Old vs. New single use motors

[rocketsonly]

Hey, the Estes single use engines have expiration dates? Can any type of motors expire? My friend gave me a how box full of motors ranging from A's to C's. I'm using the motors for a science fair project. Do you all think the age will effect anything? I test fired one a couple motors today by taping them upside down on a launch rod and igniting them. Now that was fun! Gladly I didn't hurt myself.
-Matthew

 

[rocketsonly]

Oops, sorry, I forgot to say the engines are 5-8 years old.
-Matthew

 

[powderburner]

They should be just fine, as long as they were stored in a temperature- and humidity-controlled space.

I have been using motors that are waaaaay older than that, and they have all worked fine so far.

 

[vjp]

I've fired motors nearly 15 years old, just fine.

Others have fired motors over 25 years old.

As long as you never freeze them or put them in a really hot place (car left in sun all day, attic, etc.) they will probably last fifty years.

 

[Ryan S.]

I have also fired old motors, and if you tested some and they didnt blow up, chances are you are okay with the rest

 

[UhClem]

I used a number of older Estes motors a while back. They were about 20 to 25 years old and had spent 15 years stored in an enclosed but uninsulated, unheated, and unairconditioned patio in northern Oklahoma. So the motors were soaked to tempertures in excess of 100 degrees and below zero.

The only problem I had was with the C engines (all C6-0's) which had an annoying tendancy for the propellant to unbond from the case.

 

[scadaman29325]

It just so happened that this weekend one of the guys in the club was using some OLD Ds and Es on two seperate launches, the results were not good.

On the first attempt (I think parrallel Es), one of the motors jumped out the back end in a beautiful slow burning fire and twirled about 50' out to the side, Thank God they didn't come backwards into one of the motor boxes. The other motor fell to the ground and burned out. I thought it had split the rocket in two, but this guy builds them STRONG. Spectacular event!

The second attempt was pretty nice also, not quite as FLAMEboyant though. It just sat on the rod and burned like a campfire, no thrust at all.

Between those motors and bad igniters/launcher problems, I think he only got one or two rockets up all day long. We asked him to give us a class next month on launch prep. ;-)

 

[scadaman29325]

I just happened across this:


https://www.lunar.org/docs/LUNARclips/v10/v10n5/oldengines.shtml

 

[shreadvector]

Beware the "Poopy Clay" years. Really old is OK if stored properly. Semi-old could be "Poopy Clay". It's easy to tell.

Originally posted by rocketsonly
Hey, the Estes single use engines have expiration dates? Can any type of motors expire? My friend gave me a how box full of motors ranging from A's to C's. I'm using the motors for a science fair project. Do you all think the age will effect anything? I test fired one a couple motors today by taping them upside down on a launch rod and igniting them. Now that was fun! Gladly I didn't hurt myself.
-Matthew