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Potato Bazookas

Posted by CmdrTaco on from the in-times-of-desperation dept.

Zog The Undeniable writes "The latest craze in Germany is "Kartoffelkanone" or potato bazookas. These use hairspray ignited by a spark to fire potatoes at colossal speeds. The authorities are not amused." Everyone needs a hobby I guess.

12 of 623 comments (clear)

  1. Building instructions by giel · · Score: 4, Informative

    For anyone interested in doing this too, building instructions can be found here

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    giel.y contains 2 shift/reduce conflicts
  2. or for an aliternate site... by AmigaAvenger · · Score: 4, Informative

    Not like no one else has done this on the net. Here are detailed instructions (at least enough to build) if you are so inclined... http://blizzard.rwic.und.edu/~nordlie/cannon/

  3. I'm making one when I get home by vasqzr · · Score: 5, Informative


    Old, but very sweet!

    GotSpud?

    Tony's page

    Spudweizer

    Simple Spudgun

    My mom would never let me build one when I lived at home, so now's my chance. AND, I'll be prosecuted as an adult, and possibly an 'American Terrorist'

  4. Re:Behind the times... by G-funk · · Score: 4, Informative

    I find it's easier to simply get a matching diamater chunk of potato and put it in the freezer for a day :)

    frozen oranges are good too if you've got the right diamater pvc

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    Send lawyers, guns, and money!
  5. hair spray is for wussies by schematix · · Score: 5, Informative

    It just so happens I had this same hobby a few years back. Except we used propane as the fuel and golf balls as the projectiles. Tiger Woods beware! It was truly amazing to see a golf ball launched several hundred yards, almost out of sight. For those interested, www.spudtech.com has a load of information on these fun toys.

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    Scott
  6. Hairspray is for girls by Slightly+Askew · · Score: 5, Informative

    Hairspray is for wimps...real men use compressed air. Compressed air is much more powerful, you don't have the legal ramifications of using an explosive, and it's cheaper than hairspray. It takes a little more work to get it air-tight, and you have to buy a thicker PVC pipe, but the results are worth the extra effort.

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    Public use of any portable music system is a virtually guaranteed indicator of sociopathic tendencies. -- Zoso
    1. Re:Hairspray is for girls by Technician · · Score: 4, Informative

      use compressed air and hairspray or starter fluid combined I have no idea how the valve would work on that one. Combustion cannons have no valve and compressed anything would expell the spud. I wouldn't want a closed valve on a compressed combustion cannon. Can you say gernade?

      From testing I found an air cannon with a piston quick exhaust valve has about the same performance as a propane/air cannon of the same size when the air is operated at about 40-50 PSI. At 100 PSI it is no longer a contest. For some reason the propane cannon is much noiser, but the air cannon is much more powerful.
      A friend and I did a comparison about 2 years ago. Both cannons had 2 inch barrels with an overall length of about 8 feet. The air cannon used a piston valve 2-1/2 inches in diamater that directly seated on the 2 inch breech of the barrel inside the air chamber. This provided an air orfice the diamater of the barrel. Look up quick exhaust valves for details of the valve operation. The 8 foot length in both cannons is a safety feature. It's almost impossible to get any body part over the end of the barrel while operating the trigger mechanism.

      I prefer the air cannons for safety reasons. They can be hydrostat tested so you know they are not likely to blow up when used at about half the test pressure. You just never know with a combustion cannon. As always, follow some safety guides including pressure testing and ensuring the downrange is clear. My current pnumatic is tested at 150 PSI and operated in the 60-80 PSI range. Holes in 3/4 plywood are no problem to make.
      A roll of adding machine tape shot into the sky is a sight to behold. It unrolls on the way up and tears into dollar bill size pieces until it looses enough speed to unroll the remainder without tearing. It's a confetti storm of dollar size pieces with a 60 foot streamer at the very top. It's also realtively safe if used in an area with lots of spectators. There are no heavy high speed objects falling out of the sky to injure a spectator. The 8 foot length pointed up keeps onlookers from trying to look down the barrel while charging. It's best to eliminate the plastic core from the roll of paper before use.

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      The truth shall set you free!
  7. Re:Behind the times... by kris · · Score: 4, Informative

    No, german kids have always been building things that go boom, as did kids all over the world. It is the german magazine DER SPIEGEL which discovered the topic and decided to make it an issue just now. Seems to fit with the overall mood, US going to war in Irak and weapons inspections and all.

    Kristian

  8. Re:I had one... by bmwm3nut · · Score: 4, Informative

    even better, acetylene. any hobby store sells calcium carbide (the stuff in old miner's helmets to make the light). just put a little calcium carbide in water and you have instant acetylene (used for welding). ignite that with a gas grill ignitor and you can easily have potatoes going 150mph. when i was little my brother and i experimented with many different style guns. the best we came up with was using acetylene as the propellant and using a 1 inch pvc barrel (rahter than the traditional 2 inch). you couldn't shoot a whole potato with it, but the part you did shoot went about 150mph. (we figured that out by timing how long the potato stayed in the air when shot vertically).

  9. Obligatory letter from the ATF Re: Spud Guns by swordboy · · Score: 5, Informative

    Here's a letter from the ATF regarding the legality of the "spud gun". Note the date - September 12, 1995.

    Definitely old news...

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    Life is the leading cause of death in America.
  10. Good point. by Andy+Dodd · · Score: 4, Informative

    It sounds like these have gone from "geek hobby" to "mainstream danger"

    Good thing most of these kids are probably too stupid to make a pneumatic spudgun. Far safer for the operator, but FAR more dangerous for people at the wrong end of the cannon. (Pneumatic spudguns use a constant pressure for most of the firing cycle, rather than the quick spike of pressure from combustion. As a result, pneumatics can pack a LOT more power into a gun while stressing the components less.)

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    retrorocket.o not found, launch anyway?
  11. A local museum has one by S&W by gordie · · Score: 4, Informative

    Down in Dunedin FL, there is a local museum dedicated to Police and the Military. http://www.naslemm.com On display is a spud gun manufactured by the engineering department of Smith & Wesson over 20 years ago. Big, Blue and with the S&W Logo, a bit more impressive then the tennis ball cannons, I used to build back in the 70's.