Bulge in a 29/240 case

I flew an H250 in my 29/240 case a week or so back, and when cleaning the case I noticed a very slight bulge (maybe 1/16 of an inch) that affects approximately 1/3 of the diameter of the case. It is hard to see, however, when laying the case on a table you can see it and ‘rock’ the case on the bulge.


What is more surprising is the location of this. I thought that it would have been at the end of the closure, however, as the picture shows, it is about 3/4 of an inch prior to the closure, which is an area that should be protected by the liner.

question - replace or fly as is? I am thinking that a wrap or two of tape on the liner should take care of this allowing me to fly.

thoughts?

Definitely don't fly it.... it's going to be a weak spot in the case.

Theory said:

I flew an H250 in my 29/240 case a week or so back, and when cleaning the case I noticed a very slight bulge (maybe 1/16 of an inch) that affects approximately 1/3 of the diameter of the case. It is hard to see, however, when laying the case on a table you can see it and ‘rock’ the case on the bulge.
View attachment 399083 View attachment 399084 View attachment 399085 View attachment 399086

What is more surprising is the location of this. I thought that it would have been at the end of the closure, however, as the picture shows, it is about 3/4 of an inch prior to the closure, which is an area that should be protected by the liner.

question - replace or fly as is? I am thinking that a wrap or two of tape on the liner should take care of this allowing me to fly.

thoughts?

Click to expand...

I'm not an expert, but I think that bulge represents a weak spot... I don't think I'd fly it in my best rocket.

Hey Theory;

I had an H250 blow out a 29-240 case a few years back. Spectacular CATO but a bad ending. I think the motor you flew was just short of that failure. Good catch on the bulge. Don't fly it, replace it. Take a good look at the seal disc as well.

Jim

rodger that

going to buy a new case

Theory said:

rodger that

going to buy a new case

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Before you do that- see if you can file a warranty claim with AT. Even though the motor didn't go bang, obviously something was off-nominal.

will do

curious if you think a casing with a date of 11/96 will be covered

Worth asking

agreed and done

I will let you all know what they say. Either way I will not fly it

Theory said:

will do

curious if you think a casing with a date of 11/96 will be covered

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It wasn’t the fault of the case, but possibly the reload. That’s what you should seek warranty service for and for the case that was damaged by it. And file a MESS report.

Hey Theory;

When mine blew, AT replaced the reload, the seal disc, and the casing tube. The casing and seal disc had awesome looking holes melted through them. The forward closure had lost a little anodizing, but I'm still flying those closures today. Warranty replacement would definitely be worth checking on. It's not a clear cut, cause and effect, deal as the casing is still with us. I have found AT to be pretty reasonable about warranty, so I would definitely talk to them and see what they have to say. In my case, it was a Dr. Rocket casing, so I was surprised when they replaced it. I hated to lose that casing, it was the first high power casing that I owned, I got my L1 with it. Dr. Rocket stuff is getting scarcer all the time as well.

Jim

Rodger that and I have reached out, and Steve, I will also file a report.

I really hope this isnt a systemic issue with the H250 load as I have another in my range box, and hope to fly more in the future. Very peppy off the pad...

Just got this back from Aerotech:

Hi Sean,



You can still use the casing, just remember to position the bulge towards the nozzle.

More than likely there was movement in the propellant stack that unseated the seal

disc, allowing the hot gasses to breach a portion of the O-ring. If and when you have

another issue with the casing, don’t hesitate to contact me.



Best,



Karl Baumann

Warranty and Tech.

Aerotech/Quest


Given that a new case is $55, I am going to buy one. Not sure how much I have in my Caliber ISP build, but the time alone is worth a lot more than $55!!!!!!!!!!!!!

Theory said:

Just got this back from Aerotech:
Hey Theory;


Hi Sean,



You can still use the casing, just remember to position the bulge towards the nozzle.

More than likely there was movement in the propellant stack that unseated the seal

disc, allowing the hot gasses to breach a portion of the O-ring. If and when you have

another issue with the casing, don’t hesitate to contact me.



Best,



Karl Baumann

Warranty and Tech.

Aerotech/Quest


Given that a new case is $55, I am going to buy one. Not sure how much I have in my Caliber ISP build, but the time alone is worth a lot more than $55!!!!!!!!!!!!!

Click to expand...

Hey Theory;

I jacked up my previous post, bad work on my part. It looked like I was trying to alter your original post. Sorry about that, I believe that I have it edited out. Buy Rocket Motors is a pretty good source for 29mm cases.

Jim-

My experiences with Karl are the same as yours Jim, honestly, nothing bad to say.

In this instance, I do not agree with his recommendation, and I do not have a project that I feel comfortable rolling the dice on. That said I will hang on to the case and mark it as you suggested.

I am a big fan of the peppy loads and flew a bunch of H220's prior to this H250; as such, an order has been placed for a new case.

The date code from the motor in question

To provide as much info as possible

Theory said:

The date code from the motor in question View attachment 399104

To provide as much info as possible

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Good work Theory. I am a big fan of the peppier 29/240 loads as well. Do the threads on the bulged casing feel normal? Threads are frequently a failure point on pressurized containers. Did you notice anything unusual about the flight? I really like the H250 and I use them frequently, but I'm a little paranoid about them as well.

Jim

Nothin different at all. Threads are in great shape. The burn on the motor was great. Actually left the pad so fast I had trouble keeping it in frame. Crazy for a 5.5” airframe

Theory said:

Nothin different at all. Threads are in great shape. The burn on the motor was great. Actually left the pad so fast I had trouble keeping it in frame. Crazy for a 5.5” airframe

View attachment 399119

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Nice shot. Looks like an awesome flight. You gotta love the H 250.

Jim