K550 Minimum delay?

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EBurg

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Hey folks -
Working on a project that won't be easy to use electronics for deployment. Has anyone had luck drilling out a K550 down to a delay of <6 seconds? Ideally I'd like to get to 4 seconds. No problem using a drill bit to get there but wondering if there will be enough delay grain to hold in the pressure.

Thanks!
Eric
 
On the AT 29-54mm DMS Adjustable delay instructions 1.2 states caution: Do not shorten the time delay to a value less than 6 seconds.
My guess is it will either blow through, or that short of a delay is just a pretty good guess. As they all kind of are.
 
Huh! That's new to me, thanks for pointing to it

Thrustcurve says a 30 lb 12" rocket still needs 6.5s delay, but fails the rail exit check. I'm curios what this project is too
 
NFPA 1125 requires certification testing at minimum, maximum, and at least one intermediate time for motors that have adjustable delays. (8.1.8, 8.2.8) I wouldn't go below that minimum certified time.

As for what could require a 4 second delay, it will be something which has a lot of drag for its mass. A Tetrahedron of Extremely Painful Death or some such.
 
UhClem is right - it's not heavy, it's draggy..... I may have to find a way to add some electronics - I think 6 will be a bit long. Thanks for the info so far!
 
Huh! That's new to me, thanks for pointing to it

Thrustcurve says a 30 lb 12" rocket still needs 6.5s delay, but fails the rail exit check. I'm curios what this project is too
Hi Nyt, not a problem. I actually did not know the hobby line could get down to 4 seconds, so thanks for letting me know that. Dave.
 
I saw that also. I can't solder surface mount stuff but saw most was through hole on the Apogee one. Might have to try it.

I *think* that the barometric sensor comes already soldered the board, so that leaves only 1 SMT part (the cap) to solder for the Apogee. But yeah, that looks very appealing.
 
Who's flying J and K motors on motor eject?

There's a lot of not very aerodynamic rockets that don't go crazy high on a J and aren't so massive that you absolutely have to have redundancy. 4" LOC Goblin, Fiber Max, that sort of thing.
 
Yup, built a new launch pad that holds it vertical. Flight are now straight up AND down.
1st is of the first flight, pad would not that much weight off center.
 

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Hey folks -
Working on a project that won't be easy to use electronics for deployment. Has anyone had luck drilling out a K550 down to a delay of <6 seconds? Ideally I'd like to get to 4 seconds. No problem using a drill bit to get there but wondering if there will be enough delay grain to hold in the pressure.

Thanks!
Eric

Is there a gnome at the top of this rocket??? 🤪 🤪
 
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