6 ms·

I used to think these were really cool and harmless fun as a teenager. Then at college, some guys I knew made one (and they weren’t dumb at all, pretty competen

I used to think these were really cool and harmless fun as a teenager. Then at college, some guys I knew made one (and they weren’t dumb at all, pretty competent people). They were firing it near where people were sitting on the lawn and it suddenly shattered, sending sharp jagged pieces of PVC flying. One of the pieces hit a girl sitting nearby and gave her a nasty cut near her eye. Her face was covered in blood and it was totally horrific for her and everyone else. It made me realize that the fun of the activity was just significantly outweighed by the possible safety downside. It could have been so much worse, too— she could have been blinded instead of just gotten a nasty scar on her face.

spike021 2y ago
I think the key is using them in an open space away from people and where you can have some measure of safety. My friends would use theirs in an uninhabited valley off a ridge.
- eigenvalue 2y ago
  Yes but even then the person firing it is at risk. At a minimum you should use serious eye and face protection.
  - macNchz 2y ago
    When my friends and I made these 20 years ago we leaned into the "cannon" vibe and mounted them on sawhorses held down with sandbags, then the ignition was on a wire so you could step back to fire it. At the time I think it was... not about safety so much as it just seemed cool to do it like that, but I guess that's one way not to actually be holding the thing while it fires.
    - lazide 2y ago
      Notably, cannons also used to sometimes explode randomly when fired.
petee 2y ago
With a good sharp chunk you can potentially nick someones artery. We had a couple incidents and nobody got really hurt, but later I came to the same feeling of 'fun, but no thanks'
- RajT88 2y ago
  The potato itself has enough energy to cross several football fields. That's enough to possibly kill someone if it hits their chest.
ggreer 2y ago
These sorts of failures are usually caused by people constructing the potato cannon out of thinner schedule 40 PVC (usually colored white). If you use schedule 80 PVC (which tends to be dark gray) or ABS (which deforms instead of shattering), the risk is negligible. This is also why I prefer pneumatic cannons to combustion. Since there's not a quick spike in pressure from a combustion reaction, the maximum pressure that needs to be contained is lower (and you can measure it with a gauge as you're pumping the air tank up). Also if you make the air tank big enough, the pressure behind the projectile stays high for longer, so you tend to get higher velocities. When I was in high school I made a potato cannon, played around with it in the woods with some friends, and then told my parents about it. My mom wasn't too happy, but my dad took it as a challenge. He built an even more powerful pneumatic version with a tripod, sights, and a solenoid trigger mechanism. The whole family loved it. I used some extra PVC pipe to make molds for cement slugs. With a little paper wadding to get a good seal, they'd go fast enough to embed themselves a couple feet into the side of a hill. It was spectacular.
- ryandrake 2y ago
  Yea, Home Depot PVC doesn't belong anywhere near compressed air. I knew a guy who wanted to outfit his garage with several compressed air drops for air tools and used plain old white PVC. Big mistake which he realized when one of the fittings shattered and launched a metal quick-disconnect through the garage door and out into the street. Thankfully nobody was in the line of fire. Please don't use PVC for air under pressure.
  - jvanderbot 2y ago
    Id love to make more potato cannons but my main issue is exactly this. I have no idea what the pressures are, what materials would work, etc. It's all folklore and bravery
    - doubleg72 2y ago
      Not really.. you can find standard ratings for pipes all over the place. I just ran air lines in my garage and it was fairly simple for me to get online and see that I needed type m copper based on the pressure I'm at. Wasn't cheap, but neither is aluminum pipe and now i have a nice reel in the center of the garage. There's a bit more to calculating the pressure when exploding hairspray in an enclosed vessel, but I'd be willing to bet just as easy information to find.
andrewstuart 2y ago
As I kid we had die cast spud guns that had a barrel width of maybe half a centimeter - pretty harmless. But today of course it would be a problem cause its guns and a problem because its a waste of food.
- burnished 2y ago
  Quit making up problems to bitch about.
  - yinser 2y ago
    I know this isn’t HN decorum but it just makes comments like these even funnier. Thanks for saying it lol
deleted 2y ago
[deleted]
youcantcook 2y ago
[dead]
chubs 2y ago
I fooled around with these too, 20+ years ago... this happened a few times to me. I took to wrapping them with a towel + gaffa tape as mitigation. The things you do as a kid!
b33j0r 2y ago
Oww. We were a bit more mythbusters, but still very unappreciative of the forces we were playing with. When I was a kid, my uncle absolutely shredded his kids’ plastic playplace (his kids, my cousins, were accomplices rather than victims). But those holes were 6 inches circular and even broke some chunks of brick wall (less impressive). I evolved it to pneumatic with my friends, and frankly that scared the crap out of us more. In retrospect, must have felt sort of like the uneasiness of being on the Titan. At any moment pressure could have instantly exploded us. Eyes, guts, something bad. However, it was totally kosher! ;p We had denim jeans and duct tape around the combustion/compression chamber, like the internet said. I think my friend claimed he smoked banana peel from the Anarchist’s Cookbook around the same time. True science, really. (Haha… it was scary as hell, and we stopped after a few weeks of terrifying afterschool experiments. The banana kid also claimed he was making a nuclear weapon after stealing plutonium from “this science guy’s house”) PS: none of us ever wore safety glasses. Dumb luck, emphasis on dumb.
bogota 2y ago
Maybe don’t stand next to others when firing it… so yes they were dumb. But more so the general mentality of “a bad thing could happen so lets never do it” is sad to me.

