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Plans for the future

Posted: Fri Mar 17, 2006 4:10 pm
by joannaardway
At the start of next month, I will be buying a last few super soakers from various sources, and then I plan to move almost entirely to homemades (unless something good comes along)

I have no experience with homemades, but as far as I understand, with care, there should be no problems incurred - however the lack of experience will probably show up in some of my homemade plans.
I have no idea about the limits of homemades, so if I aim too high, please tell me.
On the other hand - I have enough experience of water guns and modding that I shouldn't find anything too hard. The biggest problem will probably be the availability of parts.

By the end of next month, I'll probably have my armoury into double figures and it will cover everything from small pistols and XP "assualt rifles" to large CPS weapons, so I'm looking for homemades that are completely out of the box relative to this.

My first plan was to build the Cerberus water balloon launcher I have been detailing in "Water balloon topic" - it's completely off the wall compared to anything I'll have from Larami/Hasbro, so it's far enough from it to be my first choice for a build.

After the Cerberus, I had plans for (but not necessarily in this order)

- An APH based on the one on this site.

However I think I'll be building it with 4 PCs that can be turned on and off independently, to allow it to fulfil various different roles.

- A massive CPH loosely based on the Splashzooka.

And I mean massive - I'm planning to link three 3 litre CPS PC chambers together for a massive 9l capacity. It'll be dual fillable - both hose connection and pump (for if a hose isn't available) which might be able to feed from an optional backpack.

Ok, it'll take a long time to fill, or around 200 pumps with a large capacity pump, but on rough estimates, it will have around:
  • 15 seconds of 20x fire
  • 30 seconds of 10x fire
  • a minute of fire time on 5x
  • 2 & a half minutes on 2x
And imagine a riot blast - even at an optimistic 50x, I'll still have 6 seconds of shottime available.
So with PCs that big, there should be no shottime issues.

I'm thinking 3 PCs because one 4' to 5' long PC is impractical and probably far too big - three 15" to 18" long 4" diameter PCs can be mounted alongside each other for a 24"-30" long weapon at maximum.

Obviously, air pressure isn't that practical here, so this needs to be CPS.

This is the more optimistic design of the three homemade plans I have (including the Cerberus).
I think it's possible, but I'd love feedback. If it's possible, I don't have too much trouble with impracticality of the build.
Anyway, after building the Cerberus, the others should be quite easy.

So what do people think of my plans? For now it's going to be just the water balloon launcher and the two homemades, but I might add "The Ultimate water gun" to my build list after I've finished a couple.

Posted: Fri Mar 17, 2006 8:43 pm
by m15399
Ben says multiple CPS chambers don't work well. That sounds right (one would fill faster than the others and pop) and the only way to counter this would be to have good PC casing.

I just had an idea. What about a air/CPS hybrid? The CPS chamber would be connected to an external air pressure tank. Is that crazy or what? I wonder how it would work...

Posted: Fri Mar 17, 2006 9:00 pm
by joannaardway
But, with a good casing, if one chamber fills or empties first (as it will - it's a basic law of physics) it's not a problem, right? How does the SC power pak work - doesn't this have multiple chambers? Do these move seperately?

I thought that a 4 foot PC (and it would result in a 5 foot long weapon) would be impractical, or impossible, so I posed the 3 tank idea instead, because 15" PC chambers sound possible (the splashzooka's PC is longer is it not?) and a 2 foot long weapon would be managable and actually quite convient.

I have no problem with making a decent casing for it - I was planning on making them anyway.

Posted: Fri Mar 17, 2006 10:12 pm
by SSCBen
Sound great. My very old single chamber "Leftovers" water gun was very much like you described. Despite what most people think, I still maintain to this day that shot time is the most valuable statistic. The 2 minutes 21 second shot time was great, and I was only using one chamber! Imagine multiple chambers! Nothing could match this water gun for one reason - all of my opponent will have to recharge earlier than I will, so I can easily attack during that time.

Multiple chambers are possible, as the SC Power Pak demonstrates. The problem however is even filling. In a rubber CPS water gun system, the chamber that is easiest to fill will be the only one that will fill. I have done a lot of little experiments with this that exhausted my supply of LRT. Even given a chamber that was used only once against a chamber that was never used, the one that was used once already thinned enough to cause the other chamber to not fill at all. I know the newer chamber did not fill because of one thing - I purposely caused the thinner one to pop as part of my experiment.

Multiple chambers are possible given that the rubber thins evenly. You will have to replace the rubber fairly often if you can not manage to make a system that does not ensure the rubber thins evenly (which isn't very hard to do really). I made a small test set up with two new chambers, and both did expand evenly. I mainly did not recommend using multiple chambers before because people intended to collosus them, and in my experience even a system composed of two similarly collusused tubes will have a problem where one will fill while the other does not.

