Carbide Cannons

[RUUUUUN]

Has anyone here ever messed with carbide cannons?

 

What are carbide cannons? They are the fireworks/salutes of the future! This extremely safe cannon simulator uses a couple of drop of very common ingredients to create a very loud and safe report. These things are so safe that the original creators of the toy used a GLASS cannon to demonstrate how safe it was, and to create a nice flash show. one really interesting feature is the fact that you get very little recoil for the size of the bang. If you buy one online they run ya about 150 USD (batteries not included) that is a total RIPOFF, anyone with a hardware store and 3 stubs can create one, all you need is a length if pipe, a cap, some acetylene gas (normally produced VIA calcium carbide hence the name), and a match! (some assembly required)

 

I had some spare time yesterday so I welded one up out of three inch seamless steel tubing. I bored two 10mm holes in the base to get plenty of air introduction. After all this I placed 1 gram of powdered (a littler smaller than table salt) calcium Carbide (CaC2) in the chamber, added 3mLs of Hydroxyl acid (hard to come by 'round here), waited ~4 seconds, and touched a lit match to one of the air intro holes and was satsified by a nice hollowy BOOM that echoed a few times. I was suprised that it worked the first time and jumped about 2 feet..... Now, I am aware that this is not optimal, there have been cannon that have exceeded 200 dB, and I am trying to get mine there.

 

Anyone else out there every messed with one of the neat toys and have any tips for making mine louder?

[WarezWally]

Not really, but I've seen a metal water pipe with one end welded shut be filled with a oxy-acetylene mix and a lit splint poked through a hole in the side. Very percussive for such a small thing.

[Saind]

I live in the Netherlands, where carbide cannons are pretty much a national sport.

We use "melkbussen" as cannon, but for bigger cannons really every big pipe will do the job.

I say, search on youtube for "carbid schieten" , "melkbus schieten" or "carbid kanon".

[Pretty green flame]

We, Slovenes, shoot with carbide on easter, around a kilo of calcium carbide is dropped into a 150l steel barrel and water poured over it. The gas is ignited with a long stick that has a burning rag at the end of it, it is ignited through a small hole that has been made prior to the shooting.

 

[OneEyeCharlie]

Oy! Did someone say cannon?

 

Anyone else out there every messed with one of the neat toys and have any tips for making mine louder?

 

Depends on the size of your expansion chamber. It's a bit of trial and error to get the ratios of water vs carbide correct to get maximum diffusion of the gas prior to ignition.

 

Conveniently for me, mine drops a precise amount of Bangsite into the chamber with a push of a button. What can I say... I'm lazy.

 

anyone with a hardware store and 3 stubs can create one,

 

True, but it lacks a certain panache. Look at that beauty below. You can almost hear the cannons thundering at Verdun or Liege or Sevastapol or Muskegon.

 

Happy Easter everyone. Wait.... the ground just shook. That must be PGF touching off 2 lbs of carbide

[RUUUUUN]

Anyone here ever tried to powder carbide? Its like trying to grind up gravel! I tried a blender and accomplished little except destroying the jar. Currently I pour ~20 grams onto our welding table and put a steel plate over it and hit it with a hammer a whole bunch of times. ANyone have any better/faster Ideas for powdering it?

 

Charlie: Where it lacks panache it makes up when the price 'free' comes up on the price tag, I got all mine pipe as scrap and "inherited" the carbide when my dad found the can and said "WOAH, I haven't used that in like 25 years!"

Also, I think i am going to try make a larger one so I can get a larger expansion chamber which should yeild a higher decibel report.

 

Ever tried launching anything out of yours? I put a piece of duct tape over the muzzle of mine and it didn't even blow it off, it went BOOfffsshshhhhhhh as the flames started shooting out the air vents.

[Saind]

You should avoid hitting carbide with a hammer.

The fragments could hit your eye and react with the moisture in the eye, which is pretty crap.

[oskarchem]

You should avoid hitting carbide with a hammer.

The fragments could hit your eye and react with the moisture in the eye, which is pretty crap.

Wow... You know pyro is a dangerous hobby, a shell could blow up in tour hand... It is possible

[justanotherpyro]

You should avoid hitting carbide with a hammer.