spike021 2y ago

I think the key is using them in an open space away from people and where you can have some measure of safety. My friends would use theirs in an uninhabited valley off a ridge.

eigenvalue 2y ago
Yes but even then the person firing it is at risk. At a minimum you should use serious eye and face protection.
- macNchz 2y ago
  When my friends and I made these 20 years ago we leaned into the "cannon" vibe and mounted them on sawhorses held down with sandbags, then the ignition was on a wire so you could step back to fire it. At the time I think it was... not about safety so much as it just seemed cool to do it like that, but I guess that's one way not to actually be holding the thing while it fires.
  - lazide 2y ago
    Notably, cannons also used to sometimes explode randomly when fired.

petee 2y ago

With a good sharp chunk you can potentially nick someones artery. We had a couple incidents and nobody got really hurt, but later I came to the same feeling of 'fun, but no thanks'

RajT88 2y ago
The potato itself has enough energy to cross several football fields. That's enough to possibly kill someone if it hits their chest.

ggreer 2y ago

These sorts of failures are usually caused by people constructing the potato cannon out of thinner schedule 40 PVC (usually colored white). If you use schedule 80 PVC (which tends to be dark gray) or ABS (which deforms instead of shattering), the risk is negligible. This is also why I prefer pneumatic cannons to combustion. Since there's not a quick spike in pressure from a combustion reaction, the maximum pressure that needs to be contained is lower (and you can measure it with a gauge as you're pumping the air tank up). Also if you make the air tank big enough, the pressure behind the projectile stays high for longer, so you tend to get higher velocities. When I was in high school I made a potato cannon, played around with it in the woods with some friends, and then told my parents about it. My mom wasn't too happy, but my dad took it as a challenge. He built an even more powerful pneumatic version with a tripod, sights, and a solenoid trigger mechanism. The whole family loved it. I used some extra PVC pipe to make molds for cement slugs. With a little paper wadding to get a good seal, they'd go fast enough to embed themselves a couple feet into the side of a hill. It was spectacular.

ryandrake 2y ago
Yea, Home Depot PVC doesn't belong anywhere near compressed air. I knew a guy who wanted to outfit his garage with several compressed air drops for air tools and used plain old white PVC. Big mistake which he realized when one of the fittings shattered and launched a metal quick-disconnect through the garage door and out into the street. Thankfully nobody was in the line of fire. Please don't use PVC for air under pressure.
- jvanderbot 2y ago
  Id love to make more potato cannons but my main issue is exactly this. I have no idea what the pressures are, what materials would work, etc. It's all folklore and bravery
  - doubleg72 2y ago
    Not really.. you can find standard ratings for pipes all over the place. I just ran air lines in my garage and it was fairly simple for me to get online and see that I needed type m copper based on the pressure I'm at. Wasn't cheap, but neither is aluminum pipe and now i have a nice reel in the center of the garage. There's a bit more to calculating the pressure when exploding hairspray in an enclosed vessel, but I'd be willing to bet just as easy information to find.

andrewstuart 2y ago

As I kid we had die cast spud guns that had a barrel width of maybe half a centimeter - pretty harmless. But today of course it would be a problem cause its guns and a problem because its a waste of food.

burnished 2y ago
Quit making up problems to bitch about.
- yinser 2y ago
  I know this isn’t HN decorum but it just makes comments like these even funnier. Thanks for saying it lol

deleted 2y ago

[deleted]

youcantcook 2y ago

[dead]

chubs 2y ago

I fooled around with these too, 20+ years ago... this happened a few times to me. I took to wrapping them with a towel + gaffa tape as mitigation. The things you do as a kid!

b33j0r 2y ago

Oww. We were a bit more mythbusters, but still very unappreciative of the forces we were playing with. When I was a kid, my uncle absolutely shredded his kids’ plastic playplace (his kids, my cousins, were accomplices rather than victims). But those holes were 6 inches circular and even broke some chunks of brick wall (less impressive). I evolved it to pneumatic with my friends, and frankly that scared the crap out of us more. In retrospect, must have felt sort of like the uneasiness of being on the Titan. At any moment pressure could have instantly exploded us. Eyes, guts, something bad. However, it was totally kosher! ;p We had denim jeans and duct tape around the combustion/compression chamber, like the internet said. I think my friend claimed he smoked banana peel from the Anarchist’s Cookbook around the same time. True science, really. (Haha… it was scary as hell, and we stopped after a few weeks of terrifying afterschool experiments. The banana kid also claimed he was making a nuclear weapon after stealing plutonium from “this science guy’s house”) PS: none of us ever wore safety glasses. Dumb luck, emphasis on dumb.

bogota 2y ago

Maybe don’t stand next to others when firing it… so yes they were dumb. But more so the general mentality of “a bad thing could happen so lets never do it” is sad to me.