Aerotech E20 not igniting

[TahoeGator]

Hello and Merry Christmas!

I’ve had two Aerotech E20-4W fail to ignite. Each has smoked enough to realize the igniter has fired and the start has failed. In both cases I pulled the motors and deemed them unsafe to retry (soaked in water afterwards). I am using a 12v ignition system. I am pretty sure I pushed the igniter all the way up as far as it would go.

There is the wasted expense of the failed motor, of course, but also the disappointment of not being able to do the launch (Estes Saturn V in this case).

For reference, I swapped to an F44-4W and used the same setup exactly, and the launch went as expected. I’d really like to get my one remaining E20 to work to see the Saturn with a slower burn.

Anything special Aero E20 motors need to ignite?

 

[astronwolf]

Anything special Aero E20 motors need to ignite?

Yes. Another igniter. I would have tried again with another igniter. I use MagnaLites. The E20s can be stubborn, chuffy motors.

 

[tfish]

The E20 motor uses a C-slot for the core. It can be tricky finding the slot and working the igniter all the way to the top of the motor.
https://www.aerotech-rocketry.com/u...a5c-8117-fa20d1f7bc35_e20packageinsertV10.pdf

The F44 uses normal bate(s) grain and the core is centered with the nozzle..which makes it easier to insert the igniter in and get it to the top of the motor.
https://www.aerotech-rocketry.com/u...32aef946_Economax_Instructions_77409-1010.pdf

Tony

 

[John Taylor]

+1 on Magnalite products.
You can put a piece of tape at the proper depth on the igniter to insure it is inserted fully.

 

[DeepOvertone]

I’ve had trouble lighting those as well. A second igniter did the trick. It chuffed a bit and then finally went.

 

[dmgrime]

I've had trouble with almost all of the AT white lightning single use over the years. For C-slot reloads I lightly sand the slot during assembly.

That said, a good hot starter such as wildman little'uns or tiny lighters work magic, and I've also taken to running one of the below up the grain a few times just before launch (prior to inserting the starter). Helps clean off any oxidized propellant ... if I have a misfire I repeat the brush to remove the coating left by the failed ignition.

https://www.harborfreight.com/airbrush-cleaning-brushes-5-pc-68155.html

Best of luck!

 

[neil_w]

Hmm, all my Aerotech E15s have lit right up. Guess I've been lucky so far... (and now I'm probably jinxed).

 

[dpower]

The older white-lightning motors are, the tougher they are to light. With enough persistence (and starters), they'll usually go, unless they're very old and highly oxidized. For stubborn WL motors, copperheads can actually work better, since they burn slower. I keep a few in my range box for such occasions.