How Long Do Engines Stay Good?

[RocketDad]

My daughter and I have some Estes D12-5 engines that are about a year old and we want to use them for a science fair project next month. We needed to purchase a few more of the same engines to complete the testing next month.

If the engines are a year old, and have been in the hot and humid garage here in South Florida, will they perform differently from the new engines purchased last week? The old ones are still in the original packaging, but I would not consider that such great protection as the packaging is a plastic front and cardboard backing. I'm sure the humidity got to them through the cardboard.

Thanks.

Rocket Dad

 

[RoyAtl]

The short answer is that, if they are visually OK (no difference from a fresh pack of motors), and you don't try to fly them on a day that's 50 degrees or below (doubtful in South Fla), they should be OK.

If the casing shows any water or humidity-sweat damage, or the nozzle looks rough and crumbly, I wouldn't use them in a rocket you're fond of.

Most motor failures are due to exposure to temperature extremes (a range of 50-75F or more) and/or operation at a temperature 50 degrees F colder than the maximum sustained temp exposure. Some motor failures occur due to manufacturing defects (which you probably couldn't be able to tell in advance).

 

[JoeLaunchman]

I bought a pack of D12-0's in 1995: used one in 1995, the other two in 2009. No problems after spending most of that time in a closed metal box.

 

[RocketDad]

I bought a pack of D12-0's in 1995: used one in 1995, the other two in 2009. No problems after spending most of that time in a closed metal box.

Wow! 14 years! Thanks.

 

[NjCo]

The main reason I'm a BAR for the 2nd time around is I found a box of old rockets and motors at my parents house most of which were from when I was a kid. I wanted to do a little test so I launched a half dozen of them from different packages and they all worked beautifully. One of them had a date on it from 1976 but it may have been several years older than that. Based on the packaging about a third of them were from the mid 70's or so and the rest were from the late 80s to early 90s. They were always kept in a dry basement at a fairly constant temperature. There were no visible signs of deterioration.

 

[billspad]

My daughter and I have some Estes D12-5 engines that are about a year old and we want to use them for a science fair project next month. We needed to purchase a few more of the same engines to complete the testing next month.

If the engines are a year old, and have been in the hot and humid garage here in South Florida, will they perform differently from the new engines purchased last week? The old ones are still in the original packaging, but I would not consider that such great protection as the packaging is a plastic front and cardboard backing. I'm sure the humidity got to them through the cardboard.

Thanks.

Rocket Dad

The engines will most likely perform properly but for the purposes of a science fair project you may want to get all the engines from the same lot.

 

[BobH48]

The last couple of years, I have been flying OOP motors as part of the old motor test program and flew a bunch that were made between 1969 and 1972. They were stored in a cardboard box on a closet shelf all those years. These were the ones that came in the blue mailing tubes or the diamond packs.

The only catos I've had with those motors were ones that were questionable when new (think Estes D13's here).

A few had weak ejection charges but for the most part they performed well.

I got a bunch of A10-0T boosters (new old stock in the red or green blister packs) that are less reliable but I don't know how they were stored.

About 60% work the way they should and most of the rest burn through instantly and ignite the sustainer motor at a very low altitude, sometimes while still on the rod. I had one cato and blow the booster of my Midget in pieces.

I also got a hold of some 1/2A3-0T and A3-0T boosters and every one of those performed flawlessly.

 

[ROCKet STAR]

I have a few estes motors that I have had for at least 15 or 16 years. I last used one of them when they were about 14 years old and it performed as well as anything I had bought recently.

 

[als57]

For black powder motors - storage conditions seem to be the key. Thermocycling the motor can cause cracks in the BP which can cause a failure/CATO. AP motors seem to be more resistant to this failure mode.

I just burned a 10+ year old H128W last weekend. Performed like it was made in 2009 ; not 1999.

Al

 

[cobra1336]

Mine last about 3 - 6 seconds

 

[powderburner]

(I don't think you understand how hard it is for me to post anything without making a joke like: "Generally, they stay good until their teenage years when they begin sleeping all day, hanging out in pool halls, running in gangs, and skipping school" so I hope you appreciate that I have stifled myself....sort of.)

I have a pretty good pile of motors left over from the 70s and 80s (a few date back to the late 60s) that I have been careful to store indoors. I have usually kept them in the back of a closet or something. Point is, they have not been "thermally cycled" by the summer heat and winter freezes. They have had pretty stable humidity and have not been banged up or knocked around. I use them pretty slowly because some of them are kinda goofy thrust levels (not much need for an 18mm 1/4A motor in any of my rockets any more) or borderline time delays (an upper stage motor with seven seconds is a looooong time for a single-stage, low-power rocket). So far, I have not had one failure. They continue to work just fine.

