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E12-0s blow up

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mdrossno1

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Hi;

I was using D11-Ps to launch my Astro Blaster but I can't find them anymore so I bought a pack of E12-0s and epoxied a plug in the end of them and so far two have blown up in the fuselage. Why does this happen? These motors are only a month old and the damage they do is considerable to the fuselage of my A/B. Is there a way to determine if the rest will blow up other than igniting them? Is there a way to store them that I do not know? I keep them in a ziplok bag in a cool, dry location.

Thanks,
MDR
 

crossfire

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E12s have had problems for many years.
 

rms

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Hi;

I was using D11-Ps to launch my Astro Blaster but I can't find them anymore so I bought a pack of E12-0s and epoxied a plug in the end of them and so far two have blown up in the fuselage. Why does this happen? These motors are only a month old and the damage they do is considerable to the fuselage of my A/B. Is there a way to determine if the rest will blow up other than igniting them? Is there a way to store them that I do not know? I keep them in a ziplok bag in a cool, dry location.

Thanks,
MDR
Isn't there an ejection charge in a E12-0, just no delay, they are used for staging. Epoxying the plug in maybe the problem?g
My speculation as I have not flown a E12-0
Greg

Greg
 

Incongruent

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Isn't there an ejection charge in a E12-0, just no delay, they are used for staging. Epoxying the plug in maybe the problem?g
My speculation as I have not flown a E12-0
Greg

Greg
The way staging motors work is by having a solid slug of propellant, the top of which eventually burns through. (The wall of propellant gets thinner as the motor burns, and the middle gets the thinnest and is farthest from the casing walls, so ideally it breaks first.) This sprays forward burning chunks of that BP propellant and hot gas, and hopefully a piece will enter the nozzle of the next motor, still burning, and set it off. The epoxy prevents the top of the propellant slug from burning through by containing the pressure, essentially plugging it.

Depending on who you ask, epoxy plugs may be a violation of the NAR safety code since you're modifying the motor.
 

K'Tesh

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I'm wondering if the OP were to disable the engine retainer, and devise a way for the the motor to eject itself, would that solve the problem of no plugged motors?
 

qquake2k

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Maybe rig up some sort of vent to the outside so you're not kicking empty motor cases out onto the field.
 

bob jablonski

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The last couple years E12 Then E 9 have been having problems. It got to the point I wont sell them
 

Incongruent

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The original question was on storage methods. I believe I instigated the derailing, so sorry about that.

I think the storage method you're using now is good, but what temperature are you launching at?
While you can control how the motors are stored while they're your possession, there's no guarantee that they haven't been heated during transport or while stored at where you got them from. Additionally, it is suspected that (based in data) launching in cold temperatures can crack the grain during the burn because of the greater temperature difference.
 

cavecentral

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Those motors are known to have some failures. I used to epoxy plug Estes motors. Not sure about the if that is a safety code violation for modifying the motor (probably is).

Even D12-3s I scraped off the clay cap and removed the ejection change before plugging them. Of course, that isn't the safest thing to do. I doubt this fits in to the safety code since it is a larger modification to the motor.
 

Incongruent

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Is there a way to determine if the rest will blow up other than igniting them?
Yes. You hit them really hard with a hammer, and if there's a cracking noise or the motor casing deforms, that means it'll probably blow up.
(Don't actually use this method.)

[RETRACTED]
 
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dpower

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What is the date code on your E12-0 motors? The initial batches from 2011 had a high failure rate, but have been quite reliable since then. I would *not* file a MESS report, since the motors were modified.
 

scsager

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Hi;

I was using D11-Ps to launch my Astro Blaster but I can't find them anymore so I bought a pack of E12-0s and epoxied a plug in the end of them and so far two have blown up in the fuselage. Why does this happen? These motors are only a month old and the damage they do is considerable to the fuselage of my A/B. Is there a way to determine if the rest will blow up other than igniting them? Is there a way to store them that I do not know? I keep them in a ziplok bag in a cool, dry location.

Thanks,
MDR
Astro Blaster?!?!

2 CATOS - oh man - please don't use Regular (non-plugged) motors in that classic anymore. If it's still flyable...:facepalm:

Use Google and locate the Aerotech 24mm Reloadable RC motor. Expensive, but a much better alternative.
 

jd2cylman

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Isn't there an ejection charge in a E12-0, just no delay, they are used for staging. Epoxying the plug in maybe the problem?g
My speculation as I have not flown a E12-0
Greg

Greg
There isn't an ejection charge on the -0 motors. His problem was from an actual motor CATO. Putting the epoxy plug wouldn't change anything. There's still a nozzle to let pressure out the proper end. The epoxy plug just keeps burning bits from going forward.
 

Trident

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The hobby shops here do not carry Es due to Hazmat, and I don't want to pay Hazmat charges to mail order them, plus I read these reports often enough to just say "No".

I've just acquired some Estes E/F 29mm BP motors. Makes me wonder if I'll see the same ...
 
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markkoelsch

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I have tried three Estes E motors over the years. Two Cato's. Will not try another. I think of them as rocket disposal charges.
 

chrisudy

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I've flown well over 20 E motors (E12 and E9) without issue...

Chris
 

Charles_McG

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I've flown well over 20 E motors (E12 and E9) without issue...

Chris
Chris, if you still have some inventory of those E9s and E12s, could you please check (and post) the lot numbers? The stock in all the stores around me are lots with reported CATOs. I'm very curious about successful Estes E fliers - are they having good luck with lots others aren't, or are you flying other lot numbers?

Charles
 

burkefj

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Just stick with composite motors, you can use E-11 reloads, or in the RC 24mm casing, E-12's which don't have an ejection charge/delay element.
aerotech also sells single use E-15P 3 packs.

I recommend the aerotech motors only in my rc rocket glider kits(mine are lighter than the astro blaster so I use the E-6 RC motor. I just had a customer fry one of his rc rocket gliders using an E-9.

Frank
 

Zeus-cat

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This is the list of date codes that I have for bad E motors. I have not seen an update in a while.

E9
09-04-12
06-28-11
06-14-01 A
A 01 12 16
A 09 15 14
A 1-12-16

E12
A 08-18-11
A 11 15 11
 

Rex R

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wouldn't a D12-0 have been a better choice?
Rex
 

burkefj

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D's are pretty marginal in the astroblaster at the normal flight weight, 24mm composite E's are much better imho. I only got about 200' in my astroblaster, just time to pitch over and set up for landing.
 

chrisudy

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Finally dug out my motor box. I don't know what date codes I actually flew, but I have odd numbers left on E9-4 with date 10-30-06 and E12-4 of 4-2-12, 6-22-12, and 5-15-12

Chris
 

Charles_McG

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Thanks Chris.

One of the missing pieces in the Estes E CATO saga is -good- flight batch reporting.
 

djs

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One of the missing pieces in the Estes E CATO saga is -good- flight batch reporting.
This- I would like to get more E-9/E-12 motors, but I'm afraid to buy any not knowing what's a "good batch" to get.
 

chrisudy

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I wish I had kept the casings from the good flights...
 

Screaminhelo

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I flew a couple of E's this weekend. Two good flights in my Mega Mosquito. I also have a few casings being used for display and paint wands. I'll try and remember to post the dates when I get home.
 

aerostadt

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I have not changed my bad motor list in awhile, so it is still the same. It does not include any booster motors. The list is as follows:


C11
A 11 08 10
A 06 28 11

E9
09-04-12
06-28-11
06-14-01 A
A 06 28 11 1
A 01 12 16
A 09 15 14
A 1-12-16

E12
A 08-18-11
A 11 15 11
 
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