Greg,
I’ve had a few of those. One made the ROCKETS Magazine (Volume 10, Issue 1)
LDRS 35 edition. An old-style Estes Monarch (found at Lucerne decades ago) on
an almost-as-old AT D9W-7. It chuffed off the pad on the front row and
proceeded to complete its burn on the ground clutching tightly to the legs of
one of Dierking’s sawhorse pads.
Another old D9 in a Black Brant chased Mike Ostby out of his lawn chair and
imbedded its nose cone tip into the side of one of my plywood rocket boxes
(it’s still there!) prior to ROCstock 41 in June 2015.
Future experimentation with old 24/40 reloads will be on my own or on the away
cells!
Chris
[cid:image003.png@01D3EDDA.30A5C4E0]
From: roc-chat-bounce@xxxxxxxxxxxxx [mailto:roc-chat-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Gregory Lyzenga
Sent: Thursday, May 17, 2018 9:12 AM
To: roc-chat@xxxxxxxxxxxxx
Subject: [roc-chat] Re: Aerotech Motor Hardware
On May 17, 2018, at 9:05 AM, Chris J Kobel
<chris.j.kobel@xxxxxxxx<mailto:chris.j.kobel@xxxxxxxx>> wrote:
Thanks for the offer Mike. I think I’m good in most cases, but I’ve been going
through 24/40 motor sets pretty quickly.
I have (substantial!) motor reloads dating back to 1996 and I consider it a
personal challenge to try to actually use them with positive results instead of
just destroying them. I’ve experimented with igniter design, enhancement, and
grain preparation in order to get them to light. I’ve been able to do this
successfully about 75% of the time, occasionally after multiple attempts with
the same motor. In a few cases, I’ve blown closures and ruined many an Estes
blast deflector plate, not to mention having to rebuild a few rocket. Reusing
a casing after it has spit a closure is a bad idea, ask me how I know….
Chris
As a possibly relevant side note, I tried flying an old 24/40 reload at the
last ROC launch and it didn’t go well. I’m not sure exactly how many years old
it was, but there was quite a bit of white exudate on the surfaces of the
grains. I decided to give it a go anyway… It sat on the pad and chuffed for
several seconds, and then with what little propellant was left, it sort of
grunted off the pad and hit the ground before ejection. Ouch. I decided to
dispose of the other old reloads I have.
- Greg
----------------------------------------------------------
Gregory A. Lyzenga <lyzenga@xxxxxxx<mailto:lyzenga@xxxxxxx>>
Dept. of Physics, Harvey Mudd College (909)
621-8378<tel:%28909%29%20621-8378>
Claremont, CA 91711-5990 mobile (626)
808-5314<tel:%28626%29%20808-5314>