 

[dedleytedley]

I got an old Estes E motor as an unexpected bonus with some built rockets won on E-bay. The lot included four D-12s and an AT E-15:eyepop:. What a nice bonus! All the motors worked fine except for the Estes E. It exploded out the top and bottom at ignition with a loud bang gutting the interior of a large scratch-built. I'm guessing the motors were at least fifteen years old. Ted

 

[shreadvector]

I got an old Estes E motor as an unexpected bonus with some built rockets won on E-bay. The lot included four D-12s and an AT E-15:eyepop:. What a nice bonus! All the motors worked fine except for the Estes E. It exploded out the top and bottom at ignition with a loud bang gutting the interior of a large scratch-built. I'm guessing the motors were at least fifteen years old. Ted

Estes E15 motors were recalled and decertified due to their much higher than acceptable cato rate. They seemed to fail after aging a bit - wihtout any temperature cycling - and this was a result of the design and manufacturing method/materials. Thye spent a LOT of time designing and testing the E9 motor that eventually replaced it. it does not have the problems of the Estes E15 but it has a lower thrust level over a longer time.

 

[Micromeister]

Like bob48 I've also been buring a lot of OOP motors as part of the BP motor test program. but have never stopped using Old BP motors from the 60 and 70's.

Heat cycling is the only real killer of BP motors. You'll hear other stuff about HUMITIDY or dropping but with the exception of heat cycling they have not proven to pose any problem for BP motors manufactured as far back as 1963.

Experiments have shown that at least with D12s cycling the motors more the 70° seem to cause catos. I've been trying to use this same method to heat cycle Micro Maxx motors but as yet it hasn't worked. I'm sure Shreadvector has more detailed info he can pass on about those tests.



A couple things I personally try to do when purchasing Estes type 13, 18 and 24mm BP motors:
*Buy in the cooler months (spring, winter or fall). From a vendor I know buys the same way or directly from the motor manufactureer. This helps me know the motors I'm purchasing haven't been sitting around in a Freight trailer somewhere a couple weeks where the temp in that container can easily exceed 145°F.

* Try to say away from motors from big box type stores, Wal-mart, K-mart and such. same reasoning as above.

* for ecomomy try to purchase in larger quantities directly from the manufacturer or a trusted LOCAL hobby shop to get the freshest inventroy, and best pricing.

 

[Luv2launch]

When I became a BAR I used up my supply of motors that I bought when I was younger that were from the late 80's and all flew as intended.They were store in my basement which always holds pretty much the same tempurature and low humidity all year long.

 

[shrox]

I don't think high temperature exposure is that big a deal. Warehouses in Arizona routinely break 90 degrees, and people's storage sheds can easily get to 125.

 

[Luv2launch]

But high temp low temp combinations can affect motors.Maybe not so much AP but BP motors don't like getting cold then getting warm/hot too much.

 

[stickershock23]

I ended up with some reloads that were 15+ years old. I changed the delays, just to be sure. and they have all flown just fine!

 

[RocketFeller]

I flew an H238T reload last Friday that I had sitting in an ammo box since October 2000. It performed normally as far as I could tell. I did have an old Estes C6-0 booster motor that went cato and destroyed my Sam-X a few years ago.

 

[Johnly]

I've burned 12 year old composite motors on a test stand and have flown 25 year old well stored BP motors without a problem. Unless your BP motors have endured some rough storage, they should be just fine.

John

 

[accooper]

This past weekend I just launched a rocket designed by my son with a Estes B14-5! Made in 1969! With No problems. I have three of those left. We also launched rockets with A8-5's that where made in 1973!

It all depends on how they are stored on their life span. When I buy engines I take them out of the package and put them in zip lock freezer bags and press out as much air as I can. Here in San Antonio the humidity can reach 70% or more and this is not good for Black Powder.

Most CATOs I see with Estes engines are case or nozzle failures not failure to ignite. Lucky me I have never had a CATO.

Andrew From Texas

 

[harsas]

Just an additional perspective from someone also living in South Florida. I received a box of motors from an individual who stored them in a shed under his house. The never got wet, but were exposed to the humidity for abour 4 or 5 years. No major temp cycling. At least 30% of these motors failed. Primarily blown nozzles. Often the nozzle comes out in one piece and can be found laying in the ground. There is no visible difference between these motors and any others in my box.

Personally, I would have no problem with year old motors, but humidity definitely plays a role.

