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Acetylene mixed with nitrous oxide...

Posted: Mon Jan 01, 2007 12:41 pm
by beergut
Anyone ever try Acetylene mixed with nitrous oxide?
I’m thinking I might try this combo with my steel cannon I’m building in a built-off with rna_duelers.
I’ll be welding up ¼” thick steel pipe 4" dia. & a fuel delivery system from a propane fueled fork truck…should be fun!

If my knowledge serves me correctly... NO2 displaces the O2 and makes a better oxidizer... (which is why when inhaled you get high...well, actually you're asphyxiating the brain of oxygen)

Posted: Mon Jan 01, 2007 1:05 pm
by Bluetooth
It would work but be extremely powerful and unstable. I wouldn't do this unless your far away and using remote ignition. I would just use propane and oxy or propane and nitrous or substitute propane with MAPP gas. Acetylene is too unstable when pressurized.

Posted: Mon Jan 01, 2007 8:19 pm
by FiveseveN
(which is why when inhaled you get high...well, actually you're asphyxiating the brain of oxygen)
Actually, no. http://en.wikipedia.org/wiki/Effects_of ... n_the_body

If you actually think you can build a strong enough cannon and put safety first, maybe it would be worth it. If not, it's your funeral.

Posted: Mon Jan 01, 2007 8:25 pm
by pyromanic13
hahahaha.... go for it. I WANT A VIDEO!

Posted: Mon Jan 01, 2007 8:58 pm
by beergut
Fiveseven- that's a cute piece of info you found on wikipedia, but you should do more research before you attempt to correct some one. :wink:

Far before depleting the body of b12 will you die from brain asphyxiation.
Breathing pure nitrous for more then a few minutes at a time will just about deplete your blood of all usable oxygen, this is why when it's used in the medical field it's always mixed with oxygen. I worked in the medical field for quite some time and I know this.

if you do a more in depth search about the gas you'll soon read this yourself...

If you choose not to believe me do a Google search for yourself on "nitrous oxide asphyxiating the brain of oxygen"

Here are two quick quotes from knowledgeable sites:

"breathing pure nitrous for more than a few minutes will starve brain of oxygen, usually resulting in death."

and-

"Nitrous oxide actually increases respiratory rate, according to two of my resources. Nitrous oxide, administered alone (that is without supplemental oxygen) can cause asphyxiation, due to oxygen deprivation. This is because the body cannot utilize the oxygen molecule in N2O to supply oxygen to the tissues. This lack of oxygen leads to cell death.

The lack of oxygen to the brain also causes the light headed feeling and vivid hallucinations...aka "getting high"

and... any mechanic will tell you (correctly) the reason why pro-mod cars go faster with nitrous injection is because it displaces the oxygen in the combustion chamber, resulting in a hotter and stronger burn...


about the oxy / acet thing... I've built far scarier. Acetylene is small potatos (no pun intended :D ) compared to what I've worked with as a demolitions engineer in the Marine Corps for four years. I don't mean to sound cocky, and obviously all flammable gas and liquids command a savvy respect, but with the proper parts and right planning there's really no big issue with acetylene. And of course... I will share the video! :D

Posted: Mon Jan 01, 2007 10:49 pm
by Infernal2
^^^Actually no. I've worked for a decade with a harm reduction group and the likelyhood of you dying from Hypoxia is incredibly unlikely unless you are using a constant stream of N2O in an enclosed environment without taking breaks between. Sure, it can happen but you'd have to be incredibly stupid to do it. Common household ventialtion is more than ample to remove this simple issue.

Also hypoxia is not the cause of N2Os effect on the brain rather its effects as a disassociative and as a slight hypnotic. The effects of N2o are still very much debatable. Remember, even though N2O has a relatively low molecular weight it is still heavier than air so dispersal is relatively large. Keep your mouth off the stream and you'll be fine.

Remember, just because you've ridden in an am,bulance doesn't make you a doctor.

Posted: Mon Jan 01, 2007 11:22 pm
by boilingleadbath
I don't know how NO2 affects combustion rate or burn temperature... but I figure C#C would burn with it something like this:

10 NO2 + 4 C2H2 -> 5 N2 + 8 CO2 + 4 H2O
...so that makes 14 -> 17

...which would yeild pressures 40% higher than O2+C2O2's ratio of 7:6, given the same flame temperature.

