18V cordless drill-powered pump - what sort of flow possible?

[Garagebanjo]

So I had a crazy thought for a fun project: a cordless drill-powered water gun.

Background:

For years I have been tormenting young kids at a huge extended family annual summer picnic using a garden sprayer as a water gun. Actually 2 of them, both strapped onto my back. Pumping up the sprayers fully with air allowed me to chase the little rugrats around, firing with both hands, targeting sometimes 2 kids at once. No pumping required until I ran out of air. It's always a hoot!

The downside of a garden sprayer as a water gun is that it's stream is weak. The kids are armed with the plastic super-soaker toy water guns and they generate a strong stream, albeit for only short while until they run out of water. The nice thing about a weak streamed garden sprayer is that I can spray for a long time. So it's fun to fight and evade the super soaker armed kids until they run out of water and then I close in for the kill with my twin tanks still nearly full.

Most recently I tried to think of how I can improve the force of my water stream whilst still avoiding the need to pump while on the run.

Could a water pump powered by a cordless drill (18V typical handyman model) be powerful enough to send a good stream of water? I'll still have a tank strapped onto my back so the amount of available water won't be an issue. Battery life won't be an issue either as I bet the drill could run for a long time.

But what kind of volume or water pressure could I get?

Ideally, I'd like to get quite a strong blast of water! Like maybe 10- to 20% of a pressure washer! (I could be dreaming of course.).

Am I nuts?

Anybody with small pump experience care to comment?

(I have a few months to build this contraption.)

 

[G_P]

I would use a cheap inline 12v fuel pump. It will be much more compact than a drill with a pump in the chuck and will generate more pressure. You could even make a "gun" by putting a momentary pushbutton switch on whatever you are using as a nozzle.

 

[CJM8515]

Super soaker made a super duper water gunin the late 90's with a similar idea. It was a giant backpack with a 2 gallon capacity and you pumped a lot but it sure lasted and was like 10x the power of the handheld ones.

Id build something similar to that. What makes a super soaker work so well is the pressure the water is under.

This is what I had, I cant remember why its long gone now, maybe broke IDK.. http://www.isoaker.com/Armoury/Analysis/1993/super_soaker_ss300.php

 

[rice rocket]

I would use a cheap inline 12v fuel pump. It will be much more compact than a drill with a pump in the chuck and will generate more pressure. You could even make a "gun" by putting a momentary pushbutton switch on whatever you are using as a nozzle.

Walbro or Bosch?

 

[dreamingmuscle]

I used to fight my kids with one of those old silver 2.5 gallon extinguishers. The ones you put water in and pressurize with a schrader valve. You can run and hose for about 5 minutes and reach out about 20 feet.

Glen

 

[thieltech]

the in tank fuel pump would work excellent in a back pack style !

use an old drill for the gun and take motor out and install tube for spraying water .

plus then the batterys built in gun and u can use trigger to activate pump in the back pack tanks

just run small wire and hose to back pack!

 

[Kracin]

best thing for you would be to buy a utility pump. typically they come with a pickup hose, you can buy them in a 12v version. you want the 12v version because then you can use a 12v power tool battery pack for the power. wire the pack, a switch and the pump together. and put the pickup of the pump into a 5 gallon yard sprayer backpack.

the exit of the pump can be just a long stick with a high pressure yard nozzle on the end. attach the switch (try to find water tight!) to the base of the stick/nozzle and you are in action quick and simple. you could probably piece it together for around 50 bucks if you buy used stuff.

this pump
http://www.northerntool.com/shop/tools/product_200606589_200606589

in this pack
http://www.northerntool.com/shop/tools/product_200456735_200456735

and this gun.
http://www.northerntool.com/shop/tools/product_200587683_200587683

with a switch like this
http://www.amazon.com/dp/B00PUXULO2/?tag=atomicindus08-20

and hook up a 12v tool battery to it all. mount the switch behind the trigger of the gun. and boom. killer water gun ready. (or a small lightweight car battery, which may provide better running with a small pump running like that, they sell compact car batteries that don't weigh much also, depending on how high your fun budget is)

 

[Garagebanjo]

Awesome advice guys. I hadn't thought of using an inline pump.

Lots of ideas going through my head at the moment!

 

[larry_g]

kraCIN RECOMMENDS A PUMP THAT ONLY HAS 6' OF HEAD. THAT IS GOING TO BE A WEAK STREAM. YOU NEED A PRESSURE PUMP, NOT A TRANSFER PUMP.

LG
NO NEAT SIG LINE

 

[Kracin]

kraCIN RECOMMENDS A PUMP THAT ONLY HAS 6' OF HEAD. THAT IS GOING TO BE A WEAK STREAM. YOU NEED A PRESSURE PUMP, NOT A TRANSFER PUMP.

LG
NO NEAT SIG LINE

it's an idea for what to look for. 6' of head. he is only going to be running enough hose to be at the end of a gun in front of him... hes not pulling water out of a well. not to mention he isn't trying to shoot water like a firehose, it's for a childs waterfight...


also, all caps is terrible forum etiquette....





fyi, heres a video i found of someone using one in conjunction with a nozzle you can use on the end of the hose with a small pump (375gph [300gph at 10ft head]. the one i listed was 475gph, so more).

instead of being a jackass, be supportive. i like your sigline btw...

 

[malibu101]

I too like the fuel pump idea. A 12VDC fuel pump for a car will generate a very good amount of pressure and probably enough flow. Running it at 18VDC shouldn't be a big deal.

And as was said, I have personally found out that a water fire extinguisher is a cool toy too.

 

[Kracin]

I too like the fuel pump idea. A 12VDC fuel pump for a car will generate a very good amount of pressure and probably enough flow. Running it at 18VDC shouldn't be a big deal.

And as was said, I have personally found out that a water fire extinguisher is a cool toy too.

a fuel pump would be good, but the volume of water moved might be a lot less than the linked pump. a walbro 255 flows 255lph, or 66gph. it's quite a bit less flow than something that can move 6-7x that number, and pressure is created when volume is reduced (nozzle). considering how cheap you can find fuel pumps on amazon, it would be worth a shot to test and see how big of a stream you can shoot also. but you might end up shooting a really thin stream to get the distance. remember, cars needs pressure not flow (in gallons transfered quickly.... minus top fuel drag cars lol). so it's a bit of an opposite end of the spectrum kind of thing with a transfer pump vs a fuel pump