The Estes Igniter
An igniter is a device used to ignite a rocket engine. In Estes rocketry,
an igniter element is a strip of resistance wire with a coating of
pyrotechnic material on it. In the system it performs like a resistor
in an electrical circuit. As electricity passes through micro-clips
connected to the igniter, the igniter begins to glow and give off heat.
The pyrotechnic material coating is ignited and is the last step in the
ignition. Igniters must be installed so that the coating is touching the
dark-colored propellant grain. If the igniter is not touching the grain,
this could cause a misfire.

Heat created by the igniter is not great enough to cross a gap between
the igniter and propellant grain -- there must be direct contact between
the igniter and the propellant. First, separate the igniter you are going
to use from the other igniters by tearing or cutting the paper between any
two igniters. Do not remove the paper from the igniter as this may result
in cracking the pyrotechnic coating. Now take the igniter and insert it all
the way into the nozzle of the engine, making sure that the igniter is
touching the propellant grain. For some engines you may have to push the
igniter a long way down, as when using a C5 type engine, so push down gently
until the igniter will go no further. Make certain that the igniter’s leads
are not crossed. If the leads are crossed, this can cause a “short” in your
launch system and thus a misfire. Place the igniter plug in the nozzle of
the engine and press down firmly. Bend the igniter leads as shown to the below.
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