Econogun III

[yuandrew]

I've been a potato cannon enthusiast for a while but just recently found this site. I've started out when a friend of mine showed me the cannon he made which got me hooked. Well, as always, I wanted to build one but at that time about 5 years ago, I didn't have the time or the money to buy the parts.

I ended up looking around in my garage and backyard for any junk I had around and ended up building a cannon out of a soup can (Swanson Chicken Broth) and a piece of 3 inch diameter landscape drain pipe (ABS but white on the outside; inside is black) It was too big for a potato but oranges and some water bottles would fit in it. The cannon was constructed by removing the lid from the soup can and punching a small hold in the other end with a nail then duct tapeing the can to one end of the pipe. To fire, you would spray hairspray or butane down the barrel and quickly ram you projectile down after then "light" off the fuel by sticking a burning match into the hole at the bottom of the can. It was crude but it would shoot anywhere from 40 to 60 feet real fast. I named it "econo gun" as it was real cheap

The original design soon fell apart but I kept the pipe. I tried other cannons including a "classic" one and another "econo" version this time using a 2 liter bottle and some attachment from a vacuum cleaner but the bottle melted during a shot with alcohol which kept burning instead of going out after the shot.

I rebuilt my original cannon since I kept the pipe. This time, I used an instant coffee jar but it was still duct taped on but it also had an bbq ignitor so I didn't need matches anymore. I use propane for fuel and normally shoot oranges and plastic bottles and tennis ball containers
It is now called Econogun III
PICS:

The Original


Current Design


Ignitor


Chamber


Pose


For more info and my progress visit my site
http://yu.andrew.tripod.com/econogun3/

My website on this
http://yu.andrew.tripod.com/spudcannons/

[sergeantspud2]

that looks like one that my friend show which got me into spud guning
except it didn't have duct tape on the chamber, that looks a little dagerous. and i noticed that you are not using screws for electrodes on your barbq ignitor how are you getting the spark

[boilingleadbath]

You are going to end up embarrased, maimed or dead. You have probably violated every guidline and item of common pressurized gas scence in existance.

[yuandrew]

The wires are attached to an actual ignition electrode from a bbq that looks somewhat like this

I didn't use the gas collector box or the screw; the metal round thing on the electrode has the ground wire attached to it and the positive wire is attached to the ceramic thing itself. The spark jumps from the top down the side and hits the metal ring. The whole thing just hangs down into the pipe and is secured by the wires with tape. If you look at the 4th pic, you can see where the wires go in under the tape

It does look flimsly but it hasn't blown up on me yet. I've actually shot oranges out of it that fit tightly and it's loud. I know there is now combustion chamber; the projectile goes in the pipe 2/3's of the way in and the rest of the pipe acts as a chamber. It's kind of like the basketball cannon [/list]

[saladtossser]

dude, u used duct tape??? it bursts at 5 psi!! get a clean-out!! the $3 is worth ur safety!!

btw, it would be nice of you to remove ur instruction for the "econo" gun, plz, a kid got his eyes burnt with instructions like yours, because FOR NO REASON SHOULD THERE BE A HOLE IN THE CHAMBER, hot gases will burn you badly

[sergeantspud2]

correct me if i'm rong but that pipe you're using is drain pipe that isn't pressure rated and is like less than 1/8" thick

[yuandrew]

Yes, the pipe is landscape drain pipe that is 1/8" thick. I try to avoid using too powerful a fuel and not shooting anything too big for it.

About the hole in the original gun, it's how I light it. There's either a fuse through the hole or I stick in a lit match (not with my fingers but with pliers) You don't stand directly behind that and stare at the hole when you stick the match in

ABS drain pipe is also not pressure rated but I have a friend who's dad is a plumber and he built a compressed air cannon using ABS and fires it with a 1.5" PVC ball valve that he epoxied between the chamber section and the barrel. The chamber section if I can remember is a 6" Y fitting with a 3" branch comming off the side that extends down and gets capped off and the both sides have a reducer that goes down to a 3" pipe with a short section at the back that is capped off with a fitting for an air compressor and the front end also has a short section of 3" pipe that gets reduced down to a 1.5" where it goes into the ball valve then to the rest of the barrel

Since ABS drain pipe is not pressure rated, it is scary when he fills it up at the compressor. At around 40psi it start to make creaking noises but he still keeps going. He first rams a potato in and fills it with air then he holds the Y fitting branch with one hand and quickly twists the ball valve with the other to shoot the potato.

The worst injury he told me he had with that thing was when he decided to shoot popcorn kernals and just poured a bunch down the barrel and stuffed in a paper towel for wadding. He told me the recoil was so strong that it broke his thumb on the hand that was holding the valve.

[saladtossser]

ABS is good for combustions, not pneumatics.
btw put "not responsible for loss of limbs" on ur discliamer.

[brian Casey]

for lack of better words kid all i have to say is your a moron kids die from guns like yours, if your gun explodes you could end up witha hunk of plastic in your throat. You should save like $ and buy some pipe10

[zeigs spud]

it seems like alota ppl are attacking you but really there just tryin to keep you safe lol. you may of been lucky with the cannon sofar but everything breaks eventualy and wtith that cannoni predict soon and it's gonna hurt. Medical bills are more than wht u would need to spend for a safer gun.

just lookin out for yea lol.

[brian Casey]

kid you are a moron, every year people goto the emergency room because of guns like yours, dont tell people how to make that and i would get rid of it yourself.

[ProfessorAmadeus]

I second that..... ..

[Slugfoot]

Yuandrew, you're taking risks that will no doubt get you hurt. Please, if you're going to build these things then build them with safety in mind.



Saladtosser, Arrrrr! I just noticed your sig! Be you a fellow Pastafarian then?

[Spyider]

i think that this gun should be totally dismantaled the pipe broken and you should never make another gun in yo life.

no joke thats ehh i woldentove even posted somthin like that.

i dont let my guns i make leave unless its pvc and not ducktaped together.

[Walsh_3rdE]

mate what the hell is that thing ? - a death wish ?

there is a reson why people pay the money to get a full pvc of metal cannon

addvice - take the coke bottel out of the back and put on an atucal plumbing T section that way it migh be safe .