The Best Soaker for River Rafting?

[waterzooka]

Good point on the tubing size. I was thinking along the lines of a hydraulic brake systems, but they have very little flow.

My first design utilized 1/2" pvc instead of braided vinyl tubing. I think returning to that idea would be best. As long as the tubing ID is larger than the Nozzle Orifice, the flow would not be restricted.

I use Visio to create my pics/diagrams. I created a bunch of pvc fittings a while ago. Now, when I want to make a new design, I just put the different pieces together. I can set the transparency level quickly, so creating the internal drawing was simple.

[Ben]

I wouldn't even separate everything with the pipe inbetween. In my opinion, it would be best for both flow and space to just put the second chamber right at the end. The length would be an issue, but you can reduce the length by increasing the diameter of both chambers. You can still get the same amount of multiplication with larger diameter pipes, and the water gun would be far shorter. Finding O-rings of larger sizes is difficult. Piston seals would work well at those sizes however.

[Silence]

Hmm...I guess I get it, and thanks for detailing the piston in the wider tubing. I can't wait to see the results!

Definitely something that somebody should have thought of before this. Perhaps the design can be adapted to regular homemades...I'll have to work on that, if you don't mind. Great job!

Yeah, braking fluid tubes are tiny. I'd say they're no more than 1/4"-1/2" in diameter, if I remember correctly from when we replaced our van's tube.

If both diameters really can be increased for a shorter pump length, then that would be very nice. I look forward to the completed gun! I might even buy it from your store if it's available and if I'm allowed to.

The cost would likely be fairly high, if you were to buy such large parts--for example, large tubing, large barbs, and large Jubilee clips. Rubber cups might be expensive too, but Ben will have to verify that.

[waterzooka]

Yeah, I have to agree, removing the tubing, elbows and connectors would make a much cleaner design.

This is what I what thinking of a couple of days ago. All that is needed is a bell reducer. It would still need a bleed valve, but that would be simple. With 1-1/4" and 2" pvc the overall length (compressed) is about 5 ft. Not unbearable, just big. Maybe the competition would run just from the sight of my Long Range Waterzooka! Here is a pic of a compressed and half-compressed gun.



I'll do some calculations with larger diameter pvc and share my results. Larger pvc pipe and fittings are expensive, but still worth a try. And I do have a good source for o-rings. (If I buy in bulk)

And to answer your question, SilentGuy, absolutely. When I offer the Waterzooka LR© online, you can be the first customer. Maybe I'll even donate a few Waterzookas to the SSCentral Staff for evaluation.

[Ben]

That's the design I think would be best! I'd love to see a water gun like that.

One thing I would recommend for larger diameters would be piston cups. These are fairly cheap and seal well. They probably are not as cheap as O-rings, but they are much easier to work with. You can order them online from McMaster-Carr (search for piston seals and scroll to the bottom to find the Buna-N piston cups). I'm afraid that someone might have trouble moving the piston with these however. I was working on a small toy gun that shoots darts that uses a spring and a piston, but I think I'll use those parts for a test water gun with the piston seals. Before I was surprised with how well they seal. If it works well, you might want to consider changing your design.

For the Waterzooka LR however, I think stepping up from 1 1/2 inch PVC to 3 inch PVC would be a good middle ground. Those seals would cost about $11 per water gun not in bulk. My initial thoughts for this was to step up from 2 inch PVC to 4 inch PVC, but the piston seals are more expensive at those sizes.

So, I'll get back to you on the piston seal water gun I can construct... this might be a very good idea.

Can you provide any tips on constructing seals with O-ring in PVC? I realize this might be revealed in your product, but I never was able to make good piston seals from O-rings. Would definitely benefit all here.

[Silence]

That's amazing! You've got a steady stream of ideas going, and it will get you far. I guess the length was the only limiting factor and reason to split the two parts, but this can't be too bad, at least with larger diameters. A system definitely needs to be used in a PPP (PVC piston pumper) that uses a reservoir, if you don't mind.

I definitely suggest adding a system of some kind where a "turret" on the wider part can clamp onto some type of stand. Either that, or seriously consider wider tubing. The length really isn't so bad as the fact that the center of gravity would be very much near the front, but a mount of some sort would solve that problem.

And either way, this is definitely something that you won't want to have to dip into the water before every shot. (Or every few shots, depending on how long your shots last.) So the tube system would definitely be a good idea, perhaps using a tee in front with a bushing in two of the legs.

Then again, the system doesn't have to be that long, even with smaller diameters, if you don't mind having to refill more often due to a smaller capacity. IMO, the ideal homemade river gun would incorporate a small Waterzooka LR design with an intake tube for water. No, you couldn't keep a constant stream, but I'd like it more. Especially if it had instead of tubing an actual reservoir built in.

