My CPH concept

Homemade water gun threads that are notable.
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cantab
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Re: My CPH concept

Post by cantab » Fri Jul 03, 2009 12:23 pm

Very impressive. It's great to hear success with a balloon pressure chamber, seeing as how McMasterCarr is no good outside the USA. A homemade with an onboard reservoir is good too.

It does sound quite heavy. Are the large pipes pressure rated? If so, switching to DWV would lighten it. Then again, I've never actually weighed my CPSes - though I think isoaker has weights.

Two criticisms I would make. That bit of tubing from the reservoir to the pump intake looks vulnerable. And I'd used the Tiger Shark, which similarly has something rearwards of the main hand grip, and don't like that.
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:

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captianfear
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Re: My CPH concept

Post by captianfear » Fri Jul 03, 2009 7:10 pm

I like the gun, I am intrested in the trigger. I saw that the previous design had trouble with returning the ball valve to the closed positon. Is the four finger trigger any better at closing?

@ cantab: I thought Mcmaster could ship to Canada.

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cantab
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Re: My CPH concept

Post by cantab » Fri Jul 03, 2009 8:02 pm

They may be able to. But they sure can't ship to the UK, which is where I live. If I ever make a CPH - and I'm tempted to, because it would be safer than using pop bottles in an APH - I'd have to go with balloons.

In fact, a very simple hose-filled homemade comes to mind. A CPS chamber, valve, and nozzle. A Hozelock fitting is about 3/8 inch diameter. That should be a good nozzle size right? And would also be a fine quickfill.
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:

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Fri Jul 03, 2009 8:08 pm

How many inches/centimeters back do you have to move it?
The trigger has to be pulled almost in contact with the handle. Speaking of the trigger, I must say that it is great right now. I can tap shoot with my homemade water gun, how cool is that! :p However, it still has a chance to not close completely. Just enought to start leaking on your hands from the nozzle. But pushing the trigger fowards a bit stops the leaking.
If you've been following recent events, you might know about the Water Warriors Vindicator, whose spherical rubber bladder sits exposed inside the reservoir. Is that how your water gun works, too?
No. The PC and the reservoir is separated in the middle of the gun, inside the abs pipe. The reason why I have not copied the Vindicator's concept is because my PC casing has a lot of ventilation for more performance, so it cannot be used as a reservoir.
It does sound quite heavy. Are the large pipes pressure rated? If so, switching to DWV would lighten it.
The ABS pipe I'm using is labeled Shedule 40 but has no sign of pressure rating. The reason why I choose ABS pipe is because where I buy my parts large PVC is not available in short lengths. I've just added a strap to the gun so that it is easier to use.

I've just done some testing today:

Shots per tank: 3
Pumps to pressurize: 33

Nozzle laminator + endcap drilled to 7/32":
Max Range: 41 ft
Shot time: 4 sec
Output: 350 mL/sec
This is the standard nozzle.

Image
^Nozzle laminator + endcap drilled to 3/8":
Max Range: 50 ft
Shot time: 2 sec
Output: 850 mL/sec
This one is on par with my cps 2000, but has more shot time.

Image
^Nozzle laminator without endcap:
Max Range: 27 ft
Shot time: 1,3 sec
Output: 950 mL/sec
This one ain't very practical as the water has trouble getting very far, but a concentrated stream that thick is always fun to watch and heavy hitting.

Image
^Riot Blast:
Max Range: 45 ft
Shot time: 1 sec
Output: 1200 mL/sec
The riot blast is amazing. Actually it is the best riot blast I've used yet, as it's effective range get past 40 feet. It has also the most kickback.

In the end, this gun is great, but it's weight can be annoying. Especially when compared to my CPS 2000. My homemade has some more power,capacity and versatility, but weights a lot more. All It's drawbacks makes me want to build another one. Air pressure this time. Actually, a 3D concept is on the way. :)
Armory: AS Hydroblitz (x2), MI FlashFlood, STE TripleShot, XP Backfire, XP 215, XP 105, XXP 175, Big Bottle BLaster(x2), SC Power Pak, SpeedLoader1000, SpeedLoader 1500, SpeedLoader Double-Cross 3000, CPS Splashzooka (x2), CPS 1200, CPS 1500,CPS 2100, CPS 2000 Mk2, CPS 1-3-5

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Silence
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Re: My CPH concept

Post by Silence » Sat Jul 04, 2009 3:13 am

ABS is great, from what I've read. It's obviously hard to find it in pressure-rated form, but that's not an issue for a CPS case or for a reservoir. And it's safe even if it ruptures.

