SpudFiles

has anyone tried using a graphite rod or even a light bulb in a circuit with a on /off switch to light their propellent in their hybrid/ combustible. It would work wouldn't it ?

It may work, but it'd be horribly inefficient. Graphite is a fairly good conductor, and tungsten reacts fairly readily in air. Reusable ignition sources are preferred, unless the situation does not permit (Activation energy too high for a spark).

A light globe would be a single use item, the filament would get broken after the first shot.

A graphite rod could work, if you used two with a fine contact point that would produce a lot of heat, I've tried a very crude weld with such a rod.

i believe what you are looking for is right here
http://www.wonderhowto.com/topic/make-a ... c-igniter/

Again, avoid consumable ignition sources. Look around at the advanced combustions and hybrids in the showcases.

a 9 v battery with some wire attached to a graphite rod heats up very quickly and turn glowing red hot in a matter of seconds, but would it withstand the combustion

Glow plugs from model airplane engines does the same thing. Ones with the "Idle Bar" do better in high compression engines with hot fuel mixes. It was designed to "withstand the combustion". They are good for more than one shot.

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At that temperature, isn't the graphite significantly oxidized?

also on ignitions ,in particular a spark plug .Where are the positive and negative terminals located ? I have tried googling it but turned up empty

in cars the out side is - and the middle terminal is high voltage + that cable need to be well insulated but the - can be just about anything.

so applying this information, a metal chamber itself could the "car" being negative or i can just solder a wire to it and the middle is a positive so just need to solder a wire and attach it to an ignition and we are good to go

by the way - would a piezo be able to make a spark going through / using a spark plug ?

I use a spark plug and a BBQ piezo igniter. Works well. Keep in mind that while any metal conducting part that touches your sparkplug body will do the job, the nearer you get, the beter. When you apply high voltage, it excites the particles of the metal you're dumping the voltage in. These "impacts" are a pure waste of energy for your use. Means that you lose energy.
So, as long as you don't get a 10 feet chamber and plug side to side, you're good to go.

sounds good , your confirmation is just what im looking for , but im a little indecisive about either insulating the spark plug or spark gap or just using the chamber to with the spark plug or gap

i think using a spark plug connected to the chamber will be easier because i could easily attach wires where needed and the other hand insulation would feel safer because everything is insulated but slightly harder to work with so yeah

Major Collins wrote:insulation would feel safer because everything is insulated but slightly harder to work with so yeah

Nearly every car on the road today uses an insulated positive side and common ground negative side electrical system with the chassis as the ground. Yes, even your spark plugs ground to the engine block. You don't get zapped every time you touch a bolt in your car while the engine is running, do you?