You might also want to consider building a ball valve or something into the part between the two plungers. Otherwise, you never know what type of organic material could be residing inside. A bit paranoid, I suppose, but I personally would be more comfortable with putting fresh water in there every time you use the gun and emptying it out in between.

[waterzooka]

I would like to address the method of creating great (not just good) seals with O-Rings for use is pvc piston water guns. I have glanced at the other designs posted here I believe I could shed some light on airtight, low cost piston assemblies.

However, as Ben pointed out, I would be handing over some of my hard work at no cost. (Which I'm not entirely against...because I have a small dream about "open source" water guns) So, I'm in a quandary.

As I mentioned in another post, my goal at www.waterzooka.com is not to become a millionaire, but rather, just to cover my costs and provide the general public with easy to follow instructions on how to build cool stuff. Or maybe even provide completely assembled water guns for those that don't want to get their hands dirty. (Just wet!)

So, I was thinking about offering a 20% discount to all members of SSCentral for Instructions, Supplies, complete guns, etc. I'm not sure if this idea is inline with the spirit of this forum, so I am open to suggestions.

I will, however, share this. My piston design is made of standard pvc fittings, does not require cutting any grooves and does not require tape. One of my first pvc piston water guns that I built almost 20 years ago still performs like a champ today!

And on another note - Thanks for you encouraging post SilentGuy. My passion is designing and building. (Just about anything) So, I get consumed with ideas and spend what little extra time I have in the garage creating/building.

I have been reading through the other posts on APH (Air Pressure Homemades) and I can't wait to build one or two. I will share designs and photos along the way.

[Silence]

Well, I would still love to see the end result!

Hopefully, though, I'm speaking on behalf of all the membership when I say that a 20% price reduction is unnecessary. Really, all the people here are just regular people who are interested in soakers, often building them. There's really nothing special.

It sounds like your system might be like Drenchenator's, where he attaches two rings of CPVC to a rod for a permanent seal, although yours might use PVC on an endcap--I'm just guessing, of course. I know I will use flat-sided O-rings in the future as opposed to round ones. Anyway, I'm not trying to pry the information from you, just wondering. Good luck with the sales!

[waterzooka]

The pistons design I use for my waterzooka is built with 1-1/4" and 2" pvc. I was hoping to use the same design for an APH, but the piston size is much smaller. (1/2" pvc) So, I'm still working on a clean design for a piston pump on a APH. I have some ideas, but nothing seems to be an improvement on the designs already posted.

For a larger piston, here is what I do to make a perfect seal:
-The correct/type size O-Ring
-Lots of waterproof or water resistant grease
-A good section of pvc pipe. (When pvc is shipped in bulk, they use metal bands or straps to hold the bundles together. Some of the pipes on the outside of the bundle get squeezed and deform the inside of the pipe. No big deal for plumbing, but definitely a big deal for piston pumps. Make sure to grab a pipe from the middle of the bundle and look down the inside to make sure the pipe is not deformed.)

The trick for keeping the O-Ring in place is quite simple. I have shared this with a few of my friends and their response has been "doh", "of course" or "why didn't I think of that".

I make a 24" plunger from 1-1/4" pvc and place it into cylinder of 2" pvc. So, cut 22" and 2" sections of 1-1/4" pvc. Slide the O-Ring over the 2" section. Glue a cap on one end of the 2" section and a coupler on the other. This traps the O-Ring between the cap and the coupler. Now, glue the 22" section into the coupler. That's it! Of course you will need to put another cap on the other end, but do that after the final assembly of the waterzooka.

[Silence]

Very nice. I guess Drenchenator's method is cheaper since CPVC is very cheap (in bulk, too), but yours also works; and you can saw off a band from the coupler to get multiple pieces, less hassle, and one strong piece. Either way, my future homemades will most likely use 3/8" CPVC because no tubing is both smaller and still practical; but most importantly, as I've said, I've had enough with round O-rings. They're [nearly] impossible to work with.

Here's what I would suggest for an APH/CPH (CPHs use latex rubber tubing for constant, powerful force--hence the name Constant Pressure [System] Homemade):
- 3/8" diameter metal pump rod
- 3/8" CPVC (I'll probably have to get it either from a plumbing store or from McMaster-Carr)
- a flat-sided O-ring, with a 3/8" ID and a 5/8" OD
The pump tube is, of course, 1/2" Schedule 40 PVC.

So it's practically an exact replica of Drenchenator's idea, once you think about it. Oops. It was a subconscious thing, and thank you both for the ideas.

And by the way, even if somebody doesn't feel it necessary to use PVC/CPVC to hold the O-ring in place, it's still a good idea to use the specifications suggested in the SSC pump guide: 3/8" aluminum rod, 3/8"-5/8" O-ring, and electrical tape. Never, and I repeat never, use a round O-ring.