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Plastic nozzle cap question

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dshmel

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What is the purpose of putting the red plastic nozzle cap on the end of the nozzle? Is it to help build pressure in the motor or to just hold the igniter?
 

timbucktoo

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Me say to hold the igniter because I forget to put it on most of the time and I always use masking tape to hold the igniter in place.
 

dhbarr

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Perhaps it helps ensure the igniter is pulled straight out in one smooth motion? In addition to building pressure and ensuring the igniter doesn't slide.
 

jimzcatz

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To hold igniter. I believe somewhere in the instructions it say to cut a slit in it to relieve pressure.
 

scsager

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To hold the igniter in place.
 

djs

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It's for identifying when certain people (*ahem CZTeacherman*) are cheating in a drag race. He had a yellow cap, not a red one! And he wasn't flying a G53FJ, but an H163WT!

joke's on him though- after the rockets took off, we agreed that the winner of the race was "closest to the pad"
 

rstaff3

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I never use them for their intended purpose. But I do use the CTI equivalent. :flyingpig:
 

cerving

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Before you install the igniter, it's a dust cap to keep dirt out of the nozzle. You can use it for holding the igniter in, too... I've stopped using the Aerotech caps because it's easier to use masking tape to hold in the igniter rather than having to cut a vent in the cap. CTI caps already have a hole, so I still use those.
 

AdAstraPerAspera

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The Aerotech ones do a decent job keeping moisture out since they don't have a vent and fit nice and snug.
 

Larry Curcio

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Far as I can tell, they serve no purpose anymore. Time was, they were there to make Copperhead igniters fail.
 
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