Thank you for the kind words, Richard. None of this would be possible
without the groundwork you and others laid.
I've been using KNDX. I see EX as a way for me to gain hands-on experience
and it drives me to learn and expand my knowledge further. For example,
since I begun my project, I've learnt part design in CAD and I've had my
parts machined or printed and my knowledge in electronics has improved
tenfold. I wish to associate my future with the aerospace field and I'm
planning on getting a BA in Mechanical Engineering after I finish
high-school. Experience like this sure should look good on my resume later
on :)
When it comes to specific targets with this campaign, I plan to attain
greater thrust & greater pressures. Once I have enough trust in the motor,
I'd love to do chamber pressure measurements. I have bought a pressure
transducer, but I must say it is a bit dubious. I also have bought a proper
hydraulic line for the pressure transfer and the connections for it, all it
needs is a thread in the bulkhead.
On Wed, Oct 23, 2019 at 11:38 PM Richard Nakka <richard.rocketry@xxxxxxxxx>
wrote:
Congratulations, Arvids, that was a nice test firing. Your test apparatus
has the appearance of good design and workmanship. What kind of propellant
were you using? Do you have any particular goals in mind for your rocketry
testing?
Richard
On Wed, Oct 23, 2019 at 3:05 AM Arvīds Bāliņš <arvidsbalins@xxxxxxxxx>
wrote:
Good day!
I’ve been told about this list by Rick M. I’d like to introduce myself.
My name is Arvids, I’m from Latvia and I’m currently in the final year of
highschool. My first run-in with sugar engines was around 2 and a half
years ago, when I was making these terribly dangerous engines all thanks to
the infamous KOTR video on YouTube. I was lucky enough to have someone
explain me the dangers of what I was doing back then and after that, I set
myself on the right path - started reading RPE & Nakka, doing simulations,
working on electrical ignition and on a “test pad computer”.
I had my first proper engine test around a month ago. The engine was a
test article, meant to test out whether the engine performs as planned and
doesn’t CATO. This was also my first time going to the private test site, I
could test out my set-up procedures and see how long it takes.
The engine contains 2 grains (29mm wide, 10mm core diameter and a length
of 53mm). Casing is made out of 40x2.5mm 6061-T6 Aluminium tube and the
bulkhead and nozzle is made of C45 steel. In the video, you will notice
that the nozzle has no divergent section. I made the decision to make it
only convergent to save time and money on machining, as it would not affect
the accomplishing of the goals I set out for this test.
Here’s the video:
https://www.youtube.com/watch?v=l9yxWlVNi6Y
The test was a partial success. The motor performed as expected and did
not CATO(hooray, but obviously expected as the safety factor was huge). The
failure is on the electronics side - although the countdown proceeded
nominally and ignition was successful, there must have been an issue with
writing the recorded data to the SD card, as the readings from this firings
could not be found on it after the test. Currently, I’m in the middle of
investigating the causes for it. I was very interested in seeing the data
from the thermistor, as it would let me know how effective the liner was
and let me update the safety factor calculations.
If anyone has any further questions about the hardware or the
electronics, I’d love to talk about it further. I have pictures of the
parts post firing.
My email is arvidsbalins@xxxxxxxxx
Have a nice day!