The fragments could hit your eye and react with the moisture in the eye, which is pretty crap.

Wow... You know pyro is a dangerous hobby, a shell could blow up in tour hand... It is possible

Yes it is dangerous. Which is exactly why we take so many precuations. My glasses have saved my eyes plenty of times. Its only after something shoots into your eye and a $2000 hospital bill that you think it might have been a good idea to wear a faceshield.

 

Granted there are bigger things to worry about than a piece of CaC2 in your eye but nonetheless its still a notable safety issue.

 

Another method you might try to crush it is to use a press if you have one. If you can break down pieces with steady pressure it keeps things from flying, cuts down on dust, and prevents the unpredictability of smacking things with hammers.

[OneEyeCharlie]

I hear ya loud and clear with regards to the free part. I happen to be at that point in my life when I have more money than time.

 

The carbide "inheritance" was a good score. I've been looking for chunk carbide for an old miners lamp that I have. Use to have a pound can of it laying around, but I'll be buggered if I can find it?!? It probably disappeared during one of my wife's periodic clean-up urges.

 

My carbide cannon shoots a cork quite a fair distance. During the summer, I let my kids dink around with it. The barrel is fitted loosely to the expansion chamber, so a significant amount of theoretical propulsion leaks out.

 

If I need to lay down any suppressive fire at the neighbors; I fall back on my 1/4 scale garrison cannon featured in a different post. Greg the Accountant scurries in fear anytime he sees me setting up in defilade near my hammock

 

Its only after something shoots into your eye and a $2000 hospital bill that you think it might have been a good idea to wear a faceshield.

 

As someone who can remove his right "eye", I can't stress enough the importance of eye protection. Sure, the chicks dig a guy wearing a black, leather patch, but you gotta trust me on this one... it's not worth it.

[RUUUUUN]

The press is a good Idea, I have a 20 Ton arbor for pressing rockets, I am gonna haveta get a coupla pieces of thin steel and press the carbide between that.

 

@ saind: I wear eye protection (full blown lab goggles) while hitting it, also hearing protection, but that is more because it is really loud hitting a steel welding table with a hammer....

 

Has anyone here made the reaction chamber somewhere else (probably only a few feet/inches away) and pumped the acetylene into the cannon, then fired it. I am trying to cut down on all of the chalk I get in the cannon, it is quite messy, if I could keep that in a seperate sealed bottle and just pumped the acetylene in it would be much cleaner, albiet not as cool. Running with this idea, I was thinking of pumping the acetylene into one side and the oxygen into the other and then being able to rapid fire (every 5 seconds probably, with really high pressure such as hooking up a gas welding apparatus(sp?) maybe every 3 seconds) the cannon for the fourth.

[hst45]

Charlie, take a look at this link:

 

http://civilwartalk.com/Field_Artillery/p2_articleid/77

 

My goal for the summer is to buiid a 1/2-scale 1857 Napoleon. Yard-art doubles as salute cannon. I've already scrounged a piece of 3" sprinkler pipe for the barrel, and I'll either sleeve it with 1/2" or 3/4" iron pipe, and fill the space in between with grout. I've pretty much worked out the scale drawings for the carriage, but I haven't figured out the elevation hardware yet. I'm going to use #6 bar for the spokes, and I'm not sure how that will look, but I don't have the patience to make wooden spokes by hand with a spoke shave, or to turn them on my old mans lathe when I can weld them up in an hour. Since you are our resident cannoneer, any advise on concept and fabrication is appreciated.

 

Boomingly yours, hst.

[GalFisk]

Oxy/acetylene is a quite different beast from air/acetylene, I wouldn't mess with the former unless I knew exactly what I was doing. It goes from deflagration to detonation very easily.

[Sylar]

where air/acetylene will make a nice boom, oxy-acetylene certainly has that high explosive character where it can rip apart seamless steel tubing!!

 

Shrapnel anyone?

I've seen empty soda cans be obliterated at school from a knocked out welder flame, the body shredded to pieces, the bottom turned inside out and torn, and the top never to be found!

