AT J-350 question

[fireone]

I wa stold by a friend that these 38mm motors have been known to CATO more often than getting the rocket in the air.
I would like to ask those of you who have had both good and bad with these motors to let me know your feelings on this statement.

Thank you

John

 

[Ryan S.]

they would cato when they were made by Ellis in the humid air because bubbles formed in the propellant. The problem is solved now and the J350s are working fine as far as I know

 

[solrules]

ellis made J350's?

 

[Donaldsrockets]

Aerotech formed a business relationship after their big fire in October of 2001 that burned their motor manufacturing facilities to the ground.

Ellis did produce the J350W as well as some other Aerotech White Lightning and Blue Thunder reloads.

That was the J350W that was known to CATO at ignition. Aerotech has since corrected the problem.

I have not heard of any J350W failures recently except the one that supposedly set the ATF van on fire but that was an Ellis manufactured load.

 

[daveyfire]

Ahh Ellis J350s...

We called them Spongebob motors

 

[fireone]

Thank you for all your info, it makes me feel a little better knowing all that work I just did is not going to be confetti raining down on all of us. You guys are te best at getting answers quickly, keep up the great work here.

John

 

[firemanup]

I'm 5 for 5 so far this year on AT J350's.. no problems with the motors at all......

 

[DPatell]

I remember the Ellis J350's!

Had one CATO for my dad's L2 attempt at NYPower!

The J350's now are fine and as impressive as ever.

 

[Ryan S.]

Originally posted by daveyfire


We called them Spongebob motors

LOL, yeah bubbles and motors...BAD mix.

 

[Joe Burger]

Originally posted by daveyfire
Ahh Ellis J350s...

We called them Spongebob motors

ROTFLMAO! That is the first time I have heard that. That truly made me bust out laughing fairly hard.

Just for the record and in defense of Bob Ellis, the humidity he was dealing with in Texas was truly the problem and nothing Ellis Mountain did wrong.

Those motors are fine now as stated.

Still LMAO!

 

[UhClem]

Here is a dumb question for Joe:

During the "SpongeBob" J350 problem, Aerotech recertified the J350 using a larger core diameter. What is the configuration of the current production J350's?

TMT shows a certification expiration of June 2001 for the original configuration and 2005 for the large core. Which would imply that Aerotech cannot sell them in the original configuration as certified motors.

Or have they been recertified again?

 

[Ryan S.]

Originally posted by Joe Burger
ROTFLMAO! That is the first time I have heard that. That truly made me bust out laughing fairly hard.

Just for the record and in defense of Bob Ellis, the humidity he was dealing with in Texas was truly the problem and nothing Ellis Mountain did wrong.

Those motors are fine now as stated.

Still LMAO!

yeah one of those things you really cant help. That was a great name though, Halarious.

 

[Joe Burger]

Originally posted by UhClem
Here is a dumb question for Joe:

During the "SpongeBob" J350 problem, Aerotech recertified the J350 using a larger core diameter. What is the configuration of the current production J350's?

TMT shows a certification expiration of June 2001 for the original configuration and 2005 for the large core. Which would imply that Aerotech cannot sell them in the original configuration as certified motors.

Or have they been recertified again?

Not a dumb question at all...in fact an excellent question.

The current J350's being produced in Utah are at the larger core size. As you have stated, they were recertified to this configuration until 2005.

TMT has asked us if we would like to recertify the J350 with the original core size and we will probably approach that scenario as the current certification nears expiration.

The loads are working just fine as they are so we figure....why fix it if it ain't broke?

 

[daveyfire]

Originally posted by Joe Burger
ROTFLMAO! That is the first time I have heard that. That truly made me bust out laughing fairly hard.

Glad I could be of service

What binder/curative system did Bob switch to in order to alleviate the squishy problem (143L? PAPI?)? Or would I be shot if I knew? I think I'm having some moisture problems myself in propellant...

 

[Ryan S.]

try doing it an an AC room, it will take longer but it might be worth it

BTW I live in MA, pretty humid but 143L does the trick pretty well. I dont mean to cross the border here, but I dont think I said too much

 

[daveyfire]

I think as long as we don't post a "x% of curative and y% of binder" we'll be all right -- generalities are OK. We're talking polymer chemistry here!