Looks like the water gun fires pretty meaty streams. Looking at the riot blast, I'm curious what size bore you used. Incidentally, I'd take 1/2" over 3/4" if I were connecting a trigger to the ball valve, since smaller ball valves are easier to open.

JL, are you using 3" tubing? 4" might be more fitting, and reasonable given that you're using balloons, but of course heavier.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Sat Jul 04, 2009 6:56 pm

Silence wrote:ABS is great, from what I've read. It's obviously hard to find it in pressure-rated form, but that's not an issue for a CPS case or for a reservoir. And it's safe even if it ruptures.
I know there is a guide on this site that explains how to identify pressure rated PVC, but what about ABS? Should I look for the same writings? The ABS pipe I've used is Shcedule 40, and the fittings are DWV, but they are as thick as pressure rated PVC so they look like they can take pressure well. I was wondering about pressure ratings on ABS because they seem to be easier for me to get than pressure rated PVC, and I'm thinking about building an APH in the next few weeks.
Looks like the water gun fires pretty meaty streams. Looking at the riot blast, I'm curious what size bore you used. Incidentally, I'd take 1/2" over 3/4" if I were connecting a trigger to the ball valve, since smaller ball valves are easier to open.
Your'e right about smaller ball valves easier to open, but I've tested some 3/4" metal valves and they seem to be pretty good for triggers as well, I guess PVC valves are the hardest to open. Everything on the gun is 1/2", even the ball valve. But the ball itself inside the valve is pretty large, I think it has a larger inner diameter than the 1/2" pipe itself.
JL, are you using 3" tubing? 4" might be more fitting, and reasonable given that you're using balloons, but of course heavier.
The casing/reservoir is made of 4" ABS already.
Armory: AS Hydroblitz (x2), MI FlashFlood, STE TripleShot, XP Backfire, XP 215, XP 105, XXP 175, Big Bottle BLaster(x2), SC Power Pak, SpeedLoader1000, SpeedLoader 1500, SpeedLoader Double-Cross 3000, CPS Splashzooka (x2), CPS 1200, CPS 1500,CPS 2100, CPS 2000 Mk2, CPS 1-3-5

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Drenchenator
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Re: My CPH concept

Post by Drenchenator » Sun Jul 05, 2009 2:04 am

I keep forgetting to post; I've been reading it but not writing. Great job, JLspacemarine!

I used the four-fingered trigger because I couldn't muster enough force to pull it with one. Most guns fail to use those three fingers, so it's a great idea to employ them.

If I remember correctly (DR-3, my homemade, was disassembled completely, so I can't make a measurement) my trigger displacement was about 1 1/4", and the valve still didn't open all the way. I limited myself too much; I went for too small too quickly. You've solved that by making the trigger pull farther, and I'm kinda kicking myself when it's that obvious.

I also like the vertical pump handle. Makes the gun look very unique, and I'm sure it's quite useful--I vaguely remember reading a study that said the arm transfers more force to a vertical handle than to a horizontal handle.

Seven pounds empty weighs even more than my homemade, though yours does have a reservoir; mine lacked one. Full, your gun weights 17.5 pounds. How's the mobility without a strap when full?
The Drenchenator, also known as Lt. Col. Drench.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Mon Jul 06, 2009 5:04 am

Drenchenator wrote:Full, your gun weights 17.5 pounds. How's the mobility without a strap when full?

Well, the mobility is okay at first, but I just cant go fast attack with this gun in my hands. Actually I would not try to run with it, as it would be pretty awkward. But with a strap its okay. Also, it drains it's water pretty quickly so it becomes way more comfy to hold after a full shot. I'd add that the reservoir attachment isn't cemented, so that I can remove it and have a backpack as a reservoir instead (the point of using vinyl tubing at the bottom). That way the gun is way lighter and can be as short as 22 inches if I unscrew the nozzle as well.

