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Author: Subject: Useing a balloon for a oxyhydrogen explosive?
ScienceSquirrel
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[*] posted on 29-1-2011 at 14:56


The Science Squirrel guide to safe gas explosions;

1) Take a 5 -10 litre balloon and fill it with the stochiometric mixture of fuel gas and oxygen. Assume that the balloon is a perfect sphere and base your calculations on this. You can allow for quite a bit in the way of errors. Your mixture can be too rich in oxygen or fuel and it will still explode. Some fuel gases are more forgiving than others

2) Tape the full balloon to a support and attach a piece of thick string as a fuse. Do this on a windless and rain free night. Light the string and retreat to a safe distance, 25 yards / metres is more than enough.

3) Watch the flash and hear the bang. It is about like a 12 guage / bore on this scale but pretty harmless as there is very little blast wave and no debris.
It is an STP gas explosion, it will make a flash and a bang, it is not going to blow you to smithereens!
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[*] posted on 30-1-2011 at 13:00


What would be a good household item to make the electrode out of, my plan is to stick something through a water bottle with the balloon on the end.
or what is a good metal to use that won't rust/ decompose




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[*] posted on 30-1-2011 at 14:08
"For fools rush in where angles fear to tread."


Oxygen - acetylene

http://tinyurl.com/4mpskdw
http://wn.com/oxygen_acetylene_huge_bomb

Man charged after explosion in Oneonta welding class
http://www.wktv.com/news/local/47519762.html

>> "gagage bag" acetylene explosion <<
yields 4 880 Google hits.... have fun.

{I was looking for the news report of the garbage bag
full of acetylene going off in the back seat of someones
car while they were driving...!}


djh
---
The explosion removed the windows,
the door and most of the chimney.
It was the sort of thing you expected in
the Street of Alchemists. The neighbours
preferred explosions, which were at least
identifiable and soon over. They were better
than the smells, which crept up on you.

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[*] posted on 30-1-2011 at 15:45


Nobody should fill garbage bags or airbeds with fuel gas / oxygen or air mixtures and ignite them.
You will have tens or even hundreds of litres of gas and the explosion will be huge and could be dangerous and might be illegal.
If you live in a country district and go for five litres or so in a balloon, it will make a safe explosion that could be mistaken for a backfire. Legally it will probably fall into a grey area or may even be legal. In the UK small gas explosions in balloons are a mainstay of chemical demonstrations so I reckon they are legal.
Really it is a backfire but not from a car! :D
Do some research, plan out what you are going to do and stick to the plan.
If it goes wrong, give up the experiment and start again.
I have done a lot of dangerous chemistry and never had a serious accident but I started off handling safe chemicals and developed a good technique.
Do it on a small scale and make it bigger if you need to and rehearse things. You do not want to do your first gas explosion in front of an audience.
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[*] posted on 30-1-2011 at 15:49


Still don't know a good metal for electrolysis, but had the idea that I could just put electrodes through a 2 litre bottle take most the air out start electrolysis and put an electronic ignition system on the cap.
With that system it could be at higher pressures than a balloon.
I have oxyacetylene cylinders at my house I might try those sometime.
Would aluminium or some screws or nails work well for electrodes?




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[*] posted on 31-1-2011 at 05:48


Ill let your assertion that approx 10% variation in volume
"is pretty flippant consisent in your world" speak for itself.

"inconsistent methods have no place on a scientific forum"





If You have determined a repeatable ,simple method of filling a balloon or plastic bag with a stoichiometric gas mix using commonly available materials thats more accurate that a neutral flame and marked valves lets hear it!(then prove it)Then Ill be dazzled by your brilliance and baffled by your bullshit.Till then...
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[*] posted on 31-1-2011 at 07:23


Quote:
Ill let your assertion that approx 10% variation in volume
"is pretty flippant consisent [sic] in your world" speak for itself.