(it acctualy works that way with propane too... 6:9.5 instead of 6:7 for a 35% pressure increase at the same flame temp.)

Posted: Tue Jan 02, 2007 6:47 am
by beergut
infernal- back to my original statement... breathing pure no2 will kill you within 3 minutes if a break hasn't been taken.

I've only been in an ambulance once, when I was in a motorcycle accident.
My knowledge comes from being an ultrasound technician for 6 years, working in the hospital, and a BA in biology.
You can make it sound as complicated as you like and even throw in some neat big technical terms to further enhance your statement... but it's very simple- if you are inhaling no2 for more then a few minutes, you're not consuming oxygen - you will die, and not because you've depleted your b12 reserves, and not because it acts as a hypnotic, very simply, you've suffocated. I have read more studies of teenagers accidentally committing suicide due to asphyxiating by directly inhaling no2 then I car to recall. When you have saturated your lungs with no2, you don't even have the feeling of wanting to breath (like when you hold your breath and it starts to hurt) that feeling won't be there... and it only takes minutes.

Posted: Tue Jan 02, 2007 7:10 pm
by Infernal2
^^^Yeah, that's pretty much what I said. I was pointing out that your oversimplification of the process of nitrous oxide on your brain. As well as the fact that people actually dying from nitrous inhalation are relatively few considering the extreme amounts one must have on hand to attempt death in this way. Do you need it explained in molar weight terms or via gas/blood exchange rates?

Once again, unless you have your mouth on the direct stream of nitrous for that three minutes in an enclosed space it is unlikely you will die from direct oxygen deprevation. Why? Because you will pass out before this happens. And last I knew, ultrasound technicians don't require a course in pharmacology or molar chemistry. Has this changed?

Posted: Tue Jan 02, 2007 7:29 pm
by spudmonkey
how about getin back on subject yall, isnt O2 better than N2O as an oxidizer? and i wast thinkin of doin the same thing but not for launchin stuff just for noise purposes untill i found out the power it created

Posted: Tue Jan 02, 2007 7:41 pm
by Bluetooth
No N2O is a better oxidizer.

Posted: Tue Jan 02, 2007 9:50 pm
by beergut
No Infernal2, I was disputing your statement that I must've gotten my knowledge from being an EMT...(or implying it)

If you think that working in a hospital for 6 years doesn't put you in contact with people (ya, even smart ones, but just under your knowledge base) and equipment then you can't be as refined as you'd like us to believe you are.
Many medical professionals around me...Father, brother & uncle, two of which are Cardiopulmonary Specialists -
My mother... a nurse, my sister-in-law... another doctor. I'm surrounded by'em infernal... and myself, a former hospital technician who went to school for Stenography, which is a 4 year degree program (medical / science) and a minor in biology.

Given I don't recall all the information I've read, certain things do stick, and this was one on them... Stop being a big shot and accept that what I said was a fact, and the fact is you will die if you breath nitrous for more then a few minutes.

done with it!


Thanks everyone else for sticking to the topic

:wink:

Posted: Tue Jan 02, 2007 9:56 pm
by beebs111
why would n2O be a better oxidizer than pure oxygen, im jsut not getting it

Posted: Tue Jan 02, 2007 10:22 pm
by pyrogeek
I thought part of the reason they used N2O was that due to it being cold, it would chill the incoming air, making it more dense, so you could burn more fuel.

Posted: Wed Jan 03, 2007 9:43 pm
by boilingleadbath
Oh, I'm such a fool.
I've been reading N2O as "NO2"...

Solving the propane-N2O reaction...
C3H8 + 10 N2O -> 3 CO2 + 4 H20 + 10 N2
11 -> 17

vs the reaction with O2 (C3H8 + 5 O2 -> 3CO2 + 4 H2O) which gives 6 -> 7... which isn't nearly as good (as far as pressure goes), assuming the same flame temperature.

...however, I don't know how it affects combustion rate, as compared to unaided air.