Also, when using multiple chambers, all chambers will expand at the same rate. Some people seem to think that I mean one chamber will fill while the others remain empty, eventually letting the others fill in sequence. That is a common misconception. The only time when one chamber will fill at a time is when one chamber is thinner than the others.

As for what you have described in your water gun joanna, I think you are being quite conservative, especially in the PC length. I used a single 12 inch long piece and got 3 - 4 liters of capacity (if I remember correctly). I would recommend using four 12 inch long tubes in a backpack setting. I know this probably isn't what you might have expected, but this system will give you 12 liters or more depending on how you construct.

Given how easily you've picked up the concepts and modified your water guns, I don't suspect that you'll have any trouble. Just remember one thing - ask or experiment if you have questions.

I was working on a little more to say, but I've lost most of it now that I got around to posting again. Let us know if you have any other questions or ideas because these threads can really be productive! ;)
I just had an idea. What about a air/CPS hybrid? The CPS chamber would be connected to an external air pressure tank. Is that crazy or what? I wonder how it would work...
There are at least 10 threads on this very idea (I'll give you links if you want them). That is an extremely common idea. I don't recommend it because (1) the system is no longer CPS (2) it would be hard to construct and replace the CPS chamber later and (3) you could make a more powerful constant air pressure system easier. The CPS chamber also likely could not take outside pressure very well. You don't squeeze them, so why would you put even more pressure more evenly over them?

Posted: Sat Mar 18, 2006 12:03 am
by m15399
I think you're not getting what I'm saying. I've seen threads about pressurizing the outside of the chamber (I think that's what you thought I meant). I mean like the end of the CPS tube is connected to a seperate air pressure PC. It is probably a bad idea, but it popped into my head.

Posted: Sat Mar 18, 2006 12:38 am
by SSCBen
That idea literally would have no effect on performance and only be unnecessary space. I think that you are forgetting that any pressure created in the system would expand because the rubber allows for expansion. ;)

Posted: Sat Mar 18, 2006 10:13 am
by joannaardway
Nonetheless, if a CPS chamber fills first and hits the walls of the casing, wouldn't that in turn cause the next one to fill? (as no more can go into that chamber)

I did think of a power pak like setup. And it would be easier to carry, if built sensibly. I imagine I will still use 3 PC chambers though. 9 litres is quite enough - especially if I need to run (not that I'm that fast anyway).

I will be building the CPH with a pump, so I presume that I can use the same hose for feed to and from the backpack.
I can see no problems with this, assuming that I won't be lucky enough to be able to pump/fill and fire at the same time.
But I could build with two hoses - one for pumping, the other for firing.

However the hose used will affect the maximum output of the gun will it not? (assuming a sensible diameter) I had amusing plans for a 6 second riot blast. 2 to 2 1/2 pints of water a second would have been amusing.

Although for that matter, how possible would it be to use multiple feed hoses to allow for this (or close to it)?

I'm assuming the APH and water balloon launcher should be no problem. The APH isn't too radical.

The Cerberus water balloon launcher is just a modification on standard tech using more electronics - the construction won't be a problem, most of the trouble will be with timing the solenoid to get two shots per tank (even if I have to shut the valve off a fraction early, I can afford to lose a small fraction of the muzzle velocity [there will still be pressure in the barrel remember]).

The tanks will be in roughly a 2:1 C/B ratio, and with reasonable timing, I've used the spudtech modelling tool to work out that the dregs will be enough to fire with.

The solenoid valve may need modification to make it entirely possible, but six shots before a recharge, with a breech load, a scope and rifling (if it can be done - I need to work out it's twist rate first though) should set the Cerberus at the pinnacle of water balloon launcher technology - if it works.

Posted: Sat Mar 18, 2006 2:21 pm
by SSCBen
Nonetheless, if a CPS chamber fills first and hits the walls of the casing, wouldn't that in turn cause the next one to fill? (as no more can go into that chamber)
I did not test this, so I am unsure. It could go either way based upon what I have seen. Initially, the other chambers would fill as well from my thinking. However, if the one chamber is too thin and thinning because it is being used in that fashion, I would tend to believe that after time the chamber will eventually be so weak that filling the other chambers would be harder than popping one chamber, so what obviously will happen is that one chamber will pop.

Simply try to avoid that situation. All chambers should move simultaneously to prevent problems.
However the hose used will affect the maximum output of the gun will it not? (assuming a sensible diameter) I had amusing plans for a 6 second riot blast. 2 to 2 1/2 pints of water a second would have been amusing.