 

[ssaner]

Well, like a number of other posters, I had some motors left over from when I was a kid. I tried using a couple of them probably 18-20 years later. My experience was that on every one that I tried the ejection charge did not go off and I lost a couple of my old rockets. To my knowledge the motors were never exposed to moisture or extreme temperatures. These were Estes B and C type motors. I decided to destroy the rest of them as not being worth the risk.

That said, I wouldn't worry to much about a year old motor.

Steve

 

[shreadvector]

Well, like a number of other posters, I had some motors left over from when I was a kid. I tried using a couple of them probably 18-20 years later. My experience was that on every one that I tried the ejection charge did not go off and I lost a couple of my old rockets. To my knowledge the motors were never exposed to moisture or extreme temperatures. These were Estes B and C type motors. I decided to destroy the rest of them as not being worth the risk.

That said, I wouldn't worry to much about a year old motor.

Steve

If they were the very, very old type with the paper cap that retained the very finely powdered ejection charge, that would explain the ejection charge failures. The caps can easily leak and the powder disappears over time. And the power is exposed to air and can undergo a slow metamorphosis into something that does not go 'bang'.

 

[bobkrech]

Just an additional perspective from someone also living in South Florida. I received a box of motors from an individual who stored them in a shed under his house. The never got wet, but were exposed to the humidity for abour 4 or 5 years. No major temp cycling. At least 30% of these motors failed. Primarily blown nozzles. Often the nozzle comes out in one piece and can be found laying in the ground. There is no visible difference between these motors and any others in my box.

Personally, I would have no problem with year old motors, but humidity definitely plays a role.

BP motors stored under high humidiy conditions can absorb water. If you put motors in a sealed baggie in a warm car, you will sometimes find condensation inside the baggie, indicating that the motors have water in them. If you don't get the water out before you fire the motor the steam generated from combustion heat will produce additional pressure in the motor casing and possibly blow the nozzle.

I believe that if you put these motors out in the sun for a few hours or so you will drive the water out of the BP. If you then store the motors in a sealed bag or tin can with some indicating silica gel, the motors should stay dry. Indicating silica gel is bright blue when good and dull light purple when spent, so as long as the silica gell is blue, your motors are dry. You can regenerate spent silica gell by putting it on a cookie pan in an oven at 250 F for a few hours, but never put motors in the oven.

Bob

 

[tibadoe]

I have a few boxes of A-C size motors that are 15+ years old. I will let you know how they work in a few weeks. I did fire some of them off last year from the same batch and they did fine. They were stored in the basement.

 

[Initiator001]

snip

never put motors in the oven.

Bob

"Calling Trip Barber. Your wife wants to ask you what happened to the toaster oven..."

 

[Micromeister]

while I don't and never have kept my motors in Air tight containers, I do keep them in the house under climate controlled conditions. Humidity could be a contributor as bob mentioned but I find that it's the HIGH to LOW temp ignition spread that make the biggest difference in potential cato consideration...NOT the age of the motor. I have no fear whatever flying motors I purchased in the 60's. I do cut an X in the top clay of these old motors as that clap cap really gets hard. and as Shread mentioned check closely any with paper caps to be sure there is still powered in their.

As many have already posted southwesten state warehouses, Tractor Trailler storage, and personal sheds can all hit 90-125°f in the summer. storing motor in those conditions if you subtract 70°f the potential Cato range is somewhere between 20-55°f. Storing your motors where the ambient temp stays in the 70's takes that potential to near 0°f IF you can be sure your motors haven't spent any time at higher temps. This is why I try to purchase direct for from a rep that buys fresh stock several times a year. I try to make my bulk motor purchases in the late fall, winter or early spring.

At that I've still had a Cato or two. Over 40 some years only a handful but when they occur they are usually very interesting
Hope this helps.

 

[RimfireJim]

It all depends on how they are stored on their life span. When I buy engines I take them out of the package and put them in zip lock freezer bags and press out as much air as I can. Here in San Antonio the humidity can reach 70% or more and this is not good for Black Powder.

Unless you put desiccant inside the bags with the engines, and regenerate it as needed, I doubt your repackaging efforts make much difference. Plastic bags, even the thicker freezer type, aren't all that impermeable, so the humidity inside them will equilibrate with that outside of them eventually. This is the same reason wood finishes, such as polyurethane, can't keep wood from expanding and contracting due to humidity changes. The bags (or the finish) will slow the rate of change and moderate the peaks if they don't last too long, but if the humidity stays high day after day, it will get through the bag.

 

[dedleytedley]

I had an Aerotech E-30-4 SU motor have a casing failure at ignition. Basically the nozzle with a small section of casing attached blew out the bottom. I noticed the plastic casing was a different appearance from other SU's I've fired. What I'm wondering is if it would be worth the trouble to get a replacement on warranty? Ted