"inconsistent methods have no place on a scientific forum"


I'm sorry, but if this is your only response to my comments, and you still believe that marking the valves on a torch will get you even close to <10% experimental error, then you are clearly too stupid to be participating in this discussion. Move on.

Quote:
If You have determined a repeatable ,simple method of filling a balloon or plastic bag with a stoichiometric gas mix using commonly available materials thats [sic] more accurate that a neutral flame and marked valves lets hear it!(then prove it)Then Ill be dazzled by your brilliance and baffled by your bullshit.Till then...


It's not rocket science. 2 valves, a trapped volume of known value, a pressure gauge, and Boyle's law are all you need. If you can't figure it out from that description, you have no business playing around with such sensitive and powerful gas mixtures.

[Edited on 1-31-2011 by SB15]




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[*] posted on 31-1-2011 at 09:30


Quote: Originally posted by SB15  
Quote:
Ill let your assertion that approx 10% variation in volume
"is pretty flippant consisent [sic] in your world" speak for itself.

"inconsistent methods have no place on a scientific forum"


I'm sorry, but if this is your only response to my comments, and you still believe that marking the valves on a torch will get you even close to <10% experimental error, then you are clearly too stupid to be participating in this discussion. Move on.

Quote:
If You have determined a repeatable ,simple method of filling a balloon or plastic bag with a stoichiometric gas mix using commonly available materials thats [sic] more accurate that a neutral flame and marked valves lets hear it!(then prove it)Then Ill be dazzled by your brilliance and baffled by your bullshit.Till then...


It's not rocket science. 2 valves, a trapped volume of known value, a pressure gauge, and Boyle's law are all you need. If you can't figure it out from that description, you have no business playing around with such sensitive and powerful gas mixtures.

[Edited on 1-31-2011 by SB15]


You have been on this forum for less than a month and have less than 20 post, maybe try to be a little more reasonable and not act like a troll.




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[*] posted on 31-1-2011 at 11:48


Quote: Originally posted by crazedguy  
You have been on this forum for less than a month and have less than 20 post, maybe try to be a little more reasonable and not act like a troll.


Are you one of those individuals who believes that post count and longevity on a forum determine one's level of knowledge?

Yeah, I've been here for a month. I'm also an engineering student with extensive experience in the field of gas explosions, and was a member of the E&W forum for 4 years before it shut down.

It just so happens that I know a thing or two about the topic of this thread, and am not subtle about conveying my knowledge of techniques that do and do not work effectively. I also expect the people who make and use energetic materials as a hobby to posses more knowledge of scientific methods than the average K3Wl who fills balloons with random gas mixtures in hopes of making a 'big boom'. If that's trolling to you, maybe you need to find a different forum to post on.

Before you question my knowledge of gas explosions, have a look at how I've applied them in the past.




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[*] posted on 31-1-2011 at 12:35
The explosion blasted out the win dows of two homes


Clearwater Times .Tuesday July 6, 2004 .‎
St. Petersburg Times - Jul 6, 2004
LARGO — The explosion blasted out the windows of two homes. ...
at a neighborhood Fourth of July party mixed oxygen and
acetylene in a plastic garbage bag, ...

http://tinyurl.com/4ezyrua


Found it.

Strange-Looking Car Leads To Explosives Charges
Balloon Filled With Acetylene Bound For Super Bowl Party

http://www.thedenverchannel.co.../6790966/detail.html


I remember an explosion in a Manhattan, NY welding supply
store. Don't be knowing if it was caused by leaking acetylene
or propane or ??

The store fronted on 52nd St between 10th and 11th avenue,
the roll down steel front gate looked like it had been kicked by Paul
Bunion. The rear of the building facing 54st backed up on to a
small parking lot. One of my fellow employees had bought a new
car and he a two other coworker were looking at. They hadn't
gotten twenty feet away - back to work when the rear brick wall of
the welding store fell on his brand new car.

One store employee suffered a broken leg. After the accident
they stored all of their tanks outside.



