Homemade projects to begin

Build a homemade water gun or water balloon launcher and tell us about it.
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C-A_99
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Homemade projects

Post by C-A_99 » Tue Nov 21, 2006 12:32 am

I've decided the time is coming to start building guns since break is coming, and I can use that time to do this stuff, and also because it's too hard to find a good deal on ebay with guns like the 2500 or the 2000. I still have some things I haven't decided, such as the general thickness of the pipe, specific parts (particularly valves) to use, a layout, the pump, and whether to build a CPH or APH. (I'm thinking of a CPH right now) Actually, I'm not sure if I should build the blaster or a water balloon launcher first, though I'm rather aiming towards the blaster right now. (WBL's have little place in free-for-all games) I have no experience at all in building water guns and don't really know much about different parts, etc. (which dad is probably helping me with as well as with things like the cutting, gluing, and priming) I'll probably browse through Lowes sometime during break, maybe after I get some of my current guns repaired.
Last edited by C-A_99 on Sat Dec 16, 2006 10:45 pm, edited 1 time in total.

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Silence
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Post by Silence » Tue Nov 21, 2006 10:32 pm

Excellent...this could be a good "General Information" thread for homemades.

Now, as usual, I'm going to direct you to the standard APH article, by Ben of course. It definitely provides most of the information you'll need.

The PVC type you should use is Schedule 40. You can't really pump the gun up to a dangerous pressure...unless you use a 3/8" pump or something instead of 1/2", and such a small size usually isn't available.

For a pump, used the type in the article linked to at the bottom of the APH article. Don't buy tiny circular O-rings, as you'll be kicking yourself later on--this is so much easier!

A CPH is probably better--cheap, powerful, CPS--and I would suggest against an APH. Sure, the dropoff can be countered using tap/pump, but such a large PC with a large nozzle is going to require a lot of pumping, and you can lose power if you can't pump in time.

This is going to require ordering online, and I think you live in California--so McMaster-Carr will probably take a week or so to get the parts there. There might be another store or online reseller. Ben should know... ;)

I don't know too many variations besides basic ones to the conventional CPH layout. That calls for the nozzle, ball valve, tee, and PC all in a line--with the PC opening facing the front. The tee points down, and the tubing goes around the PC cover tube to the back of the pump. There are check valves on top of and behind the pump, and you'll probably use a backpack. If you've got a neat design in mind you could draw a picture or something.

Hope all goes well!

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Post by C-A_99 » Wed Nov 22, 2006 3:31 am

I live in Michigan... lo.l (and I saw the APH article several times) What I think I'll do is create a layout in PVC designer, creating both top views and side views since I plan on using 2 PC's. One thing is, do I just cover up the PC's with regular thick PVC? (like the one used for the PC's on the APH) Also, I need suggestions on valves, I kind of forgot the names, but I think it was called the metal ball valve. (whatever it was, it was one that nearly allowed for tap shooting and better than the other one)

On a side note, I'd like to have a PRV, more important for the water balloon launcher, simply because I want to limit the pressure the water balloon launcher is launched at. The battlefield is very small and such far distances are unecessary, and aiming up in the air just doesn't seem practical if you want to hit targets, and it'd be better to aim a bit more directly. (I'm going to
try to set up something to keep the water balloon launcher users in a certain area, somewhat isolated from the rest of the field) On a second thought, a lot of my friends want to have free-for-alls instead, which is why I opt to make the CPH first.

Now for the parts, are certain parts only availabe for order online? (like the LRT and the metal ball valve)

Edit: Here's one I made with PVC designer, just to get an idea at least.

From Top.

Image

From Side.

Image

Edit: Why does it filter "l.ol"? Completely messed up my post without me noticing it. (and on every other forum people use that, doesn't make anything look better taken out)
Last edited by C-A_99 on Wed Nov 22, 2006 5:50 pm, edited 1 time in total.

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Silence
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Post by Silence » Wed Nov 22, 2006 4:29 pm

Don't use two PCs for a CPH. The LRT could be of different strength, and then one bladder will fill before the other one. Also, that prevents linear flow (a straight path for the water from the PC and through the nozzle).

