My APH/CPH

Build a homemade water gun or water balloon launcher and tell us about it.
Fredcompany
Posts: 198
Joined: Thu May 13, 2010 7:09 pm

My APH/CPH

Post by Fredcompany » Fri Jun 04, 2010 8:33 pm

I don't have a picture of my APH, but I do have my (not to scale) design. I moved some pieces around to make it into a CPH.
Pics:
Image
That's the design I currently have, with a balloon CPS PC.
I was thinking of rearranging it to this:
Image
Would this work better, be about as good, or make it worse?

Also, any tips for what to make a PC case out of, or at least what size for a balloon PC?

EDIT: I would make the pics smaller, but I don't know how on this forum. Could someone change it, or tell me how to change it myself?
I'm a dude

User avatar
JuchTurtles
Posts: 478
Joined: Sun Jul 19, 2009 5:52 pm

Re: My APH/CPH

Post by JuchTurtles » Fri Jun 04, 2010 9:09 pm

Make a PVC case and follow the design of SuperCPS.

This design should work. What are you going to use as a nozzle and what kind of pump?
The name's Juch, just Juch.
Also known as Commander JuchJawsTurtles, commander of the C0BALT TiDE team in The Ocean Volcano Union.
SPLASH! You're dead!

Fredcompany
Posts: 198
Joined: Thu May 13, 2010 7:09 pm

Re: My APH/CPH

Post by Fredcompany » Sat Jun 05, 2010 10:13 am

I've got a homemade pump which works pretty well, but needs some epoxy to seal it.
The problem with making a PVC case is that I don't have much PVC, and even less money.
What about the size of the PC case? I've been slightly scared of blowing it up any larger than a water balloon without a case, just in case.

EDIT :P ut the two posts together.

The water balloons broke, due to the fact that they were not on a hose barb, but a connector with some corners. One corner broke through 25 balloons, so I thought it would be easier to replace the chamber than fix it.

So my APH now has the CPH layout, and is now a CPH. I don't have as much of a problem with the case now, because the PC is made from bike inner tubes (3 layers until I get some more) and I can put them in a section of drainpipe.

So here are some pictures: (I'll link to them, as I don't know how to make them smaller - they're too big).

The whole gun:
http://i907.photobucket.com/albums/a...y/DSC01840.jpg
The nozzle:
http://i907.photobucket.com/albums/a...y/DSC01841.jpg
The end of the PC with its wooden bung:
http://i907.photobucket.com/albums/a...y/DSC01842.jpg
The other end of the PC (I used rubber bands until I get another tubing clamp):
http://i907.photobucket.com/albums/a...y/DSC01843.jpg
And here's a video:
http://s907.photobucket.com/albums/a...t=MOV01847.flv

Can anyone tell roughly what output this is? I think it's about 5x, but that's a very rough estimate.
And how much should I be able to safely pump up the PC without it exploding? I pump it till it's about 2.5 inches wide. Can I do more? And how many layers of bike tubes should I have on the PC?
Last edited by Fredcompany on Sat Jun 05, 2010 7:55 pm, edited 1 time in total.
I'm a dude

User avatar
Silence
Posts: 3825
Joined: Sun Apr 09, 2006 9:01 pm

Re: My APH/CPH

Post by Silence » Wed Jun 16, 2010 11:50 pm

For some reason, your links got shortened... the ellipses need to be replaced by c279/Fredcompan

However, I can't figure out the URL for the last link, which also got shortened, so I'll just comment on the water gun itself.

Construction looks solid, but as you said, you'll want to throw a case over the rubber tubing. I believe you can get away with a case that is larger in diameter than the tubing itself, even when filled - however, it's not going to help stop the tubing from exploding. To do that, stop pumping once the expanded part of the tubing spans the entire length, or maybe a little less - if you're really cutting it close, you won't be able to pump much more water because there's nowhere else for it to go before the bladder ruptures.