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[*] posted on 31-1-2011 at 12:49


This is probably my favourite F/A explosion, caused by leaking gas when the pressure dropped the operator just cranked the pressure up, the spark was cause when two trains full of children passing by each other caused sparks.
http://en.wikipedia.org/wiki/Ufa_train_disaster



Quote: Originally posted by SB15  
Quote: Originally posted by crazedguy  
You have been on this forum for less than a month and have less than 20 post, maybe try to be a little more reasonable and not act like a troll.


Are you one of those individuals who believes that post count and longevity on a forum determine one's level of knowledge?
[/url]


I really don't care what your prerequisites are trolling is trolling, I am not saying that I'm smarter than you because I have more post point is you don't just act like your better than every one else.
Ghandi-To think your better than one is to be worse than all.
You obviously don't like that someone would challenge your knowledge, maybe explain your points before getting angry and calling people names over the internet because that solves nothing.




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[*] posted on 31-1-2011 at 15:17


Woohoo, you two big darlings must really fancy each other to get all hissy like this! :P
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[*] posted on 31-1-2011 at 17:20


Quote: Originally posted by The WiZard is In  
Clearwater Times .Tuesday July 6, 2004 .‎
St. Petersburg Times - Jul 6, 2004
LARGO — The explosion blasted out the windows of two homes. ...
at a neighborhood Fourth of July party mixed oxygen and
acetylene in a plastic garbage bag, ...

http://tinyurl.com/4ezyrua


Found it.

Strange-Looking Car Leads To Explosives Charges
Balloon Filled With Acetylene Bound For Super Bowl Party

http://www.thedenverchannel.co.../6790966/detail.html


I remember an explosion in a Manhattan, NY welding supply
store. Don't be knowing if it was caused by leaking acetylene
or propane or ??

The store fronted on 52nd St between 10th and 11th avenue,
the roll down steel front gate looked like it had been kicked by Paul
Bunion. The rear of the building facing 54st backed up on to a
small parking lot. One of my fellow employees had bought a new
car and he a two other coworker were looking at. They hadn't
gotten twenty feet away - back to work when the rear brick wall of
the welding store fell on his brand new car.

One store employee suffered a broken leg. After the accident
they stored all of their tanks outside.





A garbage bag holds 70 litres in the UK. I would guess that a US garbage bag is a similar size.
No one is suggesting making gas explosions on this scale.
Keep it small, 1 -5 litres and do some research before the demo and it is safe.
There is a big difference between 7, 70 and 700 litres, scale is important in practical chemistry!
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[*] posted on 31-1-2011 at 18:23


Well yeah common sense is a must when doing stupid things.



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[*] posted on 1-2-2011 at 10:37


@ Wizard.. I believe I saw the explosion your referring to on hist
Tv.Traced to a engineering flaw ganging a couple dozen acetylene tanks to a manifold system.In any event It was spectacular.
As far as legallitys Im sure intent has a great deal to do with legality.Using a dangerous explosive gas mix device in a crowd is far different than as a target in a unpopulated western area of grasslands.

@ SB 15.. It might be helpful at this point to tone down the discussion.My opinion is that you have still not demonstrated a practical method of filling a supposedly sperical balloon let alone odd shaped containers.Every post contains requirements for more.More gauges more this that?You mention filling a container with a known volume.How have you evacuated the container to ensure you have a pure gas?Then the problem of moving that gas into the container w/o dilution etc.How do you propose to do that w/o pressurizing the container?From a practical standpoint I do not see how this is supposed to work.If that makes me as you have said stupid then draw the stupid man a picture of this device.A simple request.Even a description of how!

