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ok, this might not work at all, but if it does, I think the possibilities would be really cool.
Imagine your favorite firewhip. Its all fueled up, but unlit. You drag it forwards, over your head, and at just that right moment pull your arm back forward for the perfect crack, and all of the sudden you've got a brilliant fireball appear out of nowhere in the darkness.
Cracking a whip gets the popper up to sonic speeds, so why should it be impossible to harness just a little bit of that energy into creating a spark to light the fuel cloud that gets blown off?
my initial thought was somehow attach the tip of a 'strike anywhere' match to the end of the popper, figuring that air resistance might be enough at those speeds to get the tip to ignight. I dont know if thats a realistic possibility, and I'm sure we can come up with a more consistent and reusable method.
What do you guys think?
Imagine your favorite firewhip. Its all fueled up, but unlit. You drag it forwards, over your head, and at just that right moment pull your arm back forward for the perfect crack, and all of the sudden you've got a brilliant fireball appear out of nowhere in the darkness.
Cracking a whip gets the popper up to sonic speeds, so why should it be impossible to harness just a little bit of that energy into creating a spark to light the fuel cloud that gets blown off?
my initial thought was somehow attach the tip of a 'strike anywhere' match to the end of the popper, figuring that air resistance might be enough at those speeds to get the tip to ignight. I dont know if thats a realistic possibility, and I'm sure we can come up with a more consistent and reusable method.
What do you guys think?
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Maryland
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Re: Crazy Idea
Mon, April 16, 2007 - 12:50 AMYou could thread a shielded pair down the length of the whip and attach one end to a piezo-electric spark emitter. -
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Re: Crazy Idea
Mon, April 16, 2007 - 12:11 PMSo you'd have a button on the handle that you could click to light the whip at any time, right?
I like the thought. What is availible to us in order to protect the wire from both the mechanical stress of cracking a whip, and the thermal stress of being on fire? -
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Re: Crazy Idea
Wed, April 18, 2007 - 5:36 PM
Consider a glow plug
www.hobby-lobby.com/glowplug.htm
the one in the middle can be charged and has a batter, you could probably heat it and just hold it to the base of the whip.
You could also crack your inlight whip at an already lit torch.
Andreas -
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Re: Crazy Idea
Mon, April 23, 2007 - 11:39 AMFlash cotton shooter works great for that..They make small ones you can place right on the tip of your finger all you have to do is shoot it into your vapor and the tip of the whip from the 1st crack and poof there is your magical fire ball out of nowhere..if your using white gas your going to find you need more than a spark to ignite it you need a flame so dout the glow plug will work ...
You could even mount the flash cotton shooter onto the whips handle and just hit the lash.
You can get the shooter from any online magic shop they run about 30 bucks.. I got mine from Daytona magic suplly
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Re: Crazy Idea
Tue, April 24, 2007 - 7:47 AMAndreas, have you ever *used* a glow plug to ignite petrol in an open atmospheric state? I mean, compressed in an engine with precision fuel/air mixes is one thing, but not open. Just saying....you sure it'll work? -
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Re: Crazy Idea
Tue, April 24, 2007 - 3:16 PMFule needs a flame or spark to ignite it. A glow plug is not a flame or spark its just VERY hot. It will boil whatever fule you are useing. You still need a spark to ignite it. My guess is that it would not work. -
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Re: Crazy Idea
Tue, April 24, 2007 - 5:25 PMTo start a combustion reaction, all you need is enough activation energy to get the reaction going, it doesn't neccessarily have to be an existing flame or spark. Thats how car cigarette lighters work, the current heats the coil up hot enough that it will light a cigarette. Ive never worked with glow plugs, but I bet it would get hot enough to light white gas.
wheather or not it would work in this particular application or not, I dont know, but I'd say its worth a try.
Maybe mounted near the handle, something where you light the whip on the back stroke, so the flame travels the length of the whip just before you crack it?
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Re: Crazy Idea
Tue, April 24, 2007 - 6:59 PMBallast, most things have an "autoignition" temperature. It's the break-over temp that gets the reaction started. The nice thing about sparks is that they're blazingly hot, despite being short lived.
Also, if glow plugs didn't work, the trucking industry would be a VERY different beast. Most diesel engines do not produce sparks, they use glows to start the reaction, then compression and ambient heat do the rest. -
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Re: Crazy Idea
Fri, April 27, 2007 - 11:29 PMYes indeed most things do have an autoignition temp. White gas is not one of them. You do need a spark or flame. Glow plugs work for diesel fule becouse it does have an autoignition point (about 500F).
This is why you can stick hot torches into fule. Not a good ideia and I dont suggenst doing it. But it can be done. -
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Re: Crazy Idea
Sat, April 28, 2007 - 2:39 AMI'm sorry, but there's nothing, chemically speaking, that's particularly special about white gas that it shouldn't also have an autoignition point. It may be obscenely high, or require a density of vapor that isn't normally available, but if it lights from a spark, it's got an a-i temperature....
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Re: Crazy Idea
Tue, April 24, 2007 - 7:11 PMYeah, I think I used the wrong term when I said glow plug. The thing I am referring to is basically a light bulb without glass, instead it has coiled wire that glows red hot from a AA battery. It would easily light the white gas.
For white gas the smallest spark will do it is very volatile, lamp oil not so much.
Andreas -
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Re: Crazy Idea
Tue, April 24, 2007 - 8:22 PMActually, Andreas, while that's true of liquid at room temp, the autoigition temperature of lamp oil seems to be lower than white gas. Specifically, torches that are used over and over (or for teaching fire breathing, et al) can get hot enough to flash ignite lamp oil as it's sprayed on the tool. Typically, the device must get much hotter to do the same to white. -
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Re: Crazy Idea
Wed, April 25, 2007 - 8:59 AMI used to understand the difference in terms of the flash point of the two fuels. White gas produces fumes that will flash at a lower temperature, while lamp oil has a higher flash point, so it needs to be a bit warmer (like on hot torches) to produce fumes that are as volotie. I know the definition of flash point is more complicated than this, but I'm pretty sure thats the gist of the difference. -
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Re: Crazy Idea
Wed, April 25, 2007 - 9:46 AMWell, if you want, here's a complete write-up on what flash point is:
nafaa.pbwiki.com/FlashPoint
But, in short, it's the temperature at which a volatile substance will start producing vapors that will ignite if in the presence of a flame.
White gas has a flash point below 0, so it's pretty much always producing vapors, and lamp oil is at about 200 degrees or more. So white gas is producing vapors while it's sitting in the can, or in a puddle on ice. Lamp oil needs to be heated a couple hundred degrees before it starts producing the vapors needed to light.
But Flash point is completely unrelated to autoignition temperature, and has only coincidental relation to vapor pressure (how fast the volatile gas disperses).
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Re: Crazy Idea
Mon, November 19, 2007 - 10:06 PMGlo plugs will not light it without touching the fuel, I make fire ball shooters with these, and this may be a better idea.
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