nevermind, i found it

its called GGDT, great program

anyone know the name of the program that you can enter your cannon specs, and see the ratio of the barrel to chamber and how fast it is leacing the barrel etc

I remember using it last year, but cant find it on my pc anymore

Thanks for the help

Bruno

thanks so much, i am learning why this is not as powerful and also the pumpkins are fairly light, like a 120 grams, so they should be capable of going about a 100 yards, a 2" sprinkler valve is quite expensive, so i am going to pass, but i will make a piston valve on my net building, probably after ...

okay thank you

i dunno if i will have time to build a new one but for future reference i might design one and see what you think of my design

i think i may just spray paint an apple orange, that way when they see me quickly stick it in they will never know what it was, plus it goes so fast, no one ...

they are almost perfectly round, like a baseball, and i would add some slight wadding for a best possible seal.

The piston valves look really complicated to make, so i might stay with a ball valve, since i already have everything cemented together, maybe for my next cannon

Would a piston valve ...

I was just wondering if i can use any type of spray paint or do i need a special kind for the pvc pipe

Any recommendations?

thanks, i was hoping for like 500 feet or more

any other opinions??

how can i make it reach about 600+ feet??

Thanks Bruno

I have a a air cannon that i want to change a barrel from a 2" to 3" piece. I currently have a 7ft piece and would make the 3" 8-9ft long as well.

My chamber is a 4" diameter with a distance of 6 feet and using a 2" ball valve

i want to launch little pumpkins that weigh about 120-130 grams

At ...

thank you for that, i thought i had an idea but i was way off and it wouldn't have worked

I am going to try and set it up and post pics of my first cannon built.

I want to put a threaded barrel on teh end but i have found a female 2" to 2" threaded piece but can't find a 2" threaded into a 3 ...

What type of spring should be used?

i tried searching google for spring loaded ball valve and got nothing

well, i have asked people but if it is something that if you have never done before or used before you don't know how it works.

I have built many others things like trebucheuts that were 25 feet tall and this came up as a school project.

If you want to send it to me you can, but i really don't ...

you can send it to my email bruno6491@yahoo.com if you want and im still confused how a wire and pulling a pin will have enough force to open the valve

I did add another 3 feet to my barrel and noticed an improvement in distance

Thank you for your efforts in trying to post a diagram but i have looked it over read it many times and asked people but still confused

If you can post a diagram, i am thankful, just want to have it done by the 25th, when ...

So is my chamber too big or too small when i pressurize it?

I will be adding a threaded piece so i will have interchangeable barrels, just slipped my mind yesterday at HD

I saw the post on the spring loaded vlave, but could not follow what you were saying. If there was a diagram or even a more ...

what if i already used the primer purple stuff and cement glue, is there a way to get it out of the ball valve or just when i build another one?? Can i use a 2" coupler and just add more 2" pipe?

I thought it was a 4:1 just volume, never anything pressuirzed

Any ideas on the ball valve spring idea ...