Versus the simplicity and built in accuracy of precision adjustable valves with scribe marks allowing the same ratio of gas every time with the aid of the constant pressure/volume requlators/high pressure tanks.A system engineered over decades to do just what we want. Deliver a known ratio of gas capable of filling any shape- size container w/o calculations resulting innacuracys.
Precision designed /manufactured to deliver the basics of successful welding, consistent pressure/volume.How is that so difficult to understand?Yes there are some subjective elements mainly the operators perc ception of a neutral flame but I very much doubt that varys among professional welders by 10%.As others have said it doesnt take a perfectly stoichiometric ratio to make an explosive gas composition.I still maintain despite my alleged stupidity my method is far more practical/repeatable than your paper dreams.
Unlike you I have done these things in actual practice safely and very effectively, not on a piece of paper using nonexistent hardware/ or actual experimentation. Paper and pen is fundamental but theres also a recognized place for empirical evidence/actual experimentation as the ultimate test as most engineers will attest and as daily life and engineering failures prove.

If you care to reply doing so in a gentelmanly manner might assist your argument greatly rather than using insulting language which doesnt speak highly of your personality or intelligence. Or perhaps you are a troll as has been suggested.
We shall see.

@ SB15,as I think you suggested a volume gauge would be more than helpful in conjunction with a regulated supply of gases.
One could fill the container with the calculated volume of each gas resulting in a more accurate mix regardless of the shape size of the container.Unfortunately this beingfb a HOBBYIST site
many here dont even have access to industrial gases let alone
oxyacetlene welding rigs/additional gauges.Calcium carbide/water..what are the resulting constituent gases there.The fewer variables the better ,thats what I see with the oxyacetylene welding rig.[Edited on 1-2-2011 by grndpndr]

[Edited on 1-2-2011 by grndpndr]
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[*] posted on 1-2-2011 at 12:06


Quote:
It might be helpful at this point to tone down the discussion.My opinion is that you have still not demonstrated a practical method of filling a supposedly sperical balloon let alone odd shaped containers.


Didn't you see the video I posted? It demonstrates rather effectively the precision of a volumetric gas meter. The projectile launcher demonstrated uses a valve that is normally calibrated to open at ~95% of the peak theoretical deflagration pressure of the gas mixture used, and the metering setup delivers very consistent operation at all pressure ranges, and with all fuel gas/oxidizer mixtures. Granted, that's a constant volume/variable pressure setup, but the method of measurement is the same as it would be here.

Quote:
Every post contains requirements for more.More gauges more this that?


Nope, I've been talking about the same thing from the beginning. The meter for each gas requires a trapped volume (2 valves is the easiest way to set this up) and a device for measuring the pressure in the trapped volume. It only becomes reasonably complicated when you're dealing with 3 or more gases at a time.

Quote:
You mention filling a container with a known volume.How have you evacuated the container to ensure you have a pure gas?


That'll only be an issue for the first few fills. Afterward, the atmosphere in the trapped volume will be comprised entirely of the gas from the supply tank, provided you keep the valves closed between fills.

Quote:
Then the problem of moving that gas into the container w/o dilution etc.How do you propose to do that w/o pressurizing the container?


You don't want to avoid pressurizing the container. The reading on the pressure gauge is how you determine the molar quantity of gas you're measuring.

Assuming the process is adiabatic, Boyle's law is used to calculate the pressure required in the gas meter, assuming we know its volume, as well as the volume of gas required at the ~0.6PSIG the balloon will contain.

P<sub>1</sub>V<sub>1</sub> = P<sub>2</sub>V<sub>2</sub>

Quote:
From a practical standpoint I do not see how this is supposed to work.If that makes me as you have said stupid then draw the stupid man a picture of this device.A simple request.Even a description of how!


Here's a crude 5 minute MS Paint rendering of what it would look like. Calculations would need to be done to account for the extra volume of the connecting fittings. I would also add a quick connect fitting to allow the metering setup to be disconnected from the rest of the setup, as the exterior of the gauges are susceptible to blast overpressure.

Nothing is to scale BTW.



