SpudFiles

After the success of my first cannon I'm itching to build another one. Only this time I want MORE P WER! I'm thinking about a triple valve design. You might be asking yourself.....why would someone want to do this? and the aswer is......because I can, waahahahah. At least when the wife finally lets me......(end evil laughter)

Is a triple valve design overkill?

I plan to mod the valves so all three release at once with a blow gun. I haven't decided how I want to route the pilot so for now it's not included in the concept. Everything will be 2" pvc with 1" valves.

Any feedback positive or negative will be appreciated. I want this to be as powerful as I can make it without using a piston. Oh, and the barrel will be longer. I figure the the air chambers will be about 15-20" long with a 40" barrel. I want to be able to hold it to fire it.

Without further delay I give you "The Triple Threat"!
<a href="http://s273.photobucket.com/albums/jj23 ... 081918.jpg" target="_blank"><img src="http://i273.photobucket.com/albums/jj23 ... 081918.jpg" border="0" alt="Photobucket"></a>

Oh, and it took me like 3 hours to do the shading on her upper lip!

First off using a blowgun might work, but you'd really be pushing it. Idealy you should pilot those with another sprinkler and pilot that with a blowgun. I actualy really like the design you have, but ass you said a longer barrel is good, remember 1.8/1 is a good chamber to barrel ratio. A good thing is also get some reducers, so you can put on different barrels, this realy expands the uses of a gun. Another thing is the 3 separate chambers. Filling all 3 individually would suck. But I think you could also screw a shrader into the pilot sprinkler and use that to fill em all. Just expect it to take a long time to fill.
I guess thats all, any more questions?

Piston Valve. (message too short)

ImHUGEnJAPAN wrote:I want this to be as powerful as I can make it without using a Piston.

You miss that?

iisthemuffin wrote:

ImHUGEnJAPAN wrote:I want this to be as powerful as I can make it without using a Piston.

You miss that?

???

elitesniper said to use a piston valve when you had already said you didnt want to. I was pointing that out to him.

iisthemuffin wrote:elitesniper said to use a piston valve when you had already said you didnt want to. I was pointing that out to him.

oh, never mind......I should learn to follow the conversation...LOL!

Haha. Yea that may help you out a bit.

Well, then, burst disk, or a controlled one if you want the most power.

I would consider improving flow from the valves to the barrel. It looks rather constricted at this point. A manifold made of 2" might help out. I as well think you should use a fourth sprinkler valve to trigger the other three.

Though it will match a piston valve, there are some flaws.
My thoughts about it:

-It will be as powerful as a piston valve if done right.
-Its kinda bulky.
-It will be a waste of money (very expensive).
-The T-piece where the two front sprinklers get together, and the T-piece where that T connects to the 3rd sprinkler needs to be barrel diameter so it not constricts flow. (recommending a cross piece! That way you will minimize dead volume)
-The two tanks on the front are way smaller then the back one and thus the sprinkler on the top has to give more flow.
-You will need another sprinkler to pilot all those valves together.
-You could use a longer barrel. Make all tanks equal.
-Dont be afraid, piston valves are not hard to make, and way cheaper (and easier then using 3 sprinklers)

psycix wrote:Though it will match a piston valve, there are some flaws.
My thoughts about it:

-It will be as powerful as a piston valve if done right.
-Its kinda bulky.
-It will be a waste of money (very expensive).
-The T-piece where the two front sprinklers get together, and the T-piece where that T connects to the 3rd sprinkler needs to be barrel diameter so it not constricts flow. (recommending a cross piece! That way you will minimize dead volume)
-The two tanks on the front are way smaller then the back one and thus the sprinkler on the top has to give more flow.
-You will need another sprinkler to pilot all those valves together.
-You could use a longer barrel. Make all tanks equal.
-Dont be afraid, piston valves are not hard to make, and way cheaper (and easier then using 3 sprinklers)

-All the tanks will be the same size 15-20" in length the drawing is not to scale.
-The barrel will definately be longer 30-40"
-The cannon will be bulky, but that's ok.
-I'm not worried about the Money $75-100 will not break me.
-I certainly need to optimize the dead space to make it flow better.

-I plan to make several barrels for this as well. (I won't glue my threads to the barrel this time around)

I might just redesign this using 2 valves
-

you do realize that sprinkler valves are not very efficient. and for a 1" sprinkler valve its like $15 where you can build a cheap 1" piston valve with 2-4x more flow than a sprinkler.

Ok so you want to minimize dead space... its just not piratical to keep adding sprinklers onto it.

but if you have money to blow and want to blow it... then go for it.

It will have lots o' power. To reiterate pschix advice, add a 4th sprinkler and blowgun trigger (or even electric if you want) to become your master pilot for the other 3. Build up a little manifold and pipe the 3 pilots into the master sprinkler inlet.

Also, make your plumbing larger directly after the 3 sprinklers ...plumb up to 2" where the 3 sprinklers mix.

Edit: Nice upper lip shading there...

ImHUGEnJAPAN wrote:I want this to be as powerful as I can make it without using a piston

In that case, longest barrel you can manage, at least a 1:1 chamber to barrel ratio, the highest pressure you can use and buy a single 2" or 3" sprinkler valve, with the barrel in line with the chamber.

Multiple valves are not a good idea, not only will they actuate at different times - tiny, tiny differences, but your projectile only spends a small fraction of a second in theb arrel - but by introducing flow from different directions, you're creating turrbulence which cuts down on power. Not to mention the dead space...

That's my 0.02 euros worth as far as power is concerned, but I must admit your design does look funky