fuel question H2 O2 or Hair spray

topelitemarine · Mon Sep 21, 2015 3:16 am

H2 o2 has more explosive power or hair spray? can you compress h2o2 with household item? what kind of fuel do you guys use?

Fnord · Mon Sep 21, 2015 9:25 am

Hmm, lets see. On one hand we have a substance that's intended to keep your hair in shape, and on the other we have a substance which is liquified and used to launch rockets into space.

We have a very detailed wiki page for this.
http://www.spudfiles.com/spud_wiki/inde ... n_Spudguns

If you haven't read it yet, you're probably not ready to go about compressing oxygen enriched fuels.

topelitemarine · Tue Sep 22, 2015 1:12 am

sorry I might be wrong, I meant oxy-hydrogen. but thanks for your link now I know which fuel we use for rocket. But does the oxy-hydrogen works ? the one that extracted from water? someone say hydrogen release energy too fast will rip off the chamber that is make from pvc pipe

Fnord · Tue Sep 22, 2015 11:02 am

Oxy hydrogen is the same thing as H2 + O2... You can make it from water.
Any fuel mixed with *pure* oxygen instead of air needs to be used in a metal gun, not PVC.

If you're having trouble understanding anything, I could simplify the description and run it through a translator (if you think it would be easier). What's your first language anyway?

Ragnarok · Tue Sep 22, 2015 12:43 pm

Fnord wrote:Oxy hydrogen is the same thing as H2 + O2... You can make it from water.

Not however the same as H2O2, which would be hydrogen peroxide.

... which is indeed itself used as a rocket fuel. With the right catalyst, its decomposition rate is approximately "WHOOSHKAFROOGLEAAAARRRRGGGGHHHHIAMLITERALLYONFIRE", which is how things like the Bell rocket belt work.

But yes, as far as an oxy-hydrogen mix, it is far more powerful than hairspray, and because its combustion speed can reach detonation velocities, it does need a strong launcher. It's not something I'd really trifle with unless you've got relevant experience.
If you're looking for something a little more advanced (and considerably more powerful) than hairspray though, I'd say it's hard to go wrong with metered propane, which is considerably safer and more practical than oxy-hydrogen.

topelitemarine · Tue Sep 22, 2015 7:17 pm

What's your first language anyway?

Its okay thanks, my first language is Cantonese, which is a bunches from Chinese. Mandarin is new language only 300 years old... mine is used in ancient. I study in oversea university so I can read decent english I could understand the link that u sent me but my grammar is terrible :bounce:

topelitemarine · Tue Sep 22, 2015 7:30 pm

If you're looking for something a little more advanced (and considerably more powerful) than hairspray though, I'd say it's hard to go wrong with metered propane, which is considerably safer and more practical than oxy-hydrogen.

I will try use propane if I really get too less power with propane

because any launcher that is powered by fuel that is extracted from petroleum is illegal in my city and the launcher is design to shot hundreds of BB in airsoft game with stranger. however, I afraid sob will report to police. Since last time the sob got mad on me because I killed three of them and shot at them accidentally after they died and he want to fight with me after game.So I might use it sneaky :bigsmurf: if I really need to use propane

Ragnarok · Wed Sep 23, 2015 12:17 pm

topelitemarine wrote:because any launcher that is powered by fuel that is extracted from petroleum is illegal in my city

Well, things like deodorant and hairspray burn because they use butane to pressurize the can (or sometimes, don't burn, because some brands don't use butane), so if you're concerned about that, it could be twisted around by a sufficiently motivated prosecution. Such a restriction affects most common fuels - even things like Industrial alcohols, as they're generally made from crude oil.

If you're interpreting it strictly, I think your options do get down to things like hydrogen (but I still wouldn't recommend it), high-proof moonshine/vodka/etc (as it's produced by fermentation) or creative production of certain gases (methane is not difficult to drive off from things like coal or manure).

You might well be better off sticking with a pneumatic concept.

topelitemarine · Thu Sep 24, 2015 3:44 am

Its very strict here. Normal people can't possesses any firearm. And cannot even possess homemake smoke grenade that is make from sugar and KNO3. I rarely see any people use them in commercial airsoft field because its illegal. I really hate this I wish they give us more freedom. I am not sure how strict they are on self make cannon but it written in the law that anything fire gas, liquid or object with petroleum or by- product is considered firearms and possess firearm is illegal. I am not sure if police see this will charge me but I'm still going to make the combustion cannon for my first cannon because it's easy to make. Then I will develop a more complexity semi auto or full auto pneumatic shot gun or rocket launcher to use in airsoft game

ToasT · Thu Sep 24, 2015 5:16 am

Is this to be used in New Zealand?

If yes:
In New Zealand a firearm is defined in the 1983 arms act as "anything from which any shot, bullet, missile, or other projectile can be discharged by force of explosive" So this would include anything homemade.

It is my understanding that to own any form of firearm, a you must hold the correct license. Additionally an airgun that is powered a reservoir of compressed air (with the exception of paintball and airsoft) requires a license.
Oh, and an airgun with a 'full automatic' firing mechanism requires a restricted level firearms license.

Its always best to know the risks up front. The police are generally reasonable with their application of the law. But in the very least, don't expect to be allowed to keep anything you made if caught, maybe a fine also.

topelitemarine · Thu Sep 24, 2015 6:25 am

This is used in Hong Kong SAR , I will return to HK next month for holiday and there is no firearm licence there. No way a citizen can accesses to gun in legal way. Even fire works in prohitbited in my city. however I might bring it to New Zealand next year but I gonna focus on my exam at the moment. I tried to get a gun licence in New Zealand but I failed the exam last year and I was too lazy to sit again lol 8)

jimmy101 · Sat Sep 26, 2015 12:11 pm

Ragnarok wrote:Not however the same as H2O2, which would be hydrogen peroxide.

... which is indeed itself used as a rocket fuel. With the right catalyst, its decomposition rate is approximately "WHOOSHKAFROOGLEAAAARRRRGGGGHHHHIAMLITERALLYONFIRE", which is how things like the Bell rocket belt work.

To be fair though the same can be said for burning pretty much anything in the presence of pure oxygen. A cigarette pretty much explodes in pure O2.

H2O2 is incredibly powerful but is way way way beyond what a tinkerer could do. (And well beyond what a tinkerer should do.) You need the H2O2 to be nearly pure and in that state it is incredibly unstable. Unlike most oxidizers you don't even need a fuel with H2O2 (though it is much more energetic with a fuel).