But when i did get a spark in between the screws it would not light. So far i have used Axe and Bod. How much fuel do i put in there? Like a .5 second squirt or like a 1 second 1/2 half squirt?
Ahh help please
Problems with mini
Ok I just attempted to make a mini combustion with the pill bottle and pen tube method. Except my piezo thingy does not click anymore.
But when i did get a spark in between the screws it would not light. So far i have used Axe and Bod. How much fuel do i put in there? Like a .5 second squirt or like a 1 second 1/2 half squirt?
Ahh help please
But when i did get a spark in between the screws it would not light. So far i have used Axe and Bod. How much fuel do i put in there? Like a .5 second squirt or like a 1 second 1/2 half squirt?
Ahh help please
The big rule of thumb on combustion fuel problems:
You got too much fuel
The big rule of thumb on mini combustions:
You always have too much fuel!
Put in the smalles spray you can, wave it forth and back a few times and then close it.
Experiment with the amount of times waving it.
OR use a syringe to measure out fuel.
You got too much fuel
The big rule of thumb on mini combustions:
You always have too much fuel!
Put in the smalles spray you can, wave it forth and back a few times and then close it.
Experiment with the amount of times waving it.
OR use a syringe to measure out fuel.
You can also use a long nosed lighter, take out the nozzle, fuel hose and the gas tank(including valev). Glue the nozzle in the barrel as close to the spark-gap 
, connect the rubbe hose from the long-nosed lichter to the lichter itself and the nozzle that is glued in your combustion chamber . This wil have a result that you can put the feul in more accurate.
GR.Tom
, connect the rubbe hose from the long-nosed lichter to the lichter itself and the nozzle that is glued in your combustion chamber . This wil have a result that you can put the feul in more accurate.GR.Tom
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jimmy101
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You can convert a standard disposable butane lighter to a more accurate metering system like this.
Even without a syringe, it'll work better than an un-mod'd lighter since you can get the small piece of tubing well up into the chamber.
One challenge with a mini is getting the fuel to mix well. Kind of hard to put a fan in a chamber that small. A couple of BBs can be added and then the chamber shaken to try to help mixing.
Another challenge with a mini is getting anywhere near a reasonable CB ratio. For 1/4" ID copper tubing as the barrel, and using a typical pill bottle that is what maybe 1"x2", you have a chamber volume of ~1.5 in<sup>3</sup>. For a 1:1 CB the barrel would have to be 30 inches long. A 6" barrel gives a CB of 5. The BIC pen body has an even smaller ID than 1/4" pipe so a BIC barrel would need to be even longer. A grossly too large chamber (CB too big) will significantly drop the performance of a gun.
The size of the spark doesn't make any difference, small spark, big spark, are all the same.
Even without a syringe, it'll work better than an un-mod'd lighter since you can get the small piece of tubing well up into the chamber.
One challenge with a mini is getting the fuel to mix well. Kind of hard to put a fan in a chamber that small. A couple of BBs can be added and then the chamber shaken to try to help mixing.
Another challenge with a mini is getting anywhere near a reasonable CB ratio. For 1/4" ID copper tubing as the barrel, and using a typical pill bottle that is what maybe 1"x2", you have a chamber volume of ~1.5 in<sup>3</sup>. For a 1:1 CB the barrel would have to be 30 inches long. A 6" barrel gives a CB of 5. The BIC pen body has an even smaller ID than 1/4" pipe so a BIC barrel would need to be even longer. A grossly too large chamber (CB too big) will significantly drop the performance of a gun.
The size of the spark doesn't make any difference, small spark, big spark, are all the same.