Quote:
Versus the simplicity and built in accuracy of precision adjustable valves with scribe marks allowing the same ratio of gas every time with the aid of the constant pressure/volume requlators/high pressure tanks.A system engineered over decades to do just what we want. Deliver a known ratio of gas capable of filling any shape- size container w/o calculations resulting innacuracys.
Precision designed /manufactured to deliver the basics of successful welding, consistent pressure/volume.How is that so difficult to understand?Yes there are some subjective elements mainly the operators perc ception of a neutral flame but I very much doubt that varys among professional welders by 10%.


Again, welding setups are designed to supply a consistent supply of oxidizer and fuel when the gas is burning, and with zero pressure feedback into the system. You have provided nothing to suggest that stoichiometry is maintained when the flame is extinguished and backpressure is feeding into the torch head. Assuming this has no significant effect may not be wrong, but it's crude, unverified methodology. A shot in the dark, essentially.

Quote:
As others have said it doesnt take a perfectly stoichiometric ratio to make an explosive gas composition.


Certainly not. There are many ways to produce an explosion from fuel gases. Hell, filling a balloon with a random mixture of oxygen and propane/propylene/acetylene is very likely to produce a good bang. A K3Wl can also fill a steel pipe with black powder from crushed up model rocket engines and make one hell of a loud bang. Doesn't mean either method is worthy of scientific discussion.

Quote:
I still maintain despite my alleged stupidity my method is far more practical/repeatable than your paper dreams.


Well, that's where you'd be wrong.

Quote:
Unlike you I have done these things in actual practice safely and very effectively, not on a piece of paper using nonexistent hardware/ or actual experimentation. Paper and pen is fundamental but theres also a recognized place for empirical evidence/actual experimentation as the ultimate test as most engineers will attest and as daily life and engineering failures prove.


So... where did you get the idea that I've only done these things on paper? Since you obviously missed it, here's the video again:

http://www.youtube.com/watch?v=BhHvxfDg-uw

Paper dreams do not send alkaline D cells through multiple layers of 1/16" steel using only air/propane mixtures. I'm not just some number wielding theorist.

Quote:
Unfortunately this beingfb a HOBBYIST site
many here dont even have access to industrial gases let alone
oxyacetlene welding rigs/additional gauges.


Fortunately, my system can be adapted to ordinary Bernzomatic oxygen/propane/propylene tanks using fittings from any hardware store.

Quote:
Calcium carbide/water..what are the resulting constituent gases there.


Mostly acetylene, with a bit of hydrogen sulfide and hydrogen phosphide mixed in. Technical grade calcium carbide is pretty impure stuff, but the stoichiometry shouldn't be affected significant by the trace contaminates.

However, that does bring up one of the disadvantages of a volumetric metering system: You can't use acetylene. Why? Well, it has the potential to explosively decompose above 15PSIG or so, so it's not wise to pressurize it. Oxygen/propylene is what I would go with.




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[*] posted on 1-2-2011 at 12:26


Pay particular attention to the cylinder yards who have put effort into stopping gas explosions and what the results are when it unexpectedly gets out of control.

The second video is what I would consider the most interesting, as it shows a real world problem developing and, despite the authorities moving everyone a long way back, it's still not far enough. To put the weights into a US format, the cylinders weigh about as much as a person, yet are flying around like they're made of paper.

Acetylene is the favourite fuel gas of welders due to it releasing so much energy when it burns. It is also unstable under more than approximately 15psi of pressure.

That is thousand of dollars worth of gas going up. About the same amount as the laundry bill for anyone standing nearby when it started.

The last three videos show the results of mixing the gas with oxygen. And it is not something you should be attempting if you haven't been using cylinders for a good long while.

I also find it irresponsible to be making these things look so cool without noting the extreme danger involved, as these are things people can get or already have to hand, and are likely to try; using their dad's oxy/acetylene torch for example.

In the last video, for instance, it shows the snooker player running from the table as the fuse is burning.

