SpudFiles

if i was to make a "water gun" using a blow gun as a trigger would i be able "clean" it out on a regular basis with shellite or petrol without destroying the seals to a point that they will leak?
(sorry for the randomly placed quotation marks)

I would think that any alcohol based solvent would eat away the lube in the blowgun. Not really an issue if you're willing to take it apart and re-lube it after "cleaning", but that kind of defeats the whole "cleaning" process. May as well just do a standard "disassemble, clean, lube, reassemble" job.

I would also be worried about how the solvent would react with the rubber in the sealing o-rings. Might get some deformation or dry out the rubber and eventually need to be replaced.

Long story short... I may be wrong, but I wouldn't do it.

would a small ball valve be able to be "cleaned" without effecting the seals or would it have the same affect?

"water gun" eh

What about this?

jackssmirkingrevenge wrote:"water gun" eh

What about this?

yea you get the gist, but with a user id like mine what else would i want to try make other than a water gun
but i think at the moment its just an idea ill probably have to get a job before i start actually playing around with "water guns"
but anyways im not sure how well that handle would be any good at say.. the same pressure as butane? (not that i would use butane to pressurize a water gun, but maybe a "water gun") lol

Blow guns have insufficient flow to be of much use in a *water gun*. The water gun community tends to prefer ball valves, and rightly so - they're readily available, reasonably priced, and offer very high flow coefficients while tending to keep the flow laminar. This is essential if one is aiming for a coherent stream with decent range. Many ball valves will have PTFE seals, and a half inch model usually costs less than $10. These seals are, as you might guess, completely impervious to most chemicals at room temperature, and will have no trouble whatsoever with any volatile hydrocarbon you may use for *cleaning*.

You can, of course, buy pneumatically or electrically actuated ball valves, but it's generally cheaper (and quite easy) to build your own actuator.

Also, why would you use butane? Propane tanks are cheap, readily adapted to NPT fittings, and run much more useful pressures.

I'm suspicious of your intended use. I can only recommend using clean water in your watergun. Cleaning with solvents is not necessary. Use a commercial detergent.

If you are intending to make a flamethrower, this is the wrong forum.

LOL your nickname makes you even more suspicious

Actually the last time I checked "water guns" are legal to own and use for non-defensive purposes in the US, unless prohibited by state or city laws.

I'd recomend a ball valve also if for no other reason than they do not fail catastrophically in terms of unexpected leaks...


Don't use a plastic chamber.

Technician1002 wrote:I'm suspicious of your intended use. I can only recommend using clean water in your watergun.

Anyway... I wouldn't recommended using butane to pressurize anything if you want substantial flow, since it has a measly vapor pressure of about 30psi at room temp. Not to mention the dangers of using a flammable propellant gas, which has also been known to kill people who inhale too much (somebody died a few years ago in my school from inhaling butane). If you're not willing to pump up your own pressure to power this water gun of which you speak, I'd go for nitrogen or argon, maybe CO2. They all have very high vapor pressure, and are non-flammable, a definite bonus if you're going to power your water gun with them.

But you could use butane if you're counting on heating up the system by some means, since its vapor pressure increases very rapidly with temperature....

I find that butane only works for a springer type "launcher". I'd use a 1/2 BV for water guns, be cafeful of course as these water guns cause a permanent stain if you use them like I do.

Never ever use air to pressurize any water gun.

Have fun.

first of all if any moderators do not like "water guns" i am happy for them to remove this thread

DYI wrote:Blow guns have insufficient flow to be of much use in a *water gun*.

well the nozzle would be less than 1mm so flow isnt really a problem, but i wouldnt want it to start leaking on me because i wouldnt want to get "wet"

saefroch wrote:If you're not willing to pump up your own pressure to power this water gun of which you speak, I'd go for nitrogen or argon, .

would it be safe to pressurise it with air? i know that people do do so and i can see why it wouldnt be a problem most of the time but is there a chance that it could catastrophically fail?

edit:

Zeus wrote:I find that butane only works for a springer type "launcher". I'd use a 1/2 BV for water guns, be cafeful of course as these water guns cause a permanent stain if you use them like I do.

Never ever use air to pressurize any water gun.

Have fun.

springer type "launcher"?
and yes air is defiantly not what i want to use, for obvious reasons

I would not use air to pressurize any water gun that had been cleaned with solvents. Use something that can not create a flammable mixture in a confined space.

yes that is exactly why i wanted to use butane, but will it be able to propel water to maybe 2-3m out a .75mm nozzle?

Well for one, you would need an ignition source to ignite any flammable mix, which as we all know can be quite an issue, but it shouldn't be overlooked especially if fumes leaking out are lit, then allow the flame front to go back into the chamber. Which is why all water guns that may deal with flammable solvents that I know of use argon or nitrogen tanks.

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.