Rick,
Completely agree, distance is non optional no matter what the material,
something to hide behind does not hurt either. "And remember this, there is
no more important safety rule than to wear these: safety glasses!" Those
sharp bits could put your eye out even if they have slowed down
considerably.
-Bill
On Mon, Mar 4, 2019 at 1:00 PM Rick Maschek <dmarc-noreply@xxxxxxxxxxxxx>
wrote:
Bill,
" *I also had my first PVC motor CATO experience. It does shatter into
small pieces, but they do not travel far at all because of their high drag
to weight ratio*."
Yes, all my experience with pvc motor cases is that they shatter into
small pieces, sometimes hundreds depending on the motor size. I call them
'shotgun CATOs'. Lots of fragments that usually don't travel far. A keyword
is '*usually*'. I have found pvc bulkheads and nozzle assemblies with
sharp jagged edged points from the glued in ends broken away over 100' away.
I'm just mentioning this so people don't get the idea they are safe to be
near when igniting as I've seen the use of 25' long Estes controllers used
to fire sugar EX pvc motors, something that IS NOT SAFE to do. Not what was
done in this photo but I hope you get the idea. I personally NEVER fire any
sugar motor closer than 100' (100' ignition extension cord(s) to the
battery are your friend) and that is usually when standing behind something
I can duck.
Rick
On Monday, March 4, 2019 8:53 AM, Nikolai Nielsen <
nielsen.nikolai86@xxxxxxxxx> wrote:
Well all the motors were made exactly the same. Two had RIO and katoed,
two were plain KNSU and didn't kato. The design works fine with and without
RIO when new.
On Mon, 04 Mar 2019, 5:28 PM Bill Kuker, <bkuker@xxxxxxxxxxxxx> wrote:
Huh, just a couple weeks ago I went 3 CATOs for 4 motors on a design that
had a perfect 14/14 success rate previously. KNDX grains were stored in
fridge with desiccant for 2+ years. I always use a KNSU header grain with
KNDX for fast ignition, those grains were fresh.
I also had my first PVC motor CATO experience. It does shatter into small
pieces, but they do not travel far at all because of their high drag to
weight ratio. I already knew this from... extensive non-rocket pvc
exploding shenanigans... but confirmed it for real. Be safe though, my
anecdote does not by itself constitute a final conclusion on the matter.
On Mon, Mar 4, 2019 at 10:05 AM Richard Nakka <richard.rocketry@xxxxxxxxx>
wrote:
But did these motors have the same safety margin? Perhaps these motors
that did not CATO were more tolerant to higher pressure.
Richard
On Mon, Mar 4, 2019 at 8:36 AM Nikolai Nielsen <
nielsen.nikolai86@xxxxxxxxx> wrote:
i had some motors of the same size and age that didnt have RIO and they
didnt kato. the RIO is doing something
Nikolai Nielsen
On Mon, 4 Mar 2019 at 16:29, Richard Nakka <richard.rocketry@xxxxxxxxx>
wrote:
My experience regarding long term storage is with KNSU, KNSB and KNDX.
I've used both KNSB and KNDX after being stored for about a year with no
noticeable change in performance. Storage was in redundant zip-lock bags at
room temperature in a relatively low humidity environment (approx. 60% +'/-
10%). I've stored KNSU for long durations in a zip-lock bag in a freezer
with similar results (this is probably your best bet for storage). As noted
by others, *never *store your grains with desiccant for more than a week
or so. The residual moisture is sucked out and the burn rate increases
enough such that a CATO could result when fired (depending on your safety
margin). Moisture is a burn rate inhibitor. I'm guessing but the effect
could be exacerbated by RIO.
On Sat, Mar 2, 2019 at 5:24 PM Nikolai Nielsen <
nielsen.nikolai86@xxxxxxxxx> wrote:
6 months to a year and KNSU
On Sun, 03 Mar 2019, 1:09 AM Ben Brockert, <wikkit@xxxxxxxxx> wrote:
What is "old" in this context? And is this KNSB or plain sugar or
sugar/corn syrup or what?
On Fri, Mar 1, 2019 at 8:33 AM Nikolai Nielsen
<nielsen.nikolai86@xxxxxxxxx> wrote:
limited life span in terms if usability. I tested some old motors that had
I've recently observed that old fuel (atlest fuel with RIO in it) has a
RIO in it and they all katoed. I also has some old powdered fuel used for
making hand rammed motors and the the motors that I make now with it all
Kato. I made new fuel and it worked fine. I suspect that maybe the RIO
catalises some side reactions that makes the fuel become unstable? Anyone
able to shed some light on what's going on here?
