SpudFiles

Igniting a fuel air mixture can have problems with either rich or lean mix, or explosive results. It is generally safer to dispense a small (SMALL as in a little bit) of fuel into an already burning flame. The mix does not have to be perfect as parts near the source are rich and parts far away are too lean. The boundary between the fuel stream and air will have a proper mix in small amounts so if flammable, the flame should be small in size and rapidly go out when the fuel source is shut off.

EDIT; Added example
As an example of the problem with fuel and air mixed before ignition, this video clearly shows the hazard.
[youtube][/youtube]

make a clear chamber then try to record it with a camcorder. but unless your going to figure out the A/F radio then whats the point i mean different fuel my operate at different A/F radios and isn't the point of this thread to find a easy safe way for spuders to test out witch fuel works better than others but unless spuders are willing to devote time out of there lives the test hundreds of A/F radios (witch they probably aren't) then y even have a Needs A Safe Way To Test thread.

Alright, solution goddammit:
Stick one of these in a vice and use a string to pull the trigger.



Aim it into a blowtorch flame or similar. Unless the valve on the can is gummed up so bad that it doesn't re-seal, I don't see anything that can go wrong (of course I'm probably underestimating a teenager's ability to discover something).

of course I'm probably underestimating a teenager's ability to discover something

like FLAME THROWER mwahahahahaha

I think that the testing bucket idea is very good, a safe way to ignite it would be using model rocket ignitions (the ones that you plug into a 9v battery). that way you could do it while being a long way away from the bucket. one thing i have been wondering is why none of the standard combustion use hydrogen as its gas?

one thing i have been wondering is why none of the standard combustion use hydrogen as its gas?

well its not like that stuff comes in small affordable quantity's (unlike propane or hair spray), and until you asked that question i didn't even know hydrogen was commercially available. do you use hydrogen for your launchers.

Hydrogen flame front prorogation is slightly faster than Acetylene. It is not recommended in any launcher that would break if you pounded on it with a hammer.

I found this online in reference to a flame rate in tubing.
"From the literature, the Butane rate is 60 ft/sec. Acetylene 330 ft/sec. Tank Hydrogen (H2) 680 ft/sec."

Basically it go boom.

Found here;
http://keelynet.com/energy/oxyhyd2.htm