SpudFiles

Gasoline is used in cars for the large amount of gases they give off. But would it be safe for use in a combustion gun? If atomized I believe it could be. The only problem would be the large amount of heat given off.

Gotta be some less stinky alternatives that would give as much power. How about Heet gas line anti freeze, 99% Methanol, or starting fluid.

gasoline should burn clean as long as u atomize it pretty good like u said, i've used a spray bottle to prime a 3 wheeler engine before. a chamber fan would help i would think. as for the heat i dont think that would be a problem.

well, another factor would be economy. the 1 gallon for less than 4 dollars would guaranteed cost less than any other fluid. Not to mention the huge amount of shots you can get with that gasoline.

Heat is EXACTLY the thing you want.
Heat = pressure.
Pressure = force
Force = acceleration
Acceleration = Flying spud.

Propane gives off about the same heat as gasoline, dont bother about that.
Also, the heat lasts very short, the combusted gases in a cannon are cooled down within a second.
And because of the heat capacity of air (and generally all gases due to their low density) is so low, the amount of thermal energy isnt large enough to melt PVC. When the air in the chamber is like hundreds of degrees C and gives off all that energy to the chamber walls, the chamber walls temperature rises no more then just a few degrees. (Have to run a calculation on that one, it may be more or even way less, but you get the point)

The only problem is to get it atomized.

Any spray bottle could atomize gasoline. So gasoline would make good fuel.

gas has been used in combustions since they started. Its not really that dangerous and it works quite well.

It's not quite as powerful overall as propane, and would be more difficult to meter and mix properly, as it's a liquid at room temperature. If these challenges could be overcome, however, it could make for a very economical fuel.

Skim off some of the fumes hat accumulate in a sealed container.

Why go to the trouble of having to atomize or carburate gasoline for your spud gun when propane is a clean, cheap, easy to meter, more powerful, ready to go fuel?

0.12ml per liter of chamber volume is needed for proper mix.

Nothing wrong with gasoline as a fuel, other than practicality. Like others have said, the energy content per unit chamber volume is essentially identical to propane. The peak temperature and pressure aren't much different than any other hydrocarbon fuel. Heck, propane and gasoline are so interchangeable that most gasoline engines can be run on propane with only minimal modifications.

Benstern posted what is probably the most important limitation of gasoline as a spud gun fuel. 0.18ml/100in^3 of chamber. A drop from a "typical" eye dropper is about 0.1ml. Since gasoline evaporates so quickly it is pretty hard to get it to even stay in an eyedropper.

Getting the gas to evaporate isn't all that hard if you have a chamber fan.


Hmmm, an automotive fuel injector, high pressure pump, small reservoir of gasoline, 12V power supply ...

I had some white gas (camping fuel) in a spray bottle and I had intended to try it out with my PC. From what I understand, white gas is basically pure gasoline.

Anyway, long story short, the damn stuff dissolved part of the spray bottle - I guess there were some parts inside the spray pump thingie that are soluble in gasoline...

jimmy101 wrote:.....Hmmm, an automotive fuel injector, high pressure pump, small reservoir of gasoline, 12V power supply ...

Using fuel injectors has been on the super double secret probation drawing boards here at Starfire.... for propane though. Just have to get one and play with it some...don't think you would need as fancy an electronic control that's required in a car engine...activate for the right time is all. They are in the neighborhood of $60-100 depending on the model.

starman wrote: Using fuel injectors has been on the super double secret probation drawing boards here at Starfire.... for propane though. Just have to get one and play with it some...don't think you would need as fancy an electronic control that's required in a car engine...activate for the right time is all. They are in the neighborhood of $60-100 depending on the model.

Ya, for electronic control a 555 timer would work great, or just a pushbutton switch though the reproducability would suck with a pushbutton.

I wonder if you can get the injector and pump off a junked car?
I wonder if it should be a direct injector or an indirect injector (on the car)?