air powered cannon?

[niverson92]

I just wanted to get some opinions on an idea that I have had for a new geocache for a while.

 

I am sure you all have seen the air cannons you can make using a few pieces of PVC pipe and a ball valve. My question is: Would you think using one of these to shoot a container of some sort (film canister or bison tube) into the air be a good idea?

 

I know these things can be pretty dangerous but I would make sure to secure it in a way that it can only be fired straight up so as to avoid injury from the container taking out an eye while coming out.

 

I also know that some geocachers don't go after geocaches that require them to bring a special tool with them, I wanted to add to the challenge and require them to bring the bike pump out to GZ in order to operate the cannon.

 

I have seen many geocaches that use pressurized air to extract a geocache but none in this fashion. I have also seen many that use a spring to shoot the cache into the air in the same way.

 

I couldn't find anything in the guidelines about this kind of cache so could it even be published?

 

Just looking for input and possible ways to make it safer.

[+Sharks-N-Beans]

Can't quite understand how this would work. If the cacher has to get close enough to reload, someone is going to have their face at the end of the barrel when it fires...Murphy's Law.

[+ngrrfan]

I am sure you all have seen the air cannons you can make using a few pieces of PVC pipe and a ball valve. My question is: Would you think using one of these to shoot a container of some sort (film canister or bison tube) into the air be a good idea?

{snip} Just looking for input and possible ways to make it safer.

Best way to make it safe is for you to be there to operate it.

[+Mr. Wilson & a Mt. Goat]

I don't think an air cannon would be a good Idea, but if you want something similar, I've seen a cache where the film canister was shot out with a spring, similar to pinball.

[GOF and Bacall]

When asking if a certain cache idea would be allowed the best place to start is by reading the guidelines. After that if you still have questions ask your reviewer.

 

The idea of some sort of air canon cache launcher makes me think of 'A Christmas Story'. "You'll shoot your eye out, kid."

[+Fiver1]

Plain and Simple === Bad Idea!!!.

 

If someone isn't posted at the cache 24/7 365, how's it going to work? Who reloads it? Do you seriously think people would be responsible enough to operate something like this on their own? Jeez, for the most part a huge group of them can't properly close a ziplock bag or a lock-n-lock.

 

I think your thought on this is pretty interesting, but impractical.

[+OZ2CPU]

>Jeez, for the most part a huge group of them can't properly close a ziplock bag or a lock-n-lock.

 

X 1000 :-)

 

or put the darn geo sticks ON TOP of the cache.. not UNDER the cache, how hard is stuff out there ??

[+NYPaddleCacher]

Sounds like someone just saw an episode of "Punkin' Chunkin'"

[+Bushwalker53]

As long as you warn them to wear a helmet! If it shoots it too high, as the bison tube is coming down it would be just like a bullet, and possibly kill someone. I have seen caches on youtube like this that used a spring. Don't make it shoot too high or you could hurt someone, maybe put padding on the bison tube as a precaution? It depends on the area and the reviewer. Maybe use a spring instead. Hope this helps.

Edited February 23, 2013 by Bushwalker53

[+T.D.M.22]

NO NO NO NO NO!!! Between the air pressure, and temp changes, and being in the sun, the PVC WILL weaken and fail. Plus it may be considered a weapon, and leaving a weapon outside for everyone with a smartphone to find is a bad idea-if someone misuses it you may be responsible. How are you going to pressurize it? Plus it could be sabotaged/vandalized. If you use a paintball air tank and something's wrong with the tank it could kill someone-some of those tanks are up to 4,500 PSI(Your car tires are about 31PSI)

 

There are ways to do something similar with a spring(We have one were I live)-If you PM Me I could even provide you with a diagram that you can use for the base design, then you can decide on the cosmetics for yourself. I'd rather help you then have you build something like this.

[+MartyBartfast]

Am I the only one who spotted

 

I wanted to add to the challenge and require them to bring the bike pump out to GZ

 

So if it's going to be pressurised with a bike pump it ain't gonna be running at a pressure that would kill anyone, and it's not likely to injure anyone - although I suppose there's always the risk of getting something in the eyes.

 

Not saying it's a good idea though.

Edited February 23, 2013 by MartyBartfast

[+murrayegger]

Well if you tone it down to not be much stronger than a spring powered one. I would use some sort of a regulator to limit the pressure or an automatic (air not battery powered) dump valve that dumps at x psi.

 

The problem is resetting. You need to be able to access the muzzle to reload. You want the muzzle to be somewhere that eyes won't be in the way. Draw up a design and see what you can come up with.

[+LightHouseSeekers]

My visualization of this possible cache has a valve on the bottom to attach the air source ie. bike pump. The container that is inserted has a gasket to keep the air in the pipe, pressure pushes (not shoots)it from the pipe. Sounds cool, not dangerous.

[+Fiver1]

My visualization of this possible cache has a valve on the bottom to attach the air source ie. bike pump. The container that is inserted has a gasket to keep the air in the pipe, pressure pushes (not shoots)it from the pipe. Sounds cool, not dangerous.