Metal ball valves are easier to open and open more quickly than PVC ball valves simply because they come fitted with long opening levers. You can use PVC and clamp it using a screw onto a PVC ball valve to get the same effect. You should also grease each one; don't use petroleum, which will degrade the rubber seal.

For a water balloon launcher, the footpump usually used has a pressure gauge on it. CPHs have constant pressure/force, so you don't need to worry about that. And even with APHs, the last 25% of the pumps get progressively harder but the distance pretty much stays the same.

You can get metal ball valves at Lowes. But LRT has to be ordered online. You should get your items within days; it only takes hours to get to people on the East Coast.

Looking at the top view, you can see how you don't get laminar flow with multiple PCs. And for the side view, the connector from the back of the pump to the tee in front of the PC should go underneath.

LRT expands to 850% of its inner diameter (ID), and it increases in length to about 300%. You use 4" PVC for the case, but since it holds no pressure, and rating is fine--my Lowes only carries pressure rated tubing up to 2". Cellular core/non-pressure rated is okay for the casing.

Go to their LRT page and you'll see all the sizes. For each layer, the ID should be larger than the OD of the layer inside so it can slide on. Use bicycle inner tubing on top for even more power if you wish. Ben can probably provide the numbers of the best products.

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Post by C-A_99 » Wed Nov 22, 2006 6:07 pm

What do you mean by the different strengths and one bladder expanding before another?

Oh yeah, just wondering, what if I made the PC case airtight for more pressure? Probably not a good idea, but I'm just wondering why.

I also need a link to that place where you order LRT. (some McMaster place, I forgot the name) I saw it sometime earlier on the forums but forgot where it was. (though I'll look again later) Doesn't look like the gun has a very good grip so far so I'll probably have to completely rely on a strap.

Image

I might make the pump partly tracked, slightly attached onto the portion above it.

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Post by Drenchenator » Wed Nov 22, 2006 9:59 pm

Oh yeah, just wondering, what if I made the PC case airtight for more pressure? Probably not a good idea, but I'm just wondering why.
For some reason, this is brought up often. First of all, it would put the bladder under extra stress. If it breaks from this stress, it could not be replaced. Second of all, it defeats the purpose of CPS: constant pressure. The extra pressurization would make the pressure less constant. Last but not least, the use of pressure rated pipe for the bladder casing would seriously raise the price. 3" or 4" cellular core would be fine. I have also considered replacing the casing in my CPS homemade with 4" drainage pipe because it would be even cheaper, lighter, and larger.

Other than that, the design so far looks fine. One chamber should be sufficient; two would be unnecessary. The main reasons are that two would ruin laminar flow and that one already has a high capacity. My CPS homemade with one small bladder fits 1.8L easily.
The Drenchenator, also known as Lt. Col. Drench.

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Silence
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Post by Silence » Wed Nov 22, 2006 11:43 pm

The rubber thins and weakens when it gets stretched. The weakening can be uneven, so one bladder might become slightly weaker than the other. If that is the case, then it will stretch until it reaches its maximum instead of both stretching equally.

Drenchenator got to the other problem. I never explicitly said that the volume would be huge; but if you consider the expansion percentages, a 3/8" ID by 6" length section or whatever will grow to humongous proportions. You don't need any more.

You order the parts from McMaster-Carr...I said so three posts above yours. The website is http://www.mcmaster.com. Their system doesn't allow hyperlinking to the URLs of individual products; you have to use product numbers, which Ben should know. I'm sure I could find them without too much trouble, but I'm feeling lazy at the moment--just drove an hour to Richmond to shop for god knows how long.

At any rate, I'd suggest you wait for Ben to post before you continue. Then again, Drenchenator probably knows a lot too. I'd highly suggest checking out his CPH thread--get job on the gun!

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Post by C-A_99 » Fri Nov 24, 2006 5:37 pm

I don't think a PC case is necessary now, can't I go without one? And to confirm this, I am indeed using a backpack. I believe I need to adjust the diameter of what I used, using 1/2" for around the pump area, perhaps it will lower the pump resistance and make it slightly easier to pump. (while requiring more pumps) I still need to make some final decisions, mostly dealing with the pump. I will probably get 3ft of vinyl tubing for the backpack though I'm not sure how to make the connections between the trashbag in the backpack and between the tubing and the blaster. I am also slightly worried about the ease and comfort of handling the gun. How much space should I allow for the LRT to expand? I'm thinking of around 4" right now. I still need to know what diameters of LRT to use. Also, I don't know how to build nozzle selectors.

