I've made 3 versions of the motor over the years.
All 4" dia .125 wall 6061
All case bonded
First one was a short proof of concept with 27k ns
Second one was 37k ns
3rd motor was 35kns (extra thick EDPM where the 37k version suffered a
burn through.
All are core burners with double tapered cores.
Dart 1.5" dia
9lbs
6061 AL lower with welded fins
composite upper so that it is radio trans parent for GPS and APRS radio
Booster interstage is milled out of a solid bar of AL with a solid AL tail
cone that mates into it.
G
On Wed, Feb 24, 2016 at 6:31 PM, Clay Reynolds <solarover13@xxxxxxxxxxx>
wrote:
Awesome, I will probably be at BALLS this year and am curious to see how
that works out.
Do you have any details? Size of the motor, dart etc?
What was the case thickness on your carbon cased O motor Richard? Filament
wound tubing I'm assuming?
------------------------------
*From:* arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> on
behalf of Geoff Huber <geoff.huber@xxxxxxxxx>
*Sent:* Wednesday, February 24, 2016 6:51 PM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: TFS Boosted Dart Project
Here is what the second link should have been;
https://goo.gl/photos/NK7CYdEPny6ti8ho9
<https://goo.gl/photos/NK7CYdEPny6ti8ho9>
New photo by Geoffrey Huber <https://goo.gl/photos/NK7CYdEPny6ti8ho9>
goo.gl
On Wed, Feb 24, 2016 at 5:51 PM, Geoff Huber <geoff.huber@xxxxxxxxx>
wrote:
I've been working on a Super Loki clone for years. Made a couple of
attempts already. Here was the last one to fly:
https://goo.gl/photos/ZSFeeKnaCYy5UK4K6
and the flight before that:
https://goo.gl/photos/ZSFeeKnaCYy5UK4K6
They have all been case bonded. One had the interstage fail and the
second suffered a burn through about 4 seconds into flight. Both failed
between m2.5 and m2.7
Unless you are going to have a 2 seconds burn time like the real Loki
darts did. m5 is just not going to happen IMO.
I have this rocket ready to fly again for Balls this year. Will see what
it does. I'd be happy if I hit 100k. I think if all goes well max
velocity will be between m3 and m3.5 at best.
Good luck.
G
On Wed, Feb 24, 2016 at 2:13 PM, <r.hagensick@xxxxxxxxx> wrote:
I have had great luck with double wall carbon fiber using a phenolic
nozzle carrier. My big O motor runs 1200 psi with no issues. I have fired
that twice already. It is single use, but really who is going to reuse a
motor for a project like this.
Richard Hagensick
----- Original Message -----
From: William Claybaugh <wclaybaugh2@xxxxxxxxx>
To: arocket@xxxxxxxxxxxxx
Sent: Wed, 24 Feb 2016 16:58:41 -0500 (EST)
Subject: [AR] Re: TFS Boosted Dart Project
Clay:
You should spend some time reading up on the RRS dart project; that is
the quick way to answer this and many future questions.
The booster fins were black anodized aluminum, 1" thick and bolted from
inside the motor.
At the scale you are working I'd bet a fair amount that a titanium case
at 0.050" (or less) will prove higher performing; aluminum is not the
optimal metal for motor cases.
Bill
On Wednesday, February 24, 2016, Clay Reynolds <solarover13@xxxxxxxxxxx>
wrote:
Thanks for the info! What were the fins on the booster?
My booster is a 37.5kn motor with a .065" walled aluminum case. Roughly
75% that of the super loki. Even with that thin of a case I have a yield
strength of 1,350psi. I'm running a max Pc of 650psi. The super loki hit
velocities around M5. As of right
now my dart is a couple pounds lighter and my case is just 6.77lbs.
I'll be hitting M6 around 10-15k.
On Feb 24, 2016, at 5:31 AM, "William Claybaugh" <wclaybaugh2@xxxxxxxxx>
wrote:
The RRS Dart used double wedge fins in stainless steel that were welded
to the stainless dart body.
Burnout was at about Mach 4.2 at 12,000 feet. The recovered dart
showed no fin damage.
How you going to get to Mach 6? At what altitude?
Bill
On Tue, Feb 23, 2016 at 9:24 PM, Clay Reynolds
<solarover13@xxxxxxxxxxx> wrote:
Hello all,
I am new to this list, and was referred to this group by a friend.
I am currently working on a 4" boosted dart project. Very similar in
size and scale to the Super Loki Dart. (which some of you may be familiar
with)
Preliminary numbers have my rocket between mach 5.8-6.3 and 450K. Any
of you have experience with hypersonic flight? More specifically in fin
design? At these speeds I'm not only worried about flutter, but heating.
I can add more information if you're interested, just wanted to see if
any of you have experience with these extremes.
Thanks!
-Clay