Although for that matter, how possible would it be to use multiple feed hoses to allow for this (or close to it)?
A single hose's force is higher than the 1/4" rubber tubing's is, at least in my area. I think you'd have trouble getting a 6 second riot blast from a 9L+ setup, so you might want to rethink that. Had the system been collosused with many layers, you might be able to get a good 20 - 30X stream from the nozzle, but that would also remove the important and convenient QFD ability.

As for multiple hoses powering a single water gun, some have proposed that before, but no one has tried it yet. I figure it would give you twice as much output and therefore twice as much force, so it should in theory allow you to fill a thicker chamber. Give it a try.

Some others in the past (such as myself and a few others) have also proposed a QFD with a pressure chamber. The idea is that the hose fills a larger pressure chamber, pressurizing it. Afterwards, either a pump or air compressor increases the pressure to quickly fill more powerful systems. The air compressor and QFD combination sounds the best to me.

Posted: Sun Mar 19, 2006 9:23 am
by joannaardway
When I said feed hoses I meant from the backpack to the gun. What would the limits of a single feed hose from the backpack to the gun be?

Presumably, more feed hoses = more internal diameter.

For filling, I believe that a single hose should be sufficent.

As a crazy idea, what about 3 PCs in a backpack, with an extra one in the gun? I don't know if I'll do it, but it would enhance capacity. (And it would allow the weapon to be used without a backpack)

Posted: Sun Mar 19, 2006 4:50 pm
by m15399
If you only want 9L, then you really don't need 3 CPS chambers. You could do it just as easily in 2. If you want MORE than 9L, then by all means, go with three. It looks like Ben's holds about 4L.

Posted: Sun Mar 19, 2006 6:14 pm
by joannaardway
Three PCs are likely to be needed, or at least is my preference.

What follows is my logic for this.

9l divided by 3 PCs = 3l per PC.

Assuming a 4" diameter PVC casing:

The radius with be 5cm

5^2*pi = 78.5cm^2

3000cm^3/78.5cm^2 = each chamber is 38cm/15" long.

This is about the size I feel that is reasonable (and about the length of the PCs on the SC power pak.)

I am still unsure of whether it will be a backpack or handheld soaker. I'll consider this further. The backpack will cost more, but will be more convient.

What are the thoughts on 3 pcs in the backpack + a PC in the gun? I think that 4 PCs in the backpack might well be excessive, so for serious capacity, it would be a good way to go.

Posted: Sun Mar 19, 2006 8:07 pm
by m15399
To me, 15" isn't very long in a backpack. Oh well.

How would you have the PC in the gun connected? Just have another tube leading to the nozzle with the rest of them?

Posted: Sun Mar 19, 2006 10:43 pm
by joannaardway
15" may not be that long, but I might be fitting it inside a standard backpack along with supplies, and it needs to be more compact for that.

The extra PC will probably be fitted almost as you described (if it makes the final cut) - but some how fitted so that I can disconnect the backpack, and use it as a stand-alone piece for mobility. 4 PCs is appealing, but it's too much to put in a backpack in my opinion.

Posted: Sun Mar 19, 2006 11:19 pm
by SSCBen
You should redo your math. The radius is definitely going to be less than 5 cm. The tubing does not expand indefinitely if you're under that impression. You will not need to put the tubing in anything really, in fact it would be best for capacity to put the tubing into a casing larger than the tubing itself. The tubing I had was larger than 3 inches in diameter (3.74 cm radius) when full (it did not fit loosely into 3 inch ID pipe), and I am assuming that you will be ordering something similar.
As a crazy idea, what about 3 PCs in a backpack, with an extra one in the gun? I don't know if I'll do it, but it would enhance capacity. (And it would allow the weapon to be used without a backpack)
I personally don't think that there will be too much of an advantage to having an extra PC in the gun part. If you really wanted an extra few liters of water, that sounds like a great idea, but I think we've got plenty of capacity already. 9 liters is a lot, nearly weighing 20 pounds or 9 kg! Of course, with the right backpack setup (i.e. a frame backpack), most people could handle more weight, but I think we've got plenty as far as capacity is concerned.

Go ahead and try the extra PC in the gun idea. It might turn out to be really convenient for all I know. ;)

Posted: Mon Mar 20, 2006 3:14 pm
by joannaardway
I have no experience of latex tubes, so bear with me.

If the latex tubes only expand to around 3" inches in diameter, then maybe I should rig five 18" long 3" tubes togheter for around 10L (two stacked on top of three). It wouldn't be too inconvient, and would probably cut the need for the gun based PC.

However, perhaps the gun based PC could be a reserve - if the backpack runs out, then by use of a ball valve, the extra PC could be turned on as an emergency supply.