Shotgun-Style Homemade

[Ben]

Welcome to SSCentral rock force! I have upgraded your membership account.

Originally posted by death angel@May 28 2005, 08:03 PM

Isn't laminar flow increased if the if the route water takes from the PC out the nozzle as straight as possible ? Because I noticed on most designs the PC's are facing downward, instead of facing toward the nozzle. Is there some reason for this type of design? :unsure:
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Yes, though as Duxburian explained, the air always floats on top. There's no magic here. I'd suggest reading my TechLog entry on Highest Performance Design in homemade water guns for more information on how this can be done in air pressure. The APH PC design is simple to make and is why I included it - the APH is a "beginners" homemade.

Also, there is nothing inside of the pump except for the aluminum rod with a seal on the end. Electrical tape wrapped enough around the rod will work okay. O-rings usually are either too small or don't move fast enough. What I would suggest as the best homemade pump is one taken from an unused water gun as they have good seal and move freely.

You also would have to seal off one end of the Tee that connects to your stock or whatever that is. Otherwise it will fill up with water, make your water gun work less often, and weigh a lot.

[rock force6]

So if I took a pump from an old SS and stuck it inside the pvc then it would work? Thanks for the help everybody, BTW.

EDIT: Never mind, I think I get it. As the pump seal moves back it sucks the water into the space thatr is created, and when you push it back in it pushes the water through the second check valvle, right? Here's a picture of how I think it works.



One question though- Do I run a flexible tube from the bottom of the reservoir to the start of the first check valve? If not, how do I get the water from the reservoir to the pump?

Thanks.

[CPS]

that looks cool, but the handle needs to be bigger

[Ben]

If you do not let gravity feed the water down into the check valve, you'll have to use a tube to suck up the water from the bottom. I don't really see any advantage in having the reservoir point down, so just make it point up and avoid that problem.

You're correct on how the check valve setup works also. B)

[rock force6]

The reservoir is pointing down so it can be attached to the bottom of the butt stock. You said that there are no advantages to having it point down, but what about disadvantages. If I can, I'd like to keep it facing down. So would the tube go until the beginning of first check valve? Thanks.

[Ben]

Yes, a tube would have to be used to feed the water into the rest of the water gun (as I had said earlier).

There also is nearly no need for a stock! Recoil isn't very heavy, especially if you have an included reservoir, and you could use the reservoir as a stock. The stock is more than likely going to be an annoyance. I've never been in a situation where one would be useful, even if it was just to aid in aiming (which doesn't make sense in water guns because the shots have duration anyway).

Make the stock if you want, but I really do not think you'll like it very much.

[rock force6]

I'll probably take out the stock and instead of using a 45 degree adapter I'll just use a straight one for the reservoir.

[Ben]

Please remember, that with a straight reservoir you'll have to tilt the water gun down for all of the water to go into the water gun. However, you'll likely only have to tilt on the last shot of the reservoir. Please also consider making your water gun have a removable reservoir so you could use a reservoir or a backpack. B)

Pepper's homemade water gun has a good reservoir design you may want to look at.

[rock force6]

If I took a female adapter and a 2 liter bottle would that work?

[Ben]

Of course not. That's not even close to fitting. Just get some PVC and a threaded male adaptor to make the reservoir and have a threaded female adaptor for the water gun.