In reality, the caravan likely wasn't even filled with the gas and the fuse probably wasn't even connected to it at that point. They have filmed him running, then filled the caravan with a hose, from a long way away, and set it off. Probably with a squibb so they don't have to go near the caravan again. I wouldn't be surprised if they also had some method of flushing the thing with air or checking if there's acetylene left in it, should it not go off and they need to go back to it. I'd add to that, they may have even stripped the caravan of the more substantial metal parts.

You can see pieces of the caravan flying past the snooker table. That is a dangerous misrepresentation of reality given the ease with which it can be repeated by kids.

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="510" src="http://www.youtube.com/embed/fesgl5Cs5FY" frameborder="0" allowFullScreen></iframe>

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="510" src="http://www.youtube.com/embed/Wg5CgNx_sJI" frameborder="0" allowFullScreen></iframe>

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="510" src="http://www.youtube.com/embed/RoatgaQrK28" frameborder="0" allowFullScreen></iframe>

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="510" src="http://www.youtube.com/embed/1gsCuQthy60" frameborder="0" allowFullScreen></iframe>

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="510" src="http://www.youtube.com/embed/uUmLe9WCXX0" frameborder="0" allowFullScreen></iframe>

<iframe sandbox title="YouTube video player" class="youtube-player" type="text/html" width="640" height="390" src="http://www.youtube.com/embed/c6ILYnp9_44" frameborder="0" allowFullScreen></iframe>

[Edited on 1-2-2011 by peach]




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[*] posted on 1-2-2011 at 14:45


Quote: Originally posted by SB15  

Again, welding setups are designed to supply a consistent supply of oxidizer and fuel when the gas is burning, and with zero pressure feedback into the system. You have provided nothing to suggest that stoichiometry is maintained when the flame is extinguished and backpressure is feeding into the torch head. Assuming this has no significant effect may not be wrong, but it's crude, unverified methodology. A shot in the dark, essentially.



Ahhhh.... with my cutting torch the acetylene pressure is 15+ psig
and the O2 even higher. You would need a really tough balloon to
get back pressure. Just adjust your torch for a neutral flame, stick
it into a bucket of water to extinguish - sign will - fill bag(s).

Want I want is a way to fill a bag with my Plasma torch!!!
Bet they could do it on the Enterprise.



djh
----
…Though the nominative diarrhea of the solar system may
have gone a little far, a well-chosen name is both
picturesque and memorable. Perhaps, therefore, it is time
to change the convention and give such a name to an
extrasolar planet. And an ideal candidate [Kepler-10b] has
just turned up—one that matches one of astronomy’s own
myths: the legendary, non-existent planet Vulcan.

…smallest extrasolar planet yet discovered. Its diameter is a
mere 1.4 times that of Earth, though it weighs 4.6 terrestrial
masses.

…its high mass probable means it is made of iron, an
appropriate material for a planet named after a divine
smith.

The Economist
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[*] posted on 1-2-2011 at 16:20


I was just watching that second video again and noticed that at 0:34, there are plumes of thick black smoke pouring out of the cars parked in front of the yard. And it looks like it's coming from the windows of the cars.

The insides of the cars are on fire, yet there is a distinct lack of things on fire or broken around them.

INSURANCE JOB!

---------

Wizard, you are a strange and amusing man, as I have likely said before. ;)

To put a rest to the oxy/acetylene torch debacle, one could simply try filling balloons with the torch out and then light the torch to see how the mix is combusting. Welders will look for a perfect mix based on the configuration of the cones and also how the flame behaves when put against something.

One method I've heard of guys using is to simply set the flame to rich to begin with, wave it over some metal, to deposit carbon, then raise the O2 content until it will burn off the carbon and back it down a little.

The are a number of variations on that, based on whether or not it will produce reducing or oxidizing results when something is heated in the flame.

Alternatively, watch the gauges as you add the balloon for an increase in the pressure the second stage reads. Or fill a none elastic container and then push the gas into the balloon.