[KinneticEnergy]

Please don't try to use oxy-acetylene! While visiting my grandmother in South Dakota, I learned the power of this stuff through my uncle. He used an acetylene torch to fill a balloon partway with the gas, then put in pure oxygen, he then tied the balloon to a yard stick. He then took a torch and touched it to the balloon... Not only did I FEEL the concussion wave from 15 feet, but my ears were ringing for around 20 seconds after(not to mention my uncle).

[Mumbles]

Well, that would be your fault for being a moron and being so close. You probably would have felt the concussion from 100 feet.

[FrankRizzo]

Attaching a oxy/acetylene filled balloon with a section of fuse delay to a helium balloon is quite fun.

[crazyboy25]

I happen to be at that point in my life when I have more money than time.

Sometimes I wish I was at that stage in my life but then I realize I'd be bald...(bad genes)

 

If I need to lay down any suppressive fire at the neighbors; I fall back on my 1/4 scale garrison cannon featured in a different post. Greg the Accountant scurries in fear anytime he sees me setting up in defilade near my hammock 2ninja.gif

 

Sometimes I don't know if your kidding or serious, either way your hilarious.

 

I'm not really into cannons my self but I do wish I had some calcium carbide, mmmm acetylene.

[Frozentech]

where air/acetylene will make a nice boom, oxy-acetylene certainly has that high explosive character where it can rip apart seamless steel tubing!!

 

Shrapnel anyone?

I've seen empty soda cans be obliterated at school from a knocked out welder flame, the body shredded to pieces, the bottom turned inside out and torn, and the top never to be found!

http://gizmodo.com/gadgets/explosions/and-...less-156801.php

 

http://www.lampton.com/safety.htm

[RUUUUUN]

Aight heah da dealio, after reasearching a bit more I found that a larger chamber reduced to a smaller barrel will yeild a much larger report. Using said info I got a 4" tube 10" long, with a cap and a reducer, and a 15" length of 2". I bored a 10mm hole about 5/8 inch above the cap. Once it had all setup I put 2 grams of powdered carbide in the chamber, added 20 mL water, waited 10 seconds and touched it off. Luckily for me, I was wearing ear plugs, because when that sucker went off, it was loud in the ear plugs.

 

I am now going to experiment with less carbide, until I have a nice equalibrium between add powder and touch it off (build suspense for my buds)

 

Anybody know if it is safe to use PVC for a carbide cannon, because HDPE is a pain in the neck to get, and expensive. I am aware of all of the safety features entailed, but I am still owly about sticking and air/acetylene mixture into PVC much less glass.

[Sylar]

HELL NO !!!

 

PVC (as we all know) makes shrapnel that can't be detected using x-rays and provides continuous infection hazards! I'd rather have metal shrapnel in me then pvc.

 

 

This thread is going straight for the potato-cannon losers and should be shredded, burnt, compacted, encapsuled in 2 feet concrete and tossed away in the Mariana trench imho.

[GalFisk]

Acetylene/air is not safe in PVC, it's too brittle. I'd go with steel or copper tubing instead.

Edit: don't diss potato cannons Sylar, there's much more to spudguns than sticking a potato and some hair spray in a PVC pipe. Visit spudtech.com for tons of info and some truly spectacular cannons.

[TheSidewinder]

Spudding has its followers in the WPAG, too. The farmer who tends the field West of our site is probably going to harvest potatoes as well as corn next year.

[RUUUUUN]

I was thinking, if I didn't glue the PVC so that the end cap *should* come off before the pipe blew, and I fired it remotely from about 150 feet.

 

I want to make a whole bunch for the fourth and enact an old-style artillery volley, and I don't really have the funds to create 20 or so cannons out of HDPE atm.

 

How/where did spud-guns enter the conversation? This is about carbide cannons which are noise simulators, I am well aware that they probably would make a great spud-gun, but if anyone wants to talk about spudguns and exotic propulsion, make your own dang-ed thread and don't pollute mine, please!

[jacob]

PVC (as we all know) makes shrapnel that can't be detected using x-rays and provides continuous infection hazards! I'd rather have metal shrapnel in me then pvc.

 

Actually the thing about PVC pipe not showing up on x-rays is just an old wives tale, modern PVC pipe has so many impurities, colorants, flame retardants, ect, that it shows up just fine on an x-ray, pure PVC might not, but pipe definitely does.

 

And why would it pose a bigger infection hazard then anything else?