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18 year old AeroTech J350W looks like a no go?

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PokerJones

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So I have 2 of these J350W's from '99 and I decided I would fly one this weekend. After opening the package I discovered one of the grains was stuck in the liner and had expanded on both ends and turned greenish, I have never seen this before. All of the other grains were individually sealed and look fine.

Not sure about flying this one, what do you guys think. I have flown a lot of old motors with no issue but this looks sketchy at best.

20170407_111740.jpg20170407_111742.jpg20170407_111756.jpg

I checked the other package and it looks the same. Maybe just combine the kits and use 6 good grains for a J350 and have a few left over.

20170407_114121.jpg
 

cavecentral

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I've heard people cut of the swelled ends and fly, but never tried it. Maybe someone that has can share their results.
 

3stoogesrocketry

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So I have 2 of these J350W's from '99 and I decided I would fly one this weekend. After opening the package I discovered one of the grains was stuck in the liner and had expanded on both ends and turned greenish, I have never seen this before. All of the other grains were individually sealed and look fine.

Not sure about flying this one, what do you guys think. I have flown a lot of old motors with no issue but this looks sketchy at best.

View attachment 316683View attachment 316684View attachment 316685

I checked the other package and it looks the same. Maybe just combine the kits and use 6 good grains for a J350 and have a few left over.

View attachment 316686
Trim the swollen grain flat and fly it.
 

Steve Shannon

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I would ask Aerotech customer service. I think they will say trim and fly, but they're the authoritative source.
 

Rocketjunkie

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Trim the swollen grain and put it at the nozzle end. Put the best looking grain at the top. The swollen grain will be almost impossible to light if you put it at the top.
 

DavidMcCann

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+1 to cut it and nozzle end. Make sure the core is the same size as other grains too. If not slowly drill it out
 

PokerJones

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Well that was an interesting waste of time but at least I learned something. Trimmed the grain down but they are all a little swollen and took a bit of force to get them into the liner, so much in fact that the brittle liner cracked wide open. Tried the other motor and that liner cracked as well. Looks like I'm down to using my NEW J350s.
 

ksaves2

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Trim the swollen grain and put it at the nozzle end. Put the best looking grain at the top. The swollen grain will be almost impossible to light if you put it at the top.
Ditto, Trim or sand and put it on the bottom. The erosive phenolic nozzles will give you some leeway. If you don't want to.............. Send them to me!!:wink: I'd have no reservation flying them. Kurt

Oooops, I should read to the end of the thread. I would have said if the swelling wasn't that much, sand the sides of the grains so they'd fit in the liner but too late. Unfortunate burnpile fodder unless
you buy the liners and try again. Last time I tried to buy from Rocketparts the liners were kinda steep. Kurt
 
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eggplant

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You can buy replacement liners from Aerotech here. $14 isn't a bad deal, depending on how sad it would make you to dispose of the grains in a bonfire.
 

markkoelsch

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How were you storing them? Do you live in a humid area?
 

PokerJones

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How were you storing them? Do you live in a humid area?
I have only had these motors about a year now so I can't say how they had been stored for the prior 17. At $25 each from a local club donation I'm not too upset about it, besides I got 2 free Copperheads out of the deal :lol:
 

Rob702Martinez

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I did my L2 on a 19 year old j350w I just cut the swollen ends off which was only 2 grains. I put those grains at the nozzle end and the nicer ones at the top for the igniter. Using a crazyjim igniter and a small piece of BT...took a good moment to light. Flew the other 4 out of that lot the same way. Still have one left and this was last year in June and another last month.

If you want, i will give you 26$ each and let you know if they worked :kill:
 

manixFan

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It's bothersome how folks don't read the thread and then post irrelevant comments. NONE of the grains fit the liners - the liners cracked when the other grains were inserted. There were not any 'good ones' left over.


Tony
 
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Rob702Martinez

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It's bothersome how folks don't read the thread and then post irrelevant comments. NONE of the grains fit the liners - the liners cracked when the other grains were inserted. There were not any 'good ones' left over.


Tony
It's bothersome that you can't trim a grain(s) to fit in a liner, then get mad for someone having success with it and sharing their success.

I think it's bothersome that you discourage open ideas, that someone Would have, in the same situation.

Who cares.
 

timbucktoo

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NONE of the grains fit the liners - the liners cracked when the other grains were inserted. There were not any 'good ones' left over.
Did you try peeling the glassine layer off the grains before inserting into liner? That usually works!
 

pyrobob

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Poker, remind me and I'll see if I can get you some liners on my next order and you can salvage the grains.
 

grouch

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I have peeled many a grain casing to fit a liner. Standard practice with humidity.
 
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