I think I need help: )

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
keep_it_real
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No, not really.

It's a good beginner cannon but that's about it. I think that 3 way valve is just for hoses so the pressure rating probably isn't that good.
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Counterstriker
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Ok thanks man! I am a beginner so i will make it : ) I will post videos as soon as possible!!
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jimmy101
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1. Don't bother with using the schrader valve recovered from an old bicycle tire.

Any decent automotive tire store, and most auto parts stores, and some hardware stores, will have metal shrader valves. (Auto tire stores really should replace the schrader valve, AKA tire stem, every time they replace a tire.) They are cheap, rubber ones for a buck or so, high quality threaded metal ones for less than $5. (You can also check near the compressors at your local hardware store.)

2. Don't glue the valve into the endcap. It is too exposed there and will get banged up. Put it in the side of the gun, preferably at a point where you have a fitting and pipe so you have a double thickness of PVC.

3. Do not use "cell core" or any other non-pressure rated pipe. The pipe should list a pressure limit on it somewhere. It really doesn't matter what else it says on the pipe, only that it actually lists a suitable pressure rating. The limit should be significantly above what you think your max pressure will be. (A 200 PSI rating is usually a good bet.)

4. For a plastic gun the only glue you should use on the fittings that will be pressurized is PVC cement. All joints should be cleaned/primed before gluing (read the sticky on glueing PVC). The only exception would be for the schrader valve where you can use soemthing like JB Weld or expoxy. If you get the right type of schrader then it wont need any glue.
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iknowmy3tables
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that gun kinda sucks for a how to gun. there are plain old one way valves for garden hoses its a crappy valve for firing. the easiest way to attach bottles to pipe is gluing 1/2" pvc in it the opening. all soda bottles (but not 3 liter bottles) have the same threads so use a 2 liter they have mor volume for more power. heres a even more simple gun: 2liter--1/2"pvc----1/2"elbow w schrader/tire valve--1/2" elbow--1/2" pvc ball valve--1/2"barrel
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fastcannonman
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i have one of thoes gardon hose faulvs. my dad dident use it for a while, so i used it for a cannon. man that was a wast of 20 bucks :(
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Counterstriker
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I love being a noob : ) Well.. I am going to Home Depot tommorow and i wanna make sure the have everything I need. Do they have the bycyle valves...(the true name escapes me) at home depot? I just to make one trip and not forget anything.
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A-98
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Schrader valves, they should, look near aircompressor supplies. if not, pick up a lame one from an auto store, or bike shop.


PS, love the avatar man.
There are rules, and then there are hundred dollar bills.
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Counterstriker
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Thanks man! haha yes igrenade.. peace put!

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Fnord
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If you have a small, privately owned tire shop around, chances are you can get some schrader valves for free. If you ever have to go to there to get tires or anything else, ask the guys because they probably have tons just laying around.
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Counterstriker
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Ok I will be back from Home Depot in like 1 hr.
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mark.f
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Well, if you're still here hanging around...

If you want to shoot marbles, don't go with 1/2" PVC. (BTW, whoever said 3/4" PVC on the previous page is wrong). While marbles fit in this pipe, it is a little loose.

If you want a near perfect fit, look for some 1/2" type M copper tubing. You actually have to sort your standard bag of marbles into the kind that fit this tubing and the kind that are too big. You can either solder a 1/2" male adapter to the end of the tubing or you can attach a 5/8" compression nut to the end.


As for Schrader valves, look in the automotive section at Wal-Mart. They'll have both 1-1/4" and longer Schrader valves, that come in packs of two for about one-and-a-half dollars. Simply drill a 1/2" diameter hole through your chamber during construction where a coupling overlaps the pipe. Push the neck from the inside and out. Grasp the stem with a pair of pliers and pull hard and twist until a rubber bead pops out of the hole. After this, you're done. It will not leak, (unless you've got a REALLY crappily drilled hole), and it will not go anywhere. Basically, it's shaped like this:

<img src="http://www.markfh11q.net/images/tireschrader.gif">
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Counterstriker
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I am freaking mad...the stupid people at lowes know nothing about there job..They are over priced for 1 and the didn't have the right size...How do you have a 2 inch air resevoir to fit in a 1/2 inch barrel? well if you use fitting they had absolute nothing!...

please i need help! I know no one really tells you how to make one but i really don't wanna waste money
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mopherman
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Dont talk to the people at the hardware store. They dont know anything.
As for the 2>1/2 thing: get a 2 coupling, a 2-1 reduce brushing, and a 1-1/2 reduce brushing and put em all together.
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Counterstriker
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Thankyou!..Can someone tell me a more indept way to install a airvalve..
the one i bought is like a little than a half an inch ..But its completely metal and not at all rubber. It has the one side with the threads and the other side has very little threads..i am confused...
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VH_man
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one side should have a little thingine sticking up inside of it. you dont want to install that side into the gun. stick the wider part into the gun, the one that your bike pump wont fit onto.
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