-nozzled output to 406X.

Edit: Due to the low precision of the camera frames, I'm giving a range for the output. There's no way I really can determine exactly how long the shot lasted with only 15ths of a second precision. So I'm giving the shot time as 2/15 - 3/15 of second.

[CROC]

Will you be posting instructions on how to build Supercannon II? If so, when will they be put on the site?

[Ben]

Sure, there will be a guide eventually. A guide that will be as detailed as possible will be written. Given the work load needed to redo much of the website, that'd be on the backburner for a while however.

The thing is, if you can't build it from the pictures and descriptions I've provided, I highly doubt you'll be able to build it at all. It's really simple and straightforward. All the people who will build it need really is a description of how to build the piston and get it in there. That's the only part that's not obvious, but I don't doubt that anyone with the pistons could figure it out themselves.

That and it's Supercannon II, not Subercannon II.

[CROC]

I know most of it, I just don't get how you made your piston. It looks like it is made out of fiberglass or something.