BP E16 that fell: Tempting fate? Need an answer soon...

[ActingLikeAKid]

Had an Estes E16 fall maybe 2 feet onto hardwood.... I know there's been talk of a dropped motor leading to a CATO ... Is a fall like that "Don't worry about it" or "call it lost money and don't tempt fate"?


Your answer may make tomorrow's launch a better day.

 

[watermelonman]

Give it a launch lug and burn it nozzle up without a rocket.

Every time I burn a motor without flying a rocket I am surprised how entertaining it is!

 

[TopRamen]

I don't think I'de glue a launch lug to it or allow it to fly freely, but I would definitely static test it rather than use it in a rocket.


[video=youtube;h6UHCGY775c]https://www.youtube.com/watch?v=h6UHCGY775c[/video]

 

[Mr Rocket]

I don't think I'd glue a launch lug to it or allow it to fly freely, but I would definitely static test it rather than use it in a rocket.


+1

 

[watermelonman]

I think a lug would stay on fine. To be clear I mean that as a way to attach to a launch pad and fire inverted, not to try to fly the motor case by itself.

 

[TopRamen]

I think a lug would stay on fine. To be clear I mean that as a way to attach to a launch pad and fire inverted, not to try to fly the motor case by itself.

That is clever. Just make sure you use JB Weld and fiberglass cloth. Don't want it getting loose!!
Probably put something on the exposed portion of the rod to protect it from blast effects too would be good. Aluminum foil maybe?

And regular JB Weld, not JB Quick, as that gets really hot when it sets up.
Best not to let it get wrapped around a blackpowder motor, or any motor.

 

[jd2cylman]

That is clever. Just make sure you use JB Weld and fiberglass cloth. Don't want it getting loose!!
Probably put something on the exposed portion of the rod to protect it from blast effects too would be good. Aluminum foil maybe?

And regular JB Weld, not JB Quick, as that gets really hot when it sets up.
Best not to let it get wrapped around a blackpowder motor, or any motor.

Duct tape....

 

[midpower_madness]

Yes, I've seen a CATO will a very light fall with those larger Estes motors. The propellent grain can crack easily when you have a greater mass...

 

[AfterBurners]

Better call Saul

 

[Rex R]

easy test stand is bore an appropriate size hole(or a set of holes) into a 4 x 4.
Rex

 

[ActingLikeAKid]

Y'all are awesome. Buoyed by a GREAT first flight, I loaded up THE DANGER MOTOR and figured "what the heck..." I had my sons' Watchamacallits ready to go too. Got theirs loaded up and hooked up, got mine with the dangerous E ....and that launch rod was really sticky. I just wasn't sure that it was going to slide off well. And then I realized I'd forgot to put an igniter in. At that point I thought "OK, Rocket Gods, point made."
I have some 29mm motor mount tubing; I think I might try a 29mm minimum diameter scratch-built rocket. Just to see what happens.

 

[Bat-mite]

You might want to use a 30-foot launch controller, just in case.

 

[shreadvector]

I tested a full production lot of D12 motors and the only way to make them cato was to temperature cycle them and fire them 75 degrees colder than the highest temperature they had been cycled to or hit them VERY hard on the side with a hammer.

Dropping them onto concrete from several feet high did nothing.

Running them in a lapidary tumbler with porcelain pellets for hours and hours did nothing (beyond fraying the edges of the cardboard casing and dislodging the ejection charge and clay cap). They all fired fine.

 

[ActingLikeAKid]

I tested a full production lot of D12 motors and the only way to make them cato was to temperature cycle them and fire them 75 degrees colder than the highest temperature they had been cycled to or hit them VERY hard on the side with a hammer.

I thought I'd heard something like that. Well, in an abundance of caution, I left it out. Now I'm building a 29mm minimum diameter rocket quick & dirty just to launch it.

 

[Sooner Boomer]

I tested a full production lot of D12 motors...

How many in a full production run?

(and really, you know all that proved was that that run had no CATOs. any other lot might)

I remember when the D13s first came out...

 

[shreadvector]

Actually, it was not a full production run, which is why I said "lot", not "run". More precisely it was 432 motors which was either one or two cases (I know they were blister packed but I do not recall if they were shipped in one or two cardboard case boxes).

Production is pretty uniform, and I tested a bunch as controls at the beginning and end of the testing (temperature, humidity, physical abuse) and none of the control motors failed. In other words, dropping a motor from any one manufacturing day will not cause a malfunction - the day it was made has no effect on how it will respond to dropping.

Hitting any motor with a hammer will cause it to fail no matter what day it was manufactured.

How many in a full production run?

(and really, you know all that proved was that that run had no catos. any other lot might)

I remember when the D13s first came out...