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no delay, no tracking smoke

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kramer714

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I want to have a motor with no delay (easy), and no tracking smoke (harder?). I'm working around a 29-60 motor case with a F62T reload. I'm using a plugged end and was thinking of doing either;

A) just leave out the delay
B) fill the area where the delay normally is with silicone rubber (o ring material)
c) Machining an aluminum plug that I will O ring in place

Any thoughts? Im leaning to A or B
 

MarkM

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I want to have a motor with no delay (easy), and no tracking smoke (harder?). I'm working around a 29-60 motor case with a F62T reload. I'm using a plugged end and was thinking of doing either;

A) just leave out the delay
B) fill the area where the delay normally is with silicone rubber (o ring material)
c) Machining an aluminum plug that I will O ring in place

Any thoughts? Im leaning to A or B
Neither. You can't fly it at a sanctioned TRA or NAR launch if you do. Doing either A or B is modifying the motor and rendering it uncertified. The motor was certified WITH the delay and hence must be flown with it. You don't need to put in an ejection charge, but must use the delay. A uncertified motor cannot be flown at a sanctioned TRA or NAR launch.

And C can't be done either for the very same reason.
 

MarkM

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is it 'legal' to change the delay time?

http://www.aerotech-rocketry.com/cu...tions/RDK_Instructions/rms_delay_mod_inst.pdf

How short of a delay = no delay?
Yes you can shorten the delay but you cannot remove the delay entirely.
Removing the delay entirely creates a volume void. With the delay removed the motor will operate at a different pressure and will not have the same burn parameters. Hence, you have modified the motor.

Shortening the delay does not create this same void since the delay element is still present. The shortest delay sold for the F62T is a "short" delay, which I think is 4 seconds. I would, therefore. guess that this is shortest you could "legally" fly it with.
 

hognutz63

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Just coat both of the ends of the delay grain with grease.

Why no tracking smoke?
 
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blackjack2564

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Very simple...just fill a delay insulator with epoxy. now you have an inert delay. Works just like the smoke ones. Can be used in plugged or ejection closure.

Use just like the real delay was in it, with the appropriate o-rings and seals. I have made several for 38mm and 54mm when I fly clusters. Saving the delays for use later. Why waste them on cluster flights..
 

cjl

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Easiest way: Thoroughly grease or even add a thin layer of epoxy to the side of the delay grain facing the propellant. It should not ignite, and your goal should be achieved. Why do you need a lack of tracking smoke though?
 

stickershock23

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Neither. You can't fly it at a sanctioned TRA or NAR launch if you do. Doing either A or B is modifying the motor and rendering it uncertified. The motor was certified WITH the delay and hence must be flown with it. You don't need to put in an ejection charge, but must use the delay. A uncertified motor cannot be flown at a sanctioned TRA or NAR launch.

And C can't be done either for the very same reason.
True you cant fly it at a sanctioned launch but he didnt ask if he could fly it he asked if it could be done.

I have cut a piece of proper diameter dowel and used it in place of delay grains before, works rather well.
 

kramer714

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im using the rocket to pull a parachute and didn't want to get the tracking smoke all over....
 
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