SpudFiles

I'm building a large pneumatic that utilizes four 1" sprinkler valves, would i just go ahead and do the logical thing? Taking the pipe nipples in the valves and leading air hose from them to three T-shapes with an airblow gun on the middle T? or is there something else im overlooking? I basically want 4 valves to go off at once, but i don't want any of the valves to open before or after the others. can you help me with this problem?

thanks,
Flinchy

It would be way eaisier and cheeper to just not mod them and use a solinoid but if you really wanted to pneumaticly actuate them you couldn't use a blowgun you would need a pretty big ball valve.

Consider running the tube from the pilot on each valve to a fifth sprinkler valve used to fire the four main valves. You could hook it up using Ts and hose barbs. This would be fast, and would gaurntee that they'd all fire at the same time.

Just an idea.

Peace,
Pete Zaria.

Bluetooth, a ballvalve could be used, but i want the fastest possible triggering with the valves, and i just believe that ball valves get annoying.

and Pete Zaria, i like your idea a bit better, but how should i trigger the 5th valve? and also wouldn't it leak because those valves only seal at 20PSI or higher? if you visit this part again please leave some feedback on this.

-flinch

I have a friend with a cannon that has 4 sprinkler valves, pneumatically triggered by a 5th one. The 4 main ones are 1" valves, the trigger valve is a 3/4". He triggers the 5th one with the provided solonoid and a switch. The 4 main ones are conected to the 5th one via 3 Ts and hose barbs. It seems to work fine for him. I've never tried it myself.

Peace,
Pete Zaria.

The 5th valve in the setup wouldn't leak because it would be under the same pressure as the chamber of your cannon. If you do go with a 5 valve setup you should trigger the 5th valve pneumatically. Also you might look into a Supah Valve from Joel SpudTech they are about $150 but 5 sprinkler valves could easily cost you that much.

i have seen the supah valves that joel makes. sadly their a little out of my price range. im trying to build this cannon for no more than $160.00, parts, valves, barrels and all. ill be using four of those black 1" watermaster sprinkler valves. they look like this.

http://www.cornerhardware.com/images/20/20704.jpg

its the one with the manual bleed valve and the flow control on the top. is it possible to remove the flow control and insert a pipe nipple with the hose connected? or do i have to do some further modification first? if you are unsure of the valve im talking about copy and paste the link above into your browser and take a look at it. if any of you have modified a valve similar to this please let me know, and if you can give me a few pointers on it, thanks .

Flinch[/url]

How-to page for flow control sprinkler mod. According to that you just take apart the valve and rip out the control knob, also good luck with your cannon!

thanks torch , that clears up a mess. this cannon will be costly, but once its all finished and after i show it off in the school soccer field to my physics teacher by launching some coconuts accross the 500 yard field ill post it with pictures and all. this will be my first addition to the cannon album, and hopefully not the last.

-Flinch

Thats what, a 4'' barrel? Cant wait to see it!


P.S. Try some cement filled coconuts!

you would have better performance with 2 piston valves, either 4" with 3" porting which would be amazing, or 3 inch with 2.5 or 2 which is still very strong. Also, much easier to rig up.

yeah its a bit easier for some people to rig up, i havn't built any piston cannons yet, but thats for the future. im building this one with everything i know about cannons so far, which is a fair amount. also about the coconut, i think it would fly furthest if i took two 3" endcaps and wrapped alot of ducttape around the sides of them to make them fit the 4" barrel, then i put one cap down, drop in the coconut, and put the other on top. it would be awesome, and after the shot i can retrieve the cracked coconut (hopefulyl cracked) and drink the sweet nectur of the coconut, or in this case throw the remains in the barrel and blow them to kingdom come.

-flinch

So long as the pilots are connected, the backpressure from the barrel will garentee that the other valves open at the same time.

I'm not quite sure what you mean by that blb...

The reason that all the valves would open together is that you're venting the pilot vloume on all of them at the same time. I don't think the pressure from the barrel really was anything to do with it. But the trigger valve would be at the same pressure as the rest of the cannon, because when the valves equalize the air pressure will fill the entire pilot volume including the the trigger valve.

I would go with 2 piston vavles. But if you are going to use sprinkler valves, go with 1/2" PVC for the triggers, this way there is a 1/2 pilot instead of 1/4. And try and use a 1'' ball valve for the trigger.