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Posted: Wed Jun 24, 2009 12:50 am
by colty-bear
i want it to look some thing like this

Image

Posted: Wed Jun 24, 2009 4:27 am
by inonickname

Posted: Wed Jun 24, 2009 4:42 am
by Biopyro
http://forums.sscentral.org/44671-post38.html

Check out this one. It uses 3 components, fills from the mains (no pumping, no air tank) and can have a reservoir up to 8 litres (with a larger tank).

It's essentially a less complex version of this design.

Posted: Wed Jun 24, 2009 7:02 am
by btrettel
A few things:

The site inonickname and Biopyro link to would be a good place to start looking at what has been done. I would know because I run it.

A larger piston doesn't necessarily increase performance. There's no magic "surface area" increase in performance. The biggest effect would be more water capacity, which can increase performance a little bit, but not substantially. If you want higher performance (water output, at least), use a larger nozzle orifice or higher pressure. If you want higher range, add some glycerin to the water and mix it.

Fast opening valves are unnecessary and the complex flow paths introduce turbulence into the stream. The shots usually have a duration well above the opening time so ball valves (which have the simplest possible flow path as well) are adequate. As the stream is what is being shot, this is not desired because it will reduce range.

Getting over 70 feet of range with a water gun is fairly difficult. Some people have got over 80 feet but I haven't heard of anything over 90 feet that wasn't a pump meant for firefighting or a similar application.

Also, I'm still waiting for someone to outdo this water gun. This one operates at 600 psi and he used CNC machining to make it.

Posted: Wed Jun 24, 2009 7:08 am
by inonickname
So does it need to actually be a water gun; i.e. have a reservoir to store water or could a barrel simply be loaded with water? I smell a challenge..

Edit: why not, I'm gonna start planning a (less than lethal) water gun..

Posted: Wed Jun 24, 2009 9:56 am
by THUNDERLORD
btrettel wrote:....Also, I'm still waiting for someone to outdo this water gun. This one operates at 600 psi and he used CNC machining to make it.
That looks difficult to beat!
If he used some "mother's metal polish" after/or polishing compound and a buffer wheel it would look straight out of "Men in black 2"...
Wonder if he sells parts for it? I'd be interested in the spring and chamber. Looks like an automotive part(?).

@btrettel: I remembered "Super soaker central" after I replied, and your username, but when I clicked your username your personal site came up, so I didn't want to be mistaken.

One simple but interesting thought I've had on using high pressure, is that after the water is forced out, the air/gas pressure used to propel it is still available in the chamber to maybe perform another task(?)...For spudding maybe the pressure filling the chamber could cock a spring, be used and the spring released and no power loss (other than slowing fill time) for example...many uses for principal probably. 8)

Posted: Wed Jun 24, 2009 11:23 am
by spudtyrrant
MountainousDew wrote:The nozzle on the tank I have will shoot a steady stream for between 30-90 seconds, depending on how much water you fill it with. But in a water fight that will give you over a hundred shots (+/- 99 shots). And it has great distance, no actual measurements, but my guess would be 150 feet...
idk about 150 feet i've shot my 2500psi high output pressure washer for distance and it only went about that far maybe more like 80-90feet it sounds more reasonable :?

Posted: Wed Jun 24, 2009 3:43 pm
by colty-bear
i want to be able to put pressurized water in it than release it so ti shoots.

Posted: Wed Jun 24, 2009 6:42 pm
by inonickname
You won't be able to pressurize water, sorry. You will need to use air to store energy.

Posted: Wed Jun 24, 2009 6:45 pm
by colty-bear
I see. that sucks, i guess i will do the same design but the smaller pipe under the water tank i will pu a piston in. thanks

Posted: Wed Jun 24, 2009 6:49 pm
by Technician1002
Water under pressure is done all the time. Maybe you meant to say, you can't compress water. :D

Pumps provide water under pressure all the time. It's how a firetruck gets water out the nozzle.. :D

Compressed air under pressure is a great way besides a pump to deliver water under pressure. :toothy3: Thanks, I'll be here all week. Tada da boom

Posted: Wed Jun 24, 2009 6:55 pm
by THUNDERLORD
Technician1002 wrote:...Pumps provide water under pressure all the time. It's how a firetruck gets water out the nozzle.. :D
I PEEE like that.
the odd thing is it's rifled. IIRC it has 2 grooves and a bout a 2 in 24" turn.
It's actually rifled more but that's how.
So anyone who says rifling is no good for liquid probably doesn't have one.

Posted: Wed Jun 24, 2009 7:05 pm
by spudtyrrant
THUNDERLORD wrote: I PEEE like that.
the odd thing is it's rifled. IIRC it has 2 grooves and a bout a 2 in 24" turn.
It's actually rifled more but that's how.
So anyone who says rifling is no good for liquid probably doesn't have one.
you don't have anything on me i got the optimal 1 in 48" for my 50 cal ultra urine expeller o death muhuhahahah............jk...............o rly..............ya rly.....................r u sure.............stfu alter ego

Posted: Thu Jun 25, 2009 3:58 am
by Biopyro
Using a bladdered tank you can keep the pressure on the tank without having to pump it up repeatedly.

Posted: Thu Jun 25, 2009 11:59 am
by SEAKING9006
A squirt gun was something I planned on building this summer.

But it is far different from anything here. It's actually a copy of the prototype Super Soaker.


I saw a picture in either Scientific American or Air and Space of the NASA engineer's creation, the super soaker. It looked like something you'd find here.


Actually, I think it might have been Popular Mechanics.....