 

If that's the case then it's not a "cannon". If the intent is to just push something far enough out to retrieve, then there shouldn't be a problem. Wonder how long that Schrader valve will hold up though.

[AZcachemeister]

So many cool ideas that really are not possible due to practical reasons.

 

As previously stated, getting finders to properly reset the thing will be 'difficult'.

 

I want a cache where you lean on the correct tree branch and the tree opens up revealing a circular staircase to the underground bunker.

 

Only in the movies my friend, only in the movies.

[+simpjkee]

So many cool ideas that really are not possible due to practical reasons.

 

As previously stated, getting finders to properly reset the thing will be 'difficult'.

 

I want a cache where you lean on the correct tree branch and the tree opens up revealing a circular staircase to the underground bunker.

 

Only in the movies my friend, only in the movies.

 

Underground bunker? Definite guidelines violation!

[niverson92]

I wasn't really worried about the container flying out at a high velocity because the set up I have now is capable of putting out ~25-35 psi which is just enough to have it come out of the barrel.

 

as for the resetting part I don't see how it would be much more difficult to reset than a spring mechanism. In my opinion a spring mechanism would be more difficult because with my idea all you'd have to do is turn the ball valve back into place.

 

I knew when I posted this that I would get a lot of nay-sayers simply because of the word cannon.

 

This isn't a pumpkin chunkin' type cannon it isn't even capable of putting out that much power.

[+Rainbow Spirit]

I have a similar cache GC23ZVC and it uses what everyone will have with them, their lungs. It consists of some 50mm (2") PVC pipe, two pieces about a metre long, joined at their base with a short connecting piece. Set vertical and tied to a tree. You blow down one piece (the other is cut jagged) and a light weight aluminium vitamin tube pops up out of the other tube. To prevent the container jamming a small piece of metal fly mesh is at the bottom of the container tube. Also there is a very small hole at the base to let out water, and in fact that is another way to release the container.

[AZcachemeister]

Well, why are you asking us?

 

Go ahead and do it and let the local community tell you if it's a good idea or not.

 

I foresee problems.

But, I have been wrong before...

[+CanadianRockies]

I have a similar cache GC23ZVC and it uses what everyone will have with them, their lungs. It consists of some 50mm (2") PVC pipe, two pieces about a metre long, joined at their base with a short connecting piece. Set vertical and tied to a tree. You blow down one piece (the other is cut jagged) and a light weight aluminium vitamin tube pops up out of the other tube. To prevent the container jamming a small piece of metal fly mesh is at the bottom of the container tube. Also there is a very small hole at the base to let out water spit, and in fact that is another way to release the container.

I think I'd let my caching buddy have the honors of operating this one.

[+wvmarle]

 

Underground bunker? Definite guidelines violation!

Absolutely not. I have at least one cache hidden in an underground bunker (hillside, level access).

 

Of course I did not do any digging to place my cache. The Brits did that part, well before WW2.

 

Now if you thinking of digging a bunker to use as cache container... that falls foul of the guidelines. However if you do just that on your own land, or somewhere you have express permission, it may just be permissible anyway.

[+jellis]

There is one in our area. Works great and it shot a bison with tail on the end. It only flew about 10ft. I have been told the pipe was above ground but I didn't see it but could be under the ground cover along the bottom of the fence. So if you do this make sure you are NOT DIGGING a trench for the pipe.

[+Packanack]

You will put your eye out.

[+Gitchee-Gummee]

Let me get this straight...

 

You are gonna have people do this, when many of them cannot even change/pump up the tire on a bicycle?

Many (so it seems) cannot properly close a Lock & Lock...

 

Methinks you are asking a bit much.

[+Ma & Pa]

There is one in our area. Works great and it shot a bison with tail on the end. It only flew about 10ft. I have been told the pipe was above ground but I didn't see it but could be under the ground cover along the bottom of the fence. So if you do this make sure you are NOT DIGGING a trench for the pipe.

 

I think we did that one last week. You pump manually in one spot and the bison flies out of a tube about 15 feet away. The pipe is above ground along the fence on the other side of the fence.

 

Great cache

[+akkatracker]

I have seen something similar to that and took a small video (not very good)

You load the pressure using a handle and release the pressure with a fire extinguisher, firing the object up.

[+jellis]

There is one in our area. Works great and it shot a bison with tail on the end. It only flew about 10ft. I have been told the pipe was above ground but I didn't see it but could be under the ground cover along the bottom of the fence. So if you do this make sure you are NOT DIGGING a trench for the pipe.

 

I think we did that one last week. You pump manually in one spot and the bison flies out of a tube about 15 feet away. The pipe is above ground along the fence on the other side of the fence.

 

Great cache

Pipe to the fence and the bison maybe above ground but he still had to DIG a hole for the air compression part which is on private property of the business.

[+maxx borchovski]

My view is that if you read in the logs that someone was hurt using your cache, lost an eye or such like. How is that going to make you feel? Using air pressure to reveal a container is ok, it's been done several times very well. Shooting the container out is asking for trouble, I'd not like to have to explain a cache like that to the police officer knocking on my door after some muggle kid blinded himself whilst he was tampering with it.