Ball valve VS. Sprinkler Valve?

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Pieguy14
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Sat Jan 31, 2009 11:09 am

What should I use for my next project? Even though Im working on a Ball Valve cannon ( because this is my first EVER made cannon... )
Here are 3 questions.

1. Which one releases more air?
2. Which is more convenient for a trigger? I have made a trigger system for my cannon, and it is o.k
3. Is there any pressure limits that either one can go up to? as in a plastic 2 liter bottle can go up to 120 psi ( or that's what I've heard. ) Can a sprinkler valve blow up because too much pressure?
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spudtyrrant
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Sat Jan 31, 2009 11:33 am

1.) sprinkler valve releases more air then ball valve when modded and about the same when unmodded
2.) their is no comparison a sprinkler valve is much more ergonomic.
3.)the ball valves and sprinkler valves are usually pretty close in pressure ratings. you don't want to take a pvc sprinkler valve over 120psi(although i have heard of them being taken to 150psi) you should not take a pvc cannon over 120psi anyway. they can explode that is why you follow pressure ratings
if you want to wait a little longer and order online I would use a q.e.v(quick exhaust valve) no modding required, work extremely fast, are easy to configure into a design, and usually cost about as much as a sprinkler valve :wink: you can get them from mcmaster-carr
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starman
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Sat Jan 31, 2009 11:49 am

They will all release the same amount of air. The key is how fast they release the air.

Since this is your first cannon, I would suggest continuing on with a ball valve. Get a good win under your belt and some shooting experience.

Then a modded sprinkler could either replace your ball valve or be the basis for your next gun.

If you must toy around with a 2 liter bottle, keep the pressures lowish, in the 50-60 psi range. Why not build a proper PVC chamber?
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sputnick
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Sat Jan 31, 2009 11:54 am

I agree with starman, people always seem to want to go with something cheaper, AKA pop bottles, but it severely limits the potential and safety of your gun, just build a pvc chamber, they are not that expensive, and its better in the long run.

Also, pvc chambers are not going to be crumpled or damaged from just everyday use, go with PVC and build a gun to be proud of :)
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Pieguy14
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Sat Jan 31, 2009 12:03 pm

Ok, how would I make a pvc chamber? Just take a 2 inch piece of pvc and put caps on it?
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sputnick
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Sat Jan 31, 2009 12:05 pm

well a cap on one side, and then reducers to your ball valve on the other,


Be carefull not to use DWV, check that none of the fittings you buy say DWV on them, those are not pressure rated, after that you are all in the clear. Do you know how to properly solvent weld pipes together?
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Pieguy14
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Sat Jan 31, 2009 9:19 pm

Uh, Yea, Im pretty sure how to do that :D
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sputnick
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Sat Jan 31, 2009 9:23 pm

well you never know, you don't want people going around using super glue or duct tape,
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MrCrowley
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Sun Feb 01, 2009 7:46 pm

A sprinkler valve wont blow up unless you dump 400PSI+ pressure into it quite fast.

They're rated for 125PSI usually, probably can take up to 200PSI. But I would never take PVC over 150PSI as a general safety rule. I don't care what it's rated for. (Excluding PVC 1" and below).

A sprinkler valve will open faster, but has less flow then a ball valve of the same size. So a sprinkler valve would be better, but if you had a long barrel, say 7', the ball valve might be better because although it opens slower, it has more flow. With a longer barrel, hopefully the projectile would still be inside the barrel by the time the ball valve is completely open.

A sprinkler valve is far easier to trigger.

To make a chamber is simple. DO THE RESEARCH. If you don't know how to glue a few fittings together to make a chamber, you haven't done enough research. Go to Home Depot and spend an hour fiddling round with all the parts to get an idea of what fits in what and how.

Also read this:
http://www.spudfiles.com/spud_wiki/inde ... _Rated_PVC
Pieguy14
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Wed Feb 04, 2009 1:02 am

Solvent welding is just putting pvc primer and pvc glue on a piece of pvc inside and out, and mashing them together for an airtight seal :)
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