AT 29/40-120 Failure

Try using dow 111 it seals and lubes

one thing not mentioned here, is how was the delay grain entered. If it was inserted backwards, with the spacer facing the ejection well, then it may not seal properly against the Delay o ring. The spacer should always face the propellant. I have heard of this type of failure, when assembled like this.

That being said, should someone need it. I have a spare forward closure/delay well for the 29/40-120, as I had a rear closure failure with mine.

Delay grain was definitely forward... I could see a toasted remnant of the spacer ring inside the sleeve after I disassembled the motor.

I'll look into Dow 111.

crossfire said:

I can't believe plugging the charge hole would a problem. So if one wraps tape around the delay grain or peels paper off a motor grain isn't that making changes to a certified motor? I don't think so. No need to make a problem out of nothing.

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The catch to this is that AT instructions specifically tell you to wrap tape and peel paper, if needed, in the instructions. The JB weld is only designated for the 18/20 case at this time. If we can get an AT confirmation on using it with other cases, it could bypass this issue when using an ejection system that does not utilize the motor eject.

Can we all just join TRA and never have this stupid argument again?

DavidMcCann said:

Can we all just join TRA and never have this stupid argument again?

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I'm a member of both, I probably fly more TRA launches than NAR. You have to use manufacturer-certified motors at TRA launches too, unless you fly EX. It's what constitutes the certification that's in question.

DavidMcCann said:

Can we all just join TRA and never have this stupid argument again?

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In any event, only TRA L2/L3 members can fly EX. L0/L1s are still restricted to using only certified motors.

Former TRA 3562