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Posted: Thu Dec 02, 2010 9:02 pm
by ilovefire
saefroch wrote:2-3m is a long ways to be propelling ANY liquid, be it water or some other liquid, in a coherent stream. You'd probably want to research nozzle designs before buying anything, but I will say this, though I know very little on the topic: I'm fairly sure that attempting to make anything that looks like a DeLaval nozzle won't make a coherent stream. You'd need some length of tubing with an ID close to the intended stream diameter.
i have already got a length of small tube that i connected to a 3ml syringe and managed to make about a 2m "water" spray, so the nozzle isnt the issue here it is a safe valve that i could use, maybe ill try a spring loaded ball valve, just need some money first
Posted: Thu Dec 02, 2010 9:15 pm
by saefroch
If you use McMaster to order parts or at least look them up somewhere else, you can check how durable the seal is on the valve. Only trouble is it may be cheaper to just replace a cheap valve than buy a good one that won't wear out for a long time

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Posted: Thu Dec 02, 2010 9:42 pm
by Zeus
The syringe type water gun is similar to a springer type watergun, your hand being the spring.
I wonder if using too high a pressure in a watergun would just blow a hole in the middle of the stream like overloading a shotgun?
Otherwise I'm going out to BOC gas and renting a 6000PSI nitrogen bottle.
Posted: Fri Dec 03, 2010 12:58 am
by ilovefire
6000psi "water gun"

now thats something i want to see
Posted: Fri Dec 03, 2010 1:09 am
by Technician1002
ilovefire wrote:6000psi "water gun"

now thats something i want to see
Power Washer.. The high pressure tends to break up the stream very early.
Posted: Fri Dec 03, 2010 1:19 am
by ilovefire
Technician1002 wrote:ilovefire wrote:6000psi "water gun"

now thats something i want to see
Power Washer.. The high pressure tends to break up the stream very early.
maybe not so much if you had a strait pipe instead of the fanning nozzle but im sure it would to some extent
Posted: Fri Dec 03, 2010 1:47 am
by Zeus
I thought it might not work, I'll try once I get a fridgy and make a "normal" water gun.
~600PSI should be fun.
Posted: Fri Dec 03, 2010 1:53 am
by ilovefire
Zeus wrote:600PSI should be fun.
if properly handled it would be quite so!
Posted: Fri Dec 03, 2010 2:10 am
by jackssmirkingrevenge
When I visited Bovington there were some interesting cutaways of the
Churchill Crocodile "water gun"

mechanism, I think I have some photos, will try to dig them up when I'm home.
Posted: Fri Dec 03, 2010 2:15 am
by ilovefire
jackssmirkingrevenge wrote:When I visited Bovington there were some interesting cutaways of the
Churchill Crocodile "water gun"

mechanism, I think I have some photos, will try to dig them up when I'm home.
yea that would be sweet thanks
Posted: Fri Dec 03, 2010 3:48 am
by ThornsofTime
Sooooo yeah, just caught up with this thread.
BE EFFING CAREFUL... "water guns" tend to be a bit on the unsafe side to start with.
I would NOT recommend a "water tank" on your person (read-backpack).
Cool idea and all, I just think it to be a bit of a waste. After all, cant shoot "water guns" in too many places now can we. I mean... I dont want my car "wet" or my house "wet"... Then again my dog could use a "bath"... FULL STEAM AHEAD!!! (and post schematics)

Posted: Fri Dec 03, 2010 3:53 am
by ilovefire
ThornsofTime wrote:Sooooo yeah, just caught up with this thread.
BE EFFING CAREFUL... "watter guns" tend to be a bit on the unsafe side to start with.
I would NOT recommend a "watter tank" on your person (read-backpack).
Cool idea and all, I just think it to be a bit of a waste. After all, cant shoot "watter guns" in too many places now can we. I mean... I dont want my car "wet" or my house "wet"... Then again my dog could use a "bath"... FULL STEAM AHEAD!!! (and post schematics)

yea well im still not sure if i will make one its just been something iv always wanted to do but because of cost and other issues im not sure if it will happen in the near future

Posted: Fri Dec 03, 2010 4:11 am
by ThornsofTime
Well, just make sure you stay smart, and dont let lack of money temp you into cutting corners. If you MUST have one, do your research. Also, usually a good idea to involve more than one person on builds like this. Hopefully, more brain power = more safety.
A "one-way" valve will be a MUST between the "water tank" and "water gun"
like this one
http://amaramaengineers.tradeindia.com/ ... estor.html
Posted: Fri Dec 03, 2010 4:33 am
by ilovefire
ThornsofTime wrote:Well, just make sure you stay smart, and dont let lack of money temp you into cutting corners.
maybe once i have a job and some money to blow i will give it a go but in the financial situation im in now i dont think i would even be able to afford an unsafe "water gun"
ThornsofTime wrote: Also, usually a good idea to involve more than one person on builds like this. Hopefully, more brain power = more safety
no offense to the people i know but i cant see them coming up with anything safer then i would make, also i cant see them being bothered to make one, plus i doubt my dad would aprove anyway

Posted: Fri Dec 03, 2010 9:48 am
by Technician1002
If I was going to build one, I think I would not use a valve except as a safety and use a positive displacement pump that is fully sealed to prevent leaks. I have a small 12 volt DC vane pump from Micropump that would do the job nicely. The pump is magnetically coupled to the motor so it can't leak.
For more than forty years Micropump has lead the way in miniature fluid handling systems. Back then we introduced magnetic drive gear pump technology, the first and most reliable "leak-free" pumping solution. Today, Micropump continues to innovate introducing new designs and fluid systems and we remain the industry source for sealless, miniature, low flow pumps for stand alone and OEM applications.
Low flow means reasonable pressure on a small waterjet.