My CPH concept

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

Post by SSCBen » Wed Aug 06, 2008 9:32 pm

The length shouldn't affect performance or durability much. It's more of a question of how much capacity you want or space you want to use. For that size, yes, 8 inches should be great.

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CROC
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Re: My CPH concept

Post by CROC » Thu Aug 07, 2008 12:21 am

If you go with 8", cut a circle the same size as the plug on the LRT so that when it expands, it has space for the end of it to go, allowing for further expansion. Would that not work?
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SSCBen
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Re: My CPH concept

Post by SSCBen » Thu Aug 07, 2008 11:45 pm

That'd get an extra inch or two, yes. The location of the hole would depend on the angle the gun is held at though, so it probably wouldn't work very reliably unless you cut a slit to allow for a range of angles.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Fri Aug 08, 2008 11:21 pm

I've tested the gun with LRT today. The results are less successful than what I was expecting....

I started by using only the smaller LRT just to se how much power it has. It's kind of powerful, but not impressive. Actually, my lastest homemade spherical bladder has more kick and power than this.

So I tried to put the lager LRT over it using larger hose clamps. It has been well performing. Great shot time and between 40-50 feet of range with a nozzle on par with the CPS 2000. But the smaller LRT didn't held a long time. After a few shots It bursted completely inside the larger tubing, resulting in water stuck between the two layers of rubber tubing. Letting out the remaining water has been a bit tricky, because pulling the trigger wasn't doing anything and unscrewing the endcap at the end of the bladder didn't worked either. So I had to loose one of the tubing clamps. Fortunately I didn't got "too" wet doing this. :p

But, wow, the result isn't pretty:

Image

I'm not sure of what to do now, as my LRT supply is limited. I once had the idea of a simple design modification that could be done using my spherical bladder, wich would allow an onboard reservoir of near 4 liters and a PC capacity of 900mL. But I thought that LRT was better....

Any suggestions?
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

Killer 7
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Re: My CPH concept

Post by Killer 7 » Fri Aug 08, 2008 11:48 pm

I had a similar problem with one of my guns. The problem was that the LRT could expand too much, and that caused it to wear out very quickly, like after two shots. So you could try making the expansion vessel smaller, or use LRT with a larger ID. I used LRT with a larger ID and have not had to change the LRT in the gun for over 7 months. any way I hope this helps.

Edit: I just read that you were using 4" ABS, if you can use three inch it would probably help alot. I know that it will kill the capacity, but having a working gun with less capacity, is better than having a gun that requires expensive repair every few shots.
Last edited by Killer 7 on Fri Aug 08, 2008 11:55 pm, edited 1 time in total.

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SSCBen
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Re: My CPH concept

Post by SSCBen » Sat Aug 09, 2008 12:42 am

That's weird because the smaller tubes I sent you were unused. The larger one had a few uses but not many.

I bet this has something to do with the clamping the larger one onto the smaller one. Killer 7 does that and you said you do that. I haven't tried that yet, and I've never experienced this problem, so I'm guessing it has something to do with that method. Reducing the expansion should solve the problem.

I'm going to take a guess as to why it happened. There is some air space between the two tubes and perhaps the pressure differential between them caused some problems. If you eliminated the air somehow it probably wouldn't break from my thinking.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Thu Aug 14, 2008 5:11 am

Ben wrote:I'm going to take a guess as to why it happened. There is some air space between the two tubes and perhaps the pressure differential between them caused some problems. If you eliminated the air somehow it probably wouldn't break from my thinking.
I guess youre right, clamping the larger tubing over the smaller one should be avoided then. But the only reason why I've done that is because your method described in the superCPS guide didn't worked very well: the smaller tube was expanding out of the larger one after a few pumps. Maybe I was doing it wrong though.