Short of hooking your source or generator up to a gas chromatograph, you're not getting much better.

With acetylene being so unstable under pressure, you are likely going to get more exciting results from treating it to the loving care of a high pressure shock wave. Precisely how it behaves, and how filling balloons affects the back pressure, I must admit, has never crossed my mind as a particularly important issue as I get my card out to pay for another cylinder of the two.

When a roughly ideal mix will do the things demonstrated in the video above, I fail to see why a number of you are so concerned over the remaining few percent.

I'm not even sure why you'd really want to be doing that in the first place.

If you want to make a loud bang or blow something up, there are vastly superior alternatives. You'll never match the energy density of a solid explosive using these gas mixes. And why do you want to blow something up? Unless you're mining, I don't see much use to that. The irony being, they use fairly simple stuff for blasting.

So... I don't get it.

[Edited on 2-2-2011 by peach]




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[*] posted on 1-2-2011 at 21:39


Its called a regulator for a reason.

Alright to my question that has yet to be answered,
what would make a good anode or cathode or both.
From these household metals or say one that I may have forgot.
copper, zinc, lead, aluminum, stainless, brass, tin, pot metals
so which would be best electrodes?
Thanks in advance




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[*] posted on 1-2-2011 at 23:10


Im sorry best electrodes for producing what (gas)?I missed that.
And a few other points.:D

FWIW i thought the discussion after advising we(SB/Myself) tone it down a bit far more productive.I think everyone had good points particularly safety.I know these things are very dangerous Im only proposing a 1-2 liter balloon size as a target.Still very unpleasant to have detonate next to you quite possibly perforating an eardrum/causing burns if close enough.
Similar to a primary in many ways except I dont think the gas mix will vaporize a couple fingers/hand.Still NOT to be taken lightly and not yet something ive tried but seriously considered.
If you have looked at the cost of the commercial binary tgts you might understand my interest.

In retrospect likely a bad Idea.

In a perfect world w/adequate funds a system could be designed
that operated remotely OT fitting the balloons to nipples and filling them with the appropriate gas mix.Of course someone would shoot a hole in a gas line w/o steel plate protection:(

Many of you seen test videos of high pressure cylinder penetrate a concrete block wall w/o detonation deflagration but By gas pressure alone the heavy cylinders are launched at amazing velocity/kinetic energy.If ignited a RP(Gas)C!
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[*] posted on 2-2-2011 at 04:52


I have filled balloons using cylinders; just slip it over the nipple, part fill the balloon with hydrogen, pinch the neck and slip it off the nipple, slip on to the second nipple and add a shot of oxygen. Then slip it off and tie the neck.
Optimum ratio is somewhere around 2:1 hydrogen to oxygen but as anyone who has popped hydrogen in a test tube will know it is not critical.
You can fill a balloon from a welder as well. Just slip it over the end and add some acetylene, then put a shot of oxygen in, slip it off and tie the neck.
Ratios are not critical in gas explosions, really you can judge it by eye with a bit of experience.
As long as you stick to balloons and use a modicum of care and common sense thay are noisy but very safe.
If you start filling up garbage bags, plastic or glass bottles or caravans :(
You are going to be one sorry maimed or even dead little bunny!
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[*] posted on 2-2-2011 at 09:06


The gas I want to produce is hydrogen and oxygen by electrolysis of water.



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[*] posted on 2-2-2011 at 09:46


Hydrogen diffuses through rubber quite fast.
I think you will find that it will diffuse out at such a rate that you will end up with a balloon filled mostly with oxygen, unless you put a lot of current in electrolysis is quite slow.
Why not do the logical thing and use sodium hydroxide and aluminium or such like?
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[*] posted on 2-2-2011 at 18:19


Zinc/HCI reaction?
Zinc from an alkaline battery casing/acid from Hardware.
Used this to fill balloons as lighter than air as a boy.Hindenburg
minus the aluminized airplane dope covering :(
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