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Stradivari
20th September 2010, 12:56 AM
I know black powder motors especially big ones have a tendency to go Ka-Boom if they have been temperature cycled or are really old. I have some single use E,F,and G motors and a few reloads that are about 9 or so years old. I am on my third go-round as a rocket dude. I stupidly lost my L1 and L2 when I was a bit short of funds and did not renew my NAR membership. No big thing, I have no problems playing by the rules, and I knew what they were at the time, I just got busy with work and with life and screwed the pooch. Are my motors and reloads any good? They have always been kept in an air conditioned house at the same conditions as my Violin and Viola (a lot more invested in that 500 grams of maple and spruce!) (not to mention bows) Are my vintage Dr. rocket hardware sets OK? or have they changed the things? My 38mm and 29mm sets have the metal seal rings. If the motors are no good I guess I can save them for static firing. I'm going to start a rocket club at school and it would be neat to fly My Lil' Nuke on an F for the kids.

Thanks Guys,

Dwight

cjl
20th September 2010, 01:20 AM
The motor casings are fine. As for the reloads? If they're still sealed, they're almost definitely good. Otherwise, as long as the humidity isn't too high, they're probably OK. High humidity can cause the grains to swell, so if they were opened and stored with humidity, I wouldn't fire them, but other than that, I wouldn't worry too much. I've used 10 year old motors without a problem.

MarkII
20th September 2010, 03:10 AM
Also, re: your comment about black powder motors, many people here have reported firing 40+ year old motors that have not been stored in any special way, except to prevent severe temperature cycling. And to be of concern, the temp cycling has to be pretty drastic and repeated.

G2Rockets
22nd September 2010, 02:42 AM
The motor casings are fine. As for the reloads? If they're still sealed, they're almost definitely good. Otherwise, as long as the humidity isn't too high, they're probably OK. High humidity can cause the grains to swell, so if they were opened and stored with humidity, I wouldn't fire them, but other than that, I wouldn't worry too much. I've used 10 year old motors without a problem.

Holy smokes Chris! 10 years? That's almost as old as you!:roll::D
Acutally I have some motors I believe are as old as you. They are only C's, but probably at least 15 to 20 years(thats close to your age I believe). I got them from a friend. I have been afraid to set them off in anything too nice. My youngest used an older motor in a cluster and it didn't ignite:confused2: Land Shark!!!:y:

John