Any Punkin Chunkers out there?

[anickode]

I've been watching the annual Discovery Channel Punkin Chunkin specials on netflix recently, and it's been giving me the itch to try it out. I've built air cannons of every sort to launch all sorts of stuff. Nothing that big before though.

Anybody around here who has previously or is planning to compete this year?

[ThorsHammer]

I'm more the Trebuchet type myself, that being said I have yet to chunk my first punk, but it'll happen. Still in the design stage of my trebuchet so it's still all small scale.

[anickode]

Trebuchets are definitely cool. I'm definitely an air cannon/centrifugal guy though.

I've got a design in mind that would in theory give far better performance from a shorter barrel and smaller tank than many of the huge 2000+ gallon tanks with 100 foot barrels. It's all about the valving.

[Dualie]

i threw a punkin out of an suv going 75 once does that count?

[jbmprods]

Originally Posted by Dualie

i threw a punkin out of an suv going 75 once does that count?

i hope you did better than my high school buddy did off the back of my 52 international 1 ton flat bed when we were bombing mail boxes. we cut off his drinken when he forgot to let go of the punkin. thank god it was a wood 4x4 post that was rotten at the base cause at 50 mph he did a sweet body slam on that puppy lol.

[Dualie]

Now that i would love to see! we also threw one of of a 150 condor man lift just to see what it would do.

[socoj2]

Originally Posted by anickode

Trebuchets are definitely cool. I'm definitely an air cannon/centrifugal guy though.

I've got a design in mind that would in theory give far better performance from a shorter barrel and smaller tank than many of the huge 2000+ gallon tanks with 100 foot barrels. It's all about the valving.

Only so much. Unless you wanted to do Helium.

Air has a fixed Expansion rate so even if you have a 100% efficient Valve with the same orrafice as your pipe you are still limited by the barrel size.

[anickode]

Originally Posted by socoj2

Only so much. Unless you wanted to do Helium.

Air has a fixed Expansion rate so even if you have a 100% efficient Valve with the same orrafice as your pipe you are still limited by the barrel size.

Official chunkin rules prohibit the use of purified industrial gases for chunkin. It's compressed air or nothing.

Besides... It would take about a blimp's worth of helium to fill a cannon like that, which will likely NEVER be in my budget.

The efficiency and diameter of the valve is the most important thing... followed closely by the quality of the air you put in it. (moisture content being the key factor)

Most of the cannons out there use a pneumatic ram attached to a butterfly valve, and while that's faster than you could manually turn the valve, there's a LOT of improvement to be had.