Shelf life of BP motors?

[SPONGE]

I just got a box in the mail from my inlaws that has a lot of rather old looking Estes motors in it. I think they could be as old as 10 or 15 years. What can I expect from igniters and motors that old? Will they even light? Is there any greater risk of a cato? I haven't had a chance to look through everything, but there is a little of everything from 1/2As to D12s. I even found a B14. I hope these are OK to use. It would save me a lot of money. There is easily over $200 worth of motors here.

 

[rstaff3]

....ahhhh.....B14.......

It may depend on the storage conditions, but I think they are probably OK. The longest I had stored motors was ~9 years. I think I've heard of much longer periods, but have no references.

 

[Dogsbd]

I'd only worry about how they may have been handled roughly over the years, causing cracks in the nozzles, cracks/voids in the powder etc.

 

[jflis]

I have motors well over 20 years old that I use on occation. have had a couple of cato's, but not that many, and all could have been avoided had I used a little more common sense concerning nozzle condition.

If they look good, try a couple in models that aren't that important to you, to see if they are working.

Also, check the motors against the cert list if you are flying at NAR sanctioned club launches. The B14, for example, can't be flown as it is no longer contest nor safety certified (NAR insurance won't be in effect and the RSO should reject the motor on those grounds)

jim

 

[SPONGE]

Thanks for that tip, Jflis. I was going to fly it at a club launch this weekend. I'll have to save it for a day in the park. If our launch doesn't get scrubbed because of the weather, I'll fly some of the old motors and report back.

 

[Stones]

D12's and C6's that were purchased in the late 80's to 90...
everyone performed without flaw. They were kept at room temp and not handled much. I threw one B something out as the nozzle looked a bit cheezy.
Question... do composites hold up this well? I've read that AP can get difficult to ignite with time.

 

[Austin]

Stones,

A good friend, fellow L3'er and forum member Jim Scarpine just reacently had flown some old H, I and J loads he has had around for a good 10+ years and they lit every time, even with those extra large crapperheads...so I would say yes, as long as they remain in their sealed plastic bag, they would last a very long time. BTW, his were all Blue Thunder...so at least they hold up.

Carl

 

[SPONGE]

Well, I got to fire one of these old engines today before the rain started. I flew one of the B4-4s, and it worked perfectly. As a matter of fact, it worked better than a brand new B6-4 that did not fire it's ejection charge, sticking my brand new Baby Bertha in the mud. Sorry, no pics from today. The weather was on the edge and we were lucky to fire off the five flights we did get.

 

[kgholloway]

Carl,

Our local club here in Erie has been flying older motors for the last year due to the Aerotech situation. Many of them are 5+ years old. We've had no problems with Blue Thunder loads and only minor problems with White Lightning loads. The WL loads seem to be harder to ignite the older they are. The solution for this is to "rough up" the slot or core hole in the upper grain area where the ignitor is placed.

I have seen two CATO's that may have been due to the age of the WL grains involved. Both of the motors were assembled with 5+ year old grains but the RDK kits were brand new short delay elements. Both of the motors used Ignitorman ignitors but neither one had the upper grain roughed up to facilitate ignition. Both of the motors, upon depressing of the launch button, were observed to "chuff" and then to sit smoking on the pad for 3 to 4 seconds before the motor came up to pressure and the rocket lifted off. Both of these motors experienced forward closure "blow by" at approximately 200' feet AGL.

No one knows for sure but I believe that the new RDK kits ignited at the initial chuff and sat there burning for 3 to 4 seconds until the heat, ash, and combustion products eventually ignited the fuel grains. If this was the case then the delay column would have burned down to within one or two seconds of "burn through" before the motor came up to pressure resulting in the forward seal failing at power. As I mentioned previously the upper grains were not roughed up with sandpaper on these two motors. Older WL motors that were roughed up have not exhibited this possible failure mode to my knowledge.

Ken

 

[powderburner]

I have a gob of ancient stuff that is probably 30 years old. I have kept them indoors, air conditioned in summer and heated in winter, and dry year round. They have been working just great for me--- no blowouts, no catos (knock on wood), no failures of any sort. But now that you have put this thought into my head . . . .

 

[scm86]

ive used Estes motors that are older than i, im 15, and not one cato'd.

a friends mom's friends son went to college and didnt want them anymore so they were channeled to me, i got about 20 old motors and a few rockets. i static fired a bunch of them of them in the backyard, as i was told to do so by the people in ROL chat. i half expected them to blow up, but after awhile, i figured that they werent going to blow up. i flew them at the local (ok, maybe not quite local...) in rockets i really didnt care if they blew up, and got alot of great flights without a single cato, tho i used new ignitors, the old ones looked kinda crappy.

Scott McNeely

 

[aadamson]

I think the issues with the WL loads are the fact that they tend to oxidize. I've herd that if you just take a light sanding to them (don't create any heat), to knock off the oxidization, that they'll wook good as new. I've got some +5yr 29/40-120 reloads that seem to work just as good as new. However I'm not a fan of the F40's, I can't get the right performance out of them. They fly about like F22's

Alan

 

[mmkteaneck]

I got a bunch of Centuri B3's that came in an auction that I won. (I was really bidding on the other engines in the lot.) That's when they still used pounds, so they're really B14's.

I've used a couple of the B3-0's. The 1st lifted off so fast that it seemed to disappear! The only reason that I got the rocket back was that the 1st stage nearly hit me on the head, and someone found the top stage later. The snd flight lawn-darted: on an ejection failure of the NEW 2nd stage engine. The B3-0 worked great! There was also one flight where my sone put a "B3" into an Estes Mark II. Now I know the "speed of balsa"; shredded fins everywhere!

So, BP engines seem to have a LONG shelf life. I still have a bunch of B"3"-0's to have fun with!

 

[SPONGE]

I had a cato last weekend with one of the D12s from this batch. I was launching a scratch build 3x cluster and one of the forward bulkheads failed. It was very spectacular with a big ball of fire shooting out the top of the rocket. You can see the pic on my thread in the scratch built forum. Of the six old D12s I lit last weekend, only one failed