Image

Edited in paint of course.

Edit: Progress is currently being delayed by other random stuff, I guess I'll have to just look for time later on, didn't even get the PVC yet, but I want to know as much as possible about what I'm going to do so I don't buy unecessary parts, or not buy enough since I don't have the time to make so many trips around.
Last edited by C-A_99 on Thu Nov 30, 2006 10:58 pm, edited 1 time in total.

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Post by Silence » Fri Nov 24, 2006 7:28 pm

A case is essential to verify that the bladder won't get scratched--as those scratches can develop into tears. It also protects you in case the bladder explodes due to overpumping. And finally, it stops the empty bladder from flopping around and makes the gun look better.

Almost all homemades use 1/2" pumps--the exceptions are PPPs and low-powered but fast-pressurizing homemades, not recommended but perhaps decent for CQC.

The hose connections are done with hose barbs--basically PVC adapters--and Jubilee clips, or round clamps that hold the hose onto the barbs. You don't need to cement them to the gun, as they hold no pressure. You will need epoxy to attach one to the backpack reservoir.

Give 4" of diameter for the expansion (2" in each direction), maybe a bit more if you choose to use PVC or CPVC as a case later on. I don't know the diameters off the top of my head, but it might be something like 3/8" ID and 3/4" OD, inside 7/8" ID and 5/4" OD. Something like that--you should be able to squeeze the bottom layer on a 1/2" hose barb, and the outer layer should slide right on.

Read the nozzle selector modification article at the main site to see how the nozzle selector works.

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Post by C-A_99 » Sun Dec 03, 2006 1:03 am

*phew... Just got back from Lowe's. I picked up all the basic joints and stuff, but I still need to get some 4" for the PC case. Also, I'm a bit unclear on how the metal ball valve connects to PVC, so I currently just got a PVC valve, can I use PVC valves for a water balloon launcher? (I'm going for an inline launcher similar to the Douchenator, though it might come out a small bit different.)

I also need to find parts to attach to the LRT and get it connected to the rest of the gun while creating an end for it. In addition, I seem to be having trouble creating a seal. I'm currently looking at drench's CPH thread and the articles around the site. The aluminum rod was rather expensive. (the metal ball valves probably are too) I got 1/2" OD for the rod, which I believe is incorrect, though it still fits into the 1/2" PVC well. I'm not sure about the O-rings though. I also overheard that there are better seals than O-rings and electrical tape. I also got 1/2" OD, 3/8" ID vinyl tubing for the backpack, and some piece with a 1/2" male end to go into a 1/2" female adapter, which then connects to the 1/2" check valve.

Edit: Nevermind about the PVC valve for the WBL, I'm going to use a solenoid valve.
Last edited by C-A_99 on Sun Dec 03, 2006 3:31 am, edited 1 time in total.

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Post by Silence » Sun Dec 03, 2006 3:27 am

Somebody needs to educate me on what PVC size or fitting can be glued to metal ball valve--I'm assuming it's Schedule 80 PVC, as the others don't fit, but I don't remember. However, the threaded versions (that don't have the smooth sockets intended to be cemented) can fit onto PVC threads.

A PVC ball valve is okay, if you really have to use it, just make sure you add a torque arm to it. Otherwise it would open slowly, and you'd have a launcher as bad as the Mythbusters' pneumatic ones. But why do you want to use it for a WBL, not a CPH? If anything, it's the WBL that needs a fast valve, and PVC is fine for a CPH.

Use a tubing barb fitting/pipe nipple and push the LRT onto it, then use a thread adapter to screw that onto the homemade--or just don't use threads and glue, as no pressure is held there. Use a Jubilee clip on top of the barb and the tubing to hold the tubing on. Ask somebody at Lowes if you don't know what something is or where it is. ;)

It sounds like you got the right hose barb and the right tubing (it's large enough for good flow; the barbs have smaller IDs than the tubing and restrict flow) for the backpack. Now just get the appropriately sized barb for the LRT.