Anyway I thought I'd detail the design modification idea I mentioned in my last post :

Image
The only predictable problem I see would be the weight when full, which would be very heavy. But the overall capacity and power would be good I think. As my last spherical bladder made of ballons performs much better than the first one.
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

aEx155
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Re: My CPH concept

Post by aEx155 » Thu Aug 14, 2008 4:25 pm

JLspacemarine wrote:The only predictable problem I see would be the weight when full, which would be very heavy. But the overall capacity and power would be good I think. As my last spherical bladder made of balloons performs much better than the first one.
I did a bit of math, and according to one site, if the water you're using is around 70 degrees Fahrenheit, 4 liters should weigh around 9 pounds. I think that shouldn't be too much to handle.

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cantab
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Re: My CPH concept

Post by cantab » Thu Aug 14, 2008 4:44 pm

The temperature makes hardly any difference, at least if the water is liquid at atmospheric pressure. (And if it's not then you've got bigger problems than the weight of the gun!)

4 l of water weighs 4 kilos. Hooray for metric!
The weight won't be an issue, unless it's heavy empty. Empty weight should ideally be below 2 kilos I reckon.
Balance is more important. I think it'll be a bit back heavy. You can rectify that by bringing the handle further back, but that might cause trouble with your trigger.

Also, I'd avoid having that vinyl tube running across outside the gun like you've shown. It will be liable to get broken. Either use rigid pipe, or route the tube differently so it's always against something more solid.
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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Silence
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Re: My CPH concept

Post by Silence » Thu Aug 14, 2008 6:07 pm

It's nice to see a good use for spherical bladders! They come in handy in cases like this, where pretty much any length of tubing would stretch too much.

I agree you may find the water gun back heavy when full (but comfortable when the reservoir is empty). But it doesn't look like you can move the grip back too much since you've already built the front assembly. The trigger wire shouldn't get in the way since you can just extend the sliding piece that the trigger is connected to.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Thu Aug 14, 2008 8:59 pm

cantab wrote:The weight won't be an issue, unless it's heavy empty. Empty weight should ideally be below 2 kilos I reckon.
Right now it weighs 5 pounds empty, and that's without the ABS fittings that I plan to add. That's why I thought it would be very heavy when filled with water. The balance won't be a problem though, as the gun is already front heavy when empty.
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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cantab
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Re: My CPH concept

Post by cantab » Thu Aug 14, 2008 9:58 pm

That is a touch on the heavy side, but not extreme.
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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SSCBen
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Re: My CPH concept

Post by SSCBen » Mon Aug 18, 2008 6:27 pm

How's the design modification going? I was interested in it but never seem to have made a post about it.

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JLspacemarine
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Re: My CPH concept

Post by JLspacemarine » Fri Jul 03, 2009 6:52 am

Hi everyone!

Sorry for the late update but, good news, my homemade is almost completed. The result is pretty much what I was expecting.

Major changes:
-The trigger is now pulled by all four fingers, as the previous hook type trigger was too hard to pull with only one finger.
-Most of the gun is now painted black
-The pump handle is now vertical instead of horizontal
-Note that all grips are improved with bike tubing
-The ball valve and its mechanism has now it's own casing held by the laminator. (ABS test cap over a 4" PVC sleeve)
Image
Image
Image
Here are some stats:

Length: Between 22" and 32" (depending on what nozzle and reservoir is used)
weight empty: 7 pounds
weight full : heavy! :eek: (btw, it needs a shoulder strap)
Pressure chamber type: Spherical (75 9" helium quality ballons)
PC capacity : 1200 mL
Reservoir Type: Onboard (can be detached and replaced by a backpack)
Reservoir capacity: 3600 mL

*Range and output to be measured and posted soon, as well as a picture of the gun unassembled*
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 03, 2009 7:51 am

Yeesh, splash some color on that thing! It looks a little *too* professional. Anyway, on a more serious note, after re-reading the thread, I'm glad you managed to pull everything together after all the PC problems.

I suspect Drenchenator used a four-finger trigger for the same reason: it would've been too difficult to pull otherwise. How many inches/centimeters back do you have to move it? Judging from the ball valve pictures from earlier in the thread, it doesn't look too long.

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? Also, how many options do you have for the reservoir's length?

Anyway, this is impressive as usual, and I hope to see those pictures and stats up soon.

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