I want to make a cannon, strictly for a noisemaker. Google has a lot of info on these, some of them shoot bowling balls a couple of miles. Just wondering if anyone had made one, and hints or caveats. I'd like to use a piece of 8" plus or minus pipe, or a dead 300 cylinder. I prefer a propane/oxygen one over a black powder due to cost. Help appreciated.
The beer-can mortar I made was done out of some industrial offcuts of big equipment hydraulic cylinders I had. Scrapyard was the major buyer from a big crawler hoe manufacturer. Chrome moly with maybe 2" thick walls. If all you want is a noise-maker, just use a 12 gauge or smaller hole and bore it out of bar stock, you don't need anything over an inch bore for noisemaking. Bigger hole=3Dmore powder=3Dmore expensive. Also more involved if you DO want to shoot projectiles. You need a BIG area downrange for bowling-ball cailber stuff. Around here they set those off where there's nothing between the firing line and the Kansas border except a few prarie dogs That shoot only happens once a year, so anything big is just collecting dust the rest of the time.
Not exactly what you asked for but.................I have made a acetylene and air or oxygen cannon out of 4 inch black plastic dwv pipe. I just used a welding torch to blow into the muzzle and then put some saran wrap over the muzzle and secured with a rubber band. The other end was a standard cap for the pipe. Tapped a hole for a spark plug and used a simple circuit that acted like a capacitive discharge into a regular auto spark coil. So I never was close when it went off. It did not bust the plastic pipe, but I would be extremely careful. The pipe was about four feet long. It was extremely loud. I would not want a louder one. I never loaded any projectile in it.
I had a neighbor that was lighting some firecrackers and throwing then down the hill onto my deck. I got the cannon and pointed it in his direction with no projectile. He immediately stopped after I set it off. It did not break any of his windows, but I should have been more cautious.
I'd think oxyacetylene wouldn't make a very effective propellant - I think it detonates, rather than simply deflagrating like BP or Smokeless; if you stuck some kind of projectile in it, I'd think it would greatly increase the odds that the pipe would blow up in your face.
If you are near any drilling, such as oilfield. Find some used drill collars, They are thick and have a large hole in the middle around 2 to 2 1/2 inches in diameter. Could possible shoot beer cans full of cement about a mile. Usually weigh about 100 pounds to the foot.
I have one out in the shed that I made 30+ years ago out of 8 straight sided steel beer cans. It is fueled with about four drops of lighter fluid and makes enough noise to attract the local law enforcement boys. Gerry :-)} London, Canada
I once made one of them from about a half a dozen two-pound coffee cans. It was quite a disappointment. It could blow that plastic lid off the end, but I never really was able to make it really loud.
Nowadays, I sit in a weld shop/machine shop. They've got O2 and C2H2 and various bottles of argon, CO2, helium mixtures, and etc. I talked to the gas guy not too long ago about getting some plain helium, and he said he might be able to just loan me a bottle.
My plan is to take a 40 gallon trash bag, fill it with helium, tie a string to it, and tie another bag to the string full of OA mix. I'd use cotton string, soak it in kerosene, and let the helium lift it and the OA bag as high as it will go, light the string, and wait for it to pop. I once inflated a plastic bag to about the size of a fist with OA and lit it with a propane torch.
My ears rang for about three days!
To the pyro folks - does oxyacetylene actually detonate, or is it just merely a very fast deflagration?
That one the other day with the soda bottle of OA just floored me. I had no idea it was so explosive. It lifted that wheelbarrow bucket 40' in the air! UFR!
-- ...in order that a man may be happy, it is necessary that he should not only be capable of his work, but a good judge of his work. -- John Ruskin
In my misspent youth, some friends of mine did the trash bag of OA a number of times. They were very careful, but it still gives me the willies when I consider what could have gone wrong. I recommend doing this FAR away from civilization. If it goes off near houses, it can take out windows.
I don't know if it's still available, but they used "dethermalizer fuse" for time delay. It was for retrieving model gliders, and burned at about
1/4" a minute. It looked like heavy cotton clothes line, with little marks on it for timing. That was connected to regular cannon fuse.
Yes, acteylene/oxygen mixes will detonate, from about 5% to 70% acetylene by volume at STP.
Above 70% it's more an acetylene detonation (pure acetylene will sustain a detonation all by itself if the radius is large enough, though it's hard to start the detonation unless there is a bit of oxygen in the mix).
For the sake if discussion, let's say a guy wanted to just run the mixed gas in from say a cutting torch head. What pressures would the hypothetical perpetrator set the gauges at to get that mix? Would about a ratio of about
25/1 oxygen to acet be about right? Or go a little heavy on the acet, and use about 4/30?
I have a cylinder of helium we use on balloons for parties and such. I imagine a large bag of that for lifting, then about 20' of good mono fishing line down to the mixed gas bag, then the cotton/cannon fuse configuration on the bottom of that. I'm thinking I could get quite a height in about five minutes of cotton fuse.
A good carburetor man, working with an OA welder, could figure out the best stoch mix.
I'd imagine that would be high enough to involve the city, county, state, FBI, and Air Force investigators, Steve. A weather balloon could probably be heard in the next county.
-- It is characteristic of all deep human problems that they are not to be approached without some humor and some bewilderment. -- Freeman Dyson
My brother once blew the door off his shop with a small balloon filled with OA. He says to adjust your torch for a non-oxidizing and non-reducing flame, then just knock the flame off. The gas mix coming out is close enough to stoich to do the job. Art
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