You might not need pipe as strong as PVC for a case, but I'm not really sure. I believe Ben or C-A 99 may know.

You can probably layer as many bike tubes as you want or can, but I would only do so after installing a cover.

Fredcompany
Posts: 198
Joined: Thu May 13, 2010 7:09 pm

Re: My APH/CPH

Post by Fredcompany » Thu Jun 17, 2010 7:11 pm

I have a piece of drainpipe for a cover, but the problem now is attaching it to the copper pipe.
The problem with layering on bike tubes is that it's already hard to put on new tubes, because I started with mountain bike tyres, and so there are no larger sizes of tyre available (other than car and tractor tyres).

Speaking of tractor tyres, I have a large section of one. Would it be worth trying to make a hydropower-style system out of it? (It's about 1/4" thick)
I'm a dude

User avatar
Silence
Posts: 3825
Joined: Sun Apr 09, 2006 9:01 pm

Re: My APH/CPH

Post by Silence » Thu Jun 17, 2010 8:08 pm

How much range are you getting? Are you satisfied with it? If not, you could just redo the bladder, since old tire tubing is (or should be) free.

I'm not impressed with rubber diaphragms. There's too much force pushing the plate and rubber apart...my Orca had maybe 30 steel screws and a very solid frame holding everything together, and it still wasn't too powerful. Sorry. :/

User avatar
C-A_99
Posts: 1502
Joined: Tue Aug 01, 2006 11:09 pm

Re: My APH/CPH

Post by C-A_99 » Thu Jun 17, 2010 8:50 pm

There are good reasons that BBT stopped using diaphragms and lots of stress on the PC case was one of them. And since this is a homemade, it will be even more difficult to securely hold a rubber disk steady. (Since you can't simply manufacture a case for it.)

The strength of the case depends on what you want to do with it. If all it does is hold the bladder together and prevent scratching, then you just need the case to be strong enough so that it'll hold together. (i.e. won't get bent around from use.) However, if you want to use the case to stop the bladder from expanding beyond a certain size, you may want to use at least sch. 40 cellcore pipe. You shouldn't ever need to use pressure rated pipe though. However, if you go with this approach and frequently pump to the case's capacity/expansion limit, the bladder is very likely to wear out a lot faster.

A third approach is using limited diameter pipe to force the bladder to expand lengthwise farther. LRT tends to rupture from higher diameters first before from lengthwise expansion, so using a 3" or maybe even a 2" tube wouldn't be a bad idea. I'd go with something in between (like some kind of drainage pipe) since 2" is pretty small and will considerably limit the amount of water the PC can shoot out.

Of course, that's just for cylindrical bladders. I haven't much clue on how to build a good case for spherical bladders so far as I never looked into it. I don't even know if pipes are a good idea for spherical cases, though they may work if they have enough diameter.

User avatar
cantab
Posts: 1492
Joined: Fri Oct 19, 2007 1:35 pm

Re: My APH/CPH

Post by cantab » Thu Jun 17, 2010 9:23 pm

I've never tried, but plastic mixing bowls might work as PC cases for spherical or diaphragm chambers.

I wouldn't advise trying to use the tractor tyre piece. The problem with that - and to be honest with bike tubes - is they don't stretch as well as balloons or LRT.
I work on Windows. My toolbox is Linux.
Arsenal:
Super Soaker: XP215, 2xXP220, Liquidator, Aquashock Secret Strike M(odded), Arctic Blast M, CPS1200, CPS2100, SC Power Pak, 3l aquapack, 1.5l aquapack
Water Warriors: Jet, Sting Ray M, Shark, Argon M, Tiger Shark, PulseMaster
Others: Waterbolt, The Blaster, Storm 500, Shield Blaster 2000, generic PR gun, generic backpack piston pumper (broken), 3l garden sprayer M, 10l water carrier:

