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cwbullet

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When you assemble an a motor for use with electronic deployment, you still need a delay grain.

Without a delay, the motor becomes a bidirectional fireworks fountain.
 

jd2cylman

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Pictures?
Some lessons are more expensive than others...
 

cwbullet

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When I get home.
 

cwbullet

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That is pretty close. The sad thing is it happened to the same rocket twice in one weekend. This time it is gonna take a lot more repair work.
 

blackjack2564

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RMRG5003.jpg
poster92211698.jpg
Yup, been there done that.
J-90 long burn,in my original Wildman rocket,
Without the delay it REALLY burned a looooooooooong time. The pic was cropped from Rockets mag and made into the infamous poster!

I had the delay loaded and ready on table BUT was talking to someone and grabbed a empty closure and screwed it on...lol.......not paying attention.

Same thing Chuck?
 
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BDB

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When you assemble an a motor for use with electronic deployment, you still need a delay grain.

Without a delay, the motor becomes a bidirectional fireworks fountain.
Is this true even if you have a plugged forward bulkhead?

I’m pretty sure I’ve flown Loki 38 mm motors with a plugged forward closure with no delay. Maybe I’ve just gotten lucky....
 

dhbarr

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Same if you overdrill the delay, my Mustang went out that way.
 

Brent

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Did it happen yesterday too?
 

dr wogz

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Same can be said for CTI motors, when you forget to put the reload into the case (and just load the reload into the rocket) !!
 

djs

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Is this true even if you have a plugged forward bulkhead?

I’m pretty sure I’ve flown Loki 38 mm motors with a plugged forward closure with no delay. Maybe I’ve just gotten lucky....
Normally no- you wouldn't need this. However without a delay grain, you run the risk of putting the igniter in too far up and having trouble lighting the motor.
 
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