Thanks for the feedback!
Armory: AS Hydroblitz (x2), MI FlashFlood, STE TripleShot, XP Backfire, XP 215, XP 105, XXP 175, Big Bottle BLaster(x2), SC Power Pak, SpeedLoader1000, SpeedLoader 1500, SpeedLoader Double-Cross 3000, CPS Splashzooka (x2), CPS 1200, CPS 1500,CPS 2100, CPS 2000 Mk2, CPS 1-3-5

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C-A_99
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Re: My CPH concept

Post by C-A_99 » Wed Jul 08, 2009 4:39 pm

Yeah, I noticed the reservoir area being slipped on and taped up. Good call there.

With that said, I'd like to suggest hose barbs or water balloon filler nozzles. (if you can find good ones; I've tried several WB fillers, but no barbs yet) My CPH has 2 LRT layers (total thickness is roughly 4mm), and with one of those nozzles, outranges my friend's 2000 by about 2ft. The drilled orfice of endcaps is not smooth, which degrades lamination rather significantly.

If you want to get serious with the trigger, perhaps a system of gears could be experimented with. The idea would be to have a longer trigger that requires less force to pull, as opposed to a shorter trigger that's more difficult. You'd also have to use a wood board or something to hold it together. Such a system may also be more difficult to tap shoot with.

Now for the questions. First, how does a 4-finger grip feel? It seems like it would be somewhat more difficult to grip the homemade with, but I've never worked with one. Second, how is the reservoir filled? Is there a small cap on the top of it? Also, it's a bit difficult to follow the design in some areas. I can't see how the PC case and reservoir is seperated. They seem to be by a part inside that I wouldn't recognize.

I'm also curious to how much PC ventillation is really needed for efficiency. It seems that anything better than the spherical CPS cases would work well. What I'd like to see is something with the Vindicator's concept, but with a check valve instead of a ventillating cap. (which aren't much good I must add; they always leave negative pressure in the reservoir for many guns) A check valve would slow things down a bit, but since they're large, they should provide plenty of ventillation, and also guarantee that the reservoir will not leak at all. (while a ventillated cap in stock blasters may leak if it's old) Perhaps building a check valve with a lower-pressure spring might be better to make for easier PC expansion and contraction.

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Silence
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Re: My CPH concept

Post by Silence » Wed Jul 08, 2009 8:14 pm

A longer torque arm solves the problem – no expensive or custom-made gears required. It sounds like the gun has a good trigger pull anyway, though. Remember that a 1/2" ball valve takes more energy to open than the valve in any commercial water gun, so it may not be possible to open it with a single-finger trigger and a short pull. You also need to double the amount of work because the spring needs to store enough energy to close the valve afterward.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Thu Jul 23, 2009 4:16 am

Ok to clear up some confusion about the design here is the picture I was talking about, finally :

Image

Pictured above is all the parts that can be detached from the current design.

The magic between the reservoir and the pressure chamber is just a 3" PVC endcap surrounded by a one inch long part cut out of a 3"ABS coupler. The PVC endcap fits perfectly within the abs coupler piece, and the coupler piece fits perfectly within the 4" drain pipe as well. So I just had to epoxy/cement everything inside and that's it, the reservoir is separated form the PC. (I apologize for not having a picture of this as I'm too lazy to disassemble it again :rolleyes: )

As for the reservoir, I still have to find a way to shut It's opening without blocking air to get in. I was thinking about another check valve but I thought that there should be another leak free and more simple solution... haven't found it yet.
Armory: AS Hydroblitz (x2), MI FlashFlood, STE TripleShot, XP Backfire, XP 215, XP 105, XXP 175, Big Bottle BLaster(x2), SC Power Pak, SpeedLoader1000, SpeedLoader 1500, SpeedLoader Double-Cross 3000, CPS Splashzooka (x2), CPS 1200, CPS 1500,CPS 2100, CPS 2000 Mk2, CPS 1-3-5

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Silence
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Re: My CPH concept

Post by Silence » Fri Jul 31, 2009 1:53 pm

That's a really useful picture; thanks for taking it. I'm noticing a large amount of empty space in the front of the big pipe, though; is there anything you can do about it? It's too bad the fittings take up so much space.

For an air inlet, a hole with fabric over it might do. If that doesn't work, drill a hole and tape a sheet of rubber behind it. I wanted to do something like that on the piston of a piston valve once; it's basically a very cheap, low-profile check valve. It won't seal very well with no pressure behind it, though. You might be able to solve that problem by using a surface that is convex from the inside and concave from the outside, and the stretch of rubber should hold it in place.

That's all speculative though. Hope you figure out a solution.

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