You'll be much happier if you get a 3/8" pump rod. Trust me. A 1/2" rod will work with a very small O-ring, but I don't know the sizes as it was one that was just lying around. It's non-stretched dimensions are much smaller than that of the rod. A different size than the one I found won't work, and you'll still spend a ton of time trying to perfect it. I'd rather have gotten a 3/8" rod. You'll need some tape underneath and on the side, and I went through about half a roll of it. :p

It doesn't really matter what type of material you get, aluminum or wood; and steel is okay too, just a bit heavier. People say wood allows you to cut underneath if the O-ring is too big, but I wouldn't trust myself to create a clean groove. Better to get something of these dimensions: 3/8" rod (any material), O-ring with 3/8" ID and 5/8" OD. The OD isn't too big because Schedule 40 PVC's ID is slightly larger than what it says; that's why the 1/2" rod fits. This O-ring will also have flat side, which is great because it can't roll over or under the tape, which was another reason I used so much tape on my APH.

There is no seal better than an O-ring. They're used in everything, I can't think of any product that opts not to use one but still has good efficiency. Some people used to use duct tape, and I'll grant that it is a good idea for the sides as it won't peel off, but I find that it's difficult to cut.

You might be thinking of Drenchenator's method of holding the O-ring in place. Get CPVC with an ID the size of the rod's OD (CPVC isn't larger than its name, and it's very cheap but can't hold pressure), cut two thin pieces out, and glue those onto the rod, on each side of the O-ring. Permanent seal.

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Post by DX » Sun Dec 03, 2006 3:29 pm

You can't glue PVC to a metal valve. At least I don't think you can. I've always bought threaded valves for the interchangable options. I've also been experimenting with using a short strip of FBR rather than O-rings as pump seals. I hate O-rings because they can get stiff after not being used in a while. FBR, however, slides easily no matter what. I wanted to try this using Drenchenator's method of holding it in place, but of course I now have no time for anything.
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Post by Drenchenator » Sun Dec 03, 2006 7:29 pm

I'm a bit unclear on how the metal ball valve connects to PVC
Every metal fitting is threaded. Both PVC and metal fitting use a common thread size for each size of pipe called NPT (national pipe thread), so they can be attached to each other easily. Valves tend to be female-threaded, so all that you need to connect them to PVC is a PVC male adapter (below) and teflon tape for a good seal.

Image
I also need to find parts to attach to the LRT and get it connected to the rest of the gun while creating an end for it.
All that you need is a hose barb fitting. These a male threaded, so you would also need a female threaded adapter to connect this to the PVC. The other end can be plugged with a bolt. Use hose clamps to ensure a good seal.
I seem to be having trouble creating a seal. I'm currently looking at drench's CPH thread and the articles around the site. The aluminum rod was rather expensive. (the metal ball valves probably are too) I got 1/2" OD for the rod, which I believe is incorrect, though it still fits into the 1/2" PVC well. I'm not sure about the O-rings though. I also overheard that there are better seals than O-rings and electrical tape.
O-rings provide adequate seals. If you have trouble, use multiple. If you are interested in how I built my pumps, view this post which describes how to build it.
The Drenchenator, also known as Lt. Col. Drench.

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Post by Silence » Sun Dec 03, 2006 9:48 pm

DX: Would the FBR you're referring to be Foam Backer Rod? if so, then I don't know if its seal would be tight enough. But it would be nice to know. Also, I'm wondering what is used for those commercial soakers with non-O-ring seals.

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Post by C-A_99 » Sat Dec 16, 2006 10:43 pm

Made another trip, this time to 2 different Home Depots. All I got was a 3/8" wooden dowel and a quick connect/disconnect adapter, didn't even get the proper O-rings I needed, and tried to get other valves for the water balloon launcher. I (and the people around) don't really know what the solenoid valve is, heard it was operated electronically too. I think it'd be easier to just use a PVC or metal ball valve, but I've heard they take too long to release the sudden burst of air. Could lubricating and adding a torque arm to the PVC ball valve bring it to an acceptable level of releasing the air?

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