Fredcompany
Posts: 198
Joined: Thu May 13, 2010 7:09 pm

Re: My APH/CPH

Post by Fredcompany » Fri Jun 18, 2010 6:13 pm

The bike tubes work, but the only problem is that I need to get some more to make it have a decent amount of power.
I'm a dude

User avatar
Killi101
Posts: 89
Joined: Sun May 30, 2010 11:30 pm

Re: My APH/CPH

Post by Killi101 » Mon Oct 18, 2010 3:37 pm

could you re upload the pics, i want to know how you used the bike tubes instead of LRT, i want to make a backpak cps myself. how much does the bike tube expand under pressure?
PC capacity?
Water:
dont like drinking much
like to throw it at people

User avatar
-G-JiV-
Posts: 350
Joined: Sat Oct 09, 2010 8:10 pm

Re: My APH/CPH

Post by -G-JiV- » Tue Oct 19, 2010 6:38 am

WHy you do not use a cylindric PC ? From my own experience I know that is is easier to find a straight expanding ruber tube and a pipe of perfect size than finding a tube balloon and a fitting sphere...It is also easier to seal a pipe because it got two ends which can be closed easily, but you will need a sphere with a whole, may also consisting of two parts so you can open it, and isome people also say that clindrical PC have more power than spherical ones...

I could show you some pictures of my CPH, it uses a cylindrical PC(sry it got three PCs...)and it got bid power and capacity and never broke down.

User avatar
Killi101
Posts: 89
Joined: Sun May 30, 2010 11:30 pm

Re: My APH/CPH

Post by Killi101 » Tue Oct 19, 2010 5:53 pm

he is using a cylinder pc, it is just not giving him enough power
Water:
dont like drinking much
like to throw it at people

Fredcompany
Posts: 198
Joined: Thu May 13, 2010 7:09 pm

Re: My APH/CPH

Post by Fredcompany » Tue Oct 19, 2010 7:29 pm

The bike tubes do not give enough power because the volume of water in them only (roughly) triples. In LRT the volume of water (I think) is multiplied by about 24pi (8x wider and 3x as long) (that was a random quick bit of working out - I have not idead if 24pi is right.) This problem may be more due to me being slightly scared of it exploding (haven't fixed the PC case yet). But if I pump it up more, the bike tube might exert more force on the water. This would mean it isn't much of a CPH, more like a IPH (Increasing Pressure Homemade), as the pressure increases as it holds more water.

Also (I don't know if this affects performance), bike tubes do not expand in width and then along the length. They expand along the whole length. It is like the difference between pumping up a bike tyre and blowing up a modelling balloon. This leads me to think that modelling balloons may be more suited to CPS making. This also means you only have to seal one end, as they are closed at one end anyway.

I had a revelation in a Chemistry lesson though. The tubing they use to connect the gas taps to bunsen burners seems to be very similar to my idea of LRT or gum rubber tubing. Its elastic properties are not used in the lab, so I have no idea if it would work, but I might enquire where my school gets the tubing from.

P.S: This is all speculation.
I'm a dude

User avatar
Killi101
Posts: 89
Joined: Sun May 30, 2010 11:30 pm

Re: My APH/CPH

Post by Killi101 » Tue Oct 19, 2010 8:01 pm

now that you say it, it is pretty elastic, the gas pipe i mean. but where would you get them? but what range are you getting?
?
Water:
dont like drinking much
like to throw it at people

User avatar
zeda.beta
Posts: 683
Joined: Sun May 03, 2009 10:49 pm

Re: My APH/CPH

Post by zeda.beta » Wed Oct 20, 2010 4:53 am

I thought he posted a range of around 35 feet, but that might just be me. I've been planning to make a CPH with modeling balloons as the pc, but never got around to it. BTW, the gas tubing you guys were talking about probably doesn't expand very much. It's designed to prevent backflow, not store pressure.
I reject your reality and substitute my own.
Quack damn you.

Locked