Question on plugged motors

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Since the Estes D11-P and E9-P motors are no longer widely available, I was wondering if one could convert a D12-0 or E12-0 booster motor by pouring epoxy into the top and plugging it? I know AT makes a composite RMS plugged casing for BGs but I was looking for an economical alternative. Any concerns or safety issues?
 
Sure you can, however it invalidates the certification making the motor EX. You can fly the motor only at TRA research events or at your personal flight location and risk. Plugging a motor is modifying hence the EX designation, and its a violation of the Model Rocket Safety Code about modifying motors.
 
What is this for, rocket glider or rocket?

I too do this often. For me, it is mostly things like saucers and monicopters. On a few of by bigger clusters, most of the mounts are plugged and this helps keep the motors from ejecting or charring the inside.

But, Rich is right on all counts. MDRA allows this.
 
What I was getting at, if for RC rg, don't use those at an ama field, as they require following nar rules, but private fields are fine.
 
What I was getting at, if for RC rg, don't use those at an ama field, as they require following nar rules, but private fields are fine.

Yeah, this will be for r/c gliders. The AT casing and reloads are hard to find, and expensive. But no sanctioned events here, all casual flying at approved public parks (Hawaii). Don't see how AT can charge $90 for a 24 /20-40 case while their 24/40 case sells for half that. I know it's a niche market but give us a break, sheesh. Anyway, thanks guys, and Happy New Year!
 
The Aerotech rc casing is machined from solid bar stock, not tubing since it has a solid end, so is more time and expense to make, I normally sell the casings at around $60 when I can get them, I personally would never risk an Estes 24mm E bp motor in any of my RC rcrgs that have $150-$200 invested since I've seen too many personally fail in a way that destroys models, I've had 0 failures in over 1000 e6 flights in 3 casings just in the last 3 years, to me it's foolish economy, but to each his/her own.

It's too bad that being in Hawaii you can't have the reloads shipped USPS ground which makes the reloads not much more than Estes motors.
 
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The Aerotech rc casing is machined from solid bar stock, not tubing since it has a solid end, so is more time and expense to make, I normally sell the casings at around $60 when I can get them, I personally would never risk an Estes 24mm E bp motor in any of my RC rcrgs that have $150-$200 invested since I've seen too many personally fail in a way that destroys models, I've had 0 failures in over 1000 e6 flights in 3 casings just in the last 3 years, to me it's foolish economy, but to each his/her own.

It's too bad that being in Hawaii you can't have the reloads shipped USPS ground which makes the reloads not much more than Estes motors.

Yes, look at page 3 of my Dynasoar Pegasus rocket glider thread for an example of what can go wrong with an E motor.... (old E9-P that lost exhaust plug).

https://www.rocketryforum.com/showthread.php?138183-Dynasoar-Pegasus-RC-B-G-from-Arkansas/page3


 
I am just not a fan of plugging motors.

Another possible solution is an exhaust outlet? I have an R&R Rocketry Delta RC rocket glider kit (on my To Do list for 2018) that shows a design for an L-shaped tube attached to the engine holder to deflect the ejection charge.
 
There was once was a man named Plato
Who opted against a JATO.
So he went out to Estes
Because they're the bestest
And suffered an E9 CATO!
 
Yes, porting can be done to avoid plugging, however you still are flying a BP 24mm E motor...The plugging of the motors is not the problem, the problem is that the estes E motors have a non zero failure rate and the failure is typically catastrophic. I'd fly them in rockets that are Estes since Estes will replace motor and kit, but not in something that I had a lot of $$ invested in. I mean at every launch I attended, 6-7 last year, out of the 10-20 estes BP 24mm E-9 and E-12 motors I saw flown, I personally witnessed 1-2 failures at each launch. I don't know how they were treated or handled or any date codes. I have not seen this with the D motors. I'm sure a lot of people fly these motors and have no problems, all I can say is I have not personally witnessed a 100% success rate with them, but I have in the 24mm E-6 glider motors in over 1000 flights in the last three years. The only issue I've ever seen in the 24mm glider motors was 5 years ago, there was a batch that was made with blackjack propellent instead of blue thunder, they just sat on the pad and burned for 20 seconds with no thrust.

Frank


I am just not a fan of plugging motors.

Another possible solution is an exhaust outlet? I have an R&R Rocketry Delta RC rocket glider kit (on my To Do list for 2018) that shows a design for an L-shaped tube attached to the engine holder to deflect the ejection charge.
 
Sure you can, however it invalidates the certification making the motor EX. You can fly the motor only at TRA research events or at your personal flight location and risk. Plugging a motor is modifying hence the EX designation, and its a violation of the Model Rocket Safety Code about modifying motors.

Yes, the epoxy plug would make it a non certified motor.
Tripoli Research rules do not allow black powder motors.

M
 
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