[sugpro] Re: Hello Sugpro
- From: "Andrej Vrbec" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender "andre09091978@xxxxxxxxx" for DMARC)
- To: "sugpro@xxxxxxxxxxxxx" <sugpro@xxxxxxxxxxxxx>
- Date: Wed, 11 Feb 2015 07:16:39 +0000 (UTC)
I can see that recrystallization might give good results, but when you get to
larger motors requiring 10kg or 20kg of potassium nitrate it seems like a
pretty time consuming, labor intensive and costly procedure. It's probably
cheaper to buy higher quality potassium nitrate in bulk then to make it
yourself from fertilizer grade potassium nitrate. Andrej
From: Ben Brockert <wikkit@xxxxxxxxx>
To: sugpro@xxxxxxxxxxxxx
Sent: Wednesday, February 11, 2015 1:57 AM
Subject: [sugpro] Re: Hello Sugpro
You might be thinking of the quite instructive
http://www.nakka-rocketry.net/knpurify.html
I could see the appeal of using off the shelf stuff, though.
Glad to see sugpro activity.
On Tue, Feb 10, 2015 at 7:49 PM, Michael Monteith
<dmarc-noreply@xxxxxxxxxxxxx> wrote:
> Andrej,
> I thought I had read somewhere that there is a way to separate out
> the anti-caking part. Might of course be in one of my books that's packed
> for the moved and won't be here until like the first week of March. Uggh
> But maybe someone here has surely been through that feat before.
>
> Michael
> --------------------------------------------
> On Tue, 2/10/15, Andrej Vrbec <dmarc-noreply@xxxxxxxxxxxxx> wrote:
>
> Subject: [sugpro] Re: Hello Sugpro
> To: "sugpro@xxxxxxxxxxxxx" <sugpro@xxxxxxxxxxxxx>
> Date: Tuesday, February 10, 2015, 4:30 PM
>
> Ah, OK
> that makes it clearer. I thought that you have a 70cm BRB
> GPS version.No, I
> don't use any clamping. I know that clamping should
> improve density but I haven't yet come to try this. I
> typically get grains to about 97-97,5% of ideal density.
> I did
> quite some experimentation with different grades of
> potassium nitrate. My goal was to develop a mixing and
> casting technique that would allow me to use a fertilizer
> grade potassium nitrate which is very cheap and readily
> available. I've tried many different grades, particle
> sizes, pH values, defoamers, surfactants, vacuum
> degasing, you name it I've done it. In the end I just
> couldn't get the same high density propellant as I get
> when I use a food grade potassium nitrate without anticaking
> agent. I've read that a lot of people use fertilizer
> grade KN with good success but it wasn't working for me.
> Surfactans and defoamers helped to some degree but still
> the density was lower than with a food grade KN. It seems
> that anticaking agents used in this potassium nitrate
> fertilizers have a significant efect on wetting abilities of
> molten dextrose. as they make the KN particle surface more
> hydrofobic. All these problems went away when I switched
> back to a potassium nitrate without anticaking agent, which
> is twice the price of fertilizer grade, but gives very
> good results. So far I
> didn't have any problems with disbonding even in large
> grains. The material I use for the inhibitor is not a
> paper, but a gasket material called Tesnit BA-202, which is
> made of organic fibers and nitrile rubber. I cut the
> material to correct size to fit snugly in the steel tubular
> holder which is then heated in an oven to 150°C as well as
> base and a coring rod. Just before pouring, the mould is
> pulled from the oven and the propellant is cast. Here is the
> link to this material website: http://donit.eu/material/ba-202/ I
> use 0,5mm thickness and the factory that makes it is
> conveniently located just a few kilometers from my home
> :)
> Andrej
>
> From: Richard Nakka
> <richard.rocketry@xxxxxxxxx>
> To:
> sugpro@xxxxxxxxxxxxx
> Sent: Tuesday, February
> 10, 2015 8:55 PM
> Subject: [sugpro] Re:
> Hello Sugpro
>
> Andrej,
> Thanks for the info. I
> actually bought the new BRB900 unit, which
> comes with a simple GPS receiver. Great thing
> about this unit is that
> no amateur radio
> licence is required.
>
> To
> keep this post on-topic, here's a question about your
> propellant
> grains (beauties, by the way). Do
> you cure the KNDX under pressure or
> clamping? To prevent disbonding. I've
> temporarily migrated to KNSB to
> get good
> bonding (I use clamping pressure), but would like to get
> back
> to using KNDX...to hopefully get those
> nice flat thrust curves that
> your motors
> exhibit :-)
>
> Richard
>
>
>
> On Tue, Feb
> 10, 2015 at 1:06 PM, Andrej Vrbec
> <dmarc-noreply@xxxxxxxxxxxxx>
> wrote:
> > Hi Richard
> >
> > It's nice to hear
> from you again. You are right, the propellant is plain
> > KNDX. I've also experimented with
> other sugars (sorbitol, erythritol and
> >
> mannitol) but in the end I decided in favor of dextrose.
> > Bigredbee GPS was a real game changer at
> least for me as I don't have large
> >
> open spaces to fly from. I fly from a small clearing in the
> middle of the
> > dense forest and so far I
> haven't lost a rocket yet. BRB GPS is very easy to
> > set up. First you must download a
> configuration software from BRB website.
> > When you connect the GPS to the computer
> you can make settings like how
> > often do
> you want it to report location and altitude, your call sign,
> output
> > power, etc. On the ground you
> will need some kind of radio setup that can
> > decode incoming APRS data packets sent
> from BRB GPS. There are a lot of
> >
> options but mostly it comes down to how much are you willing
> to spend. Based
> > on my experience I
> would say that the best option for rocket use on the
> > field would be an all-in-one radio such as
> a Kenwood TH-D72 or a Yaesu
> > VX-8GR
> (recently discontinued) or Yaesu FT1DR. These radios are
> pricey but
> > very easy to carry around
> when you are chasing you rocket as you don't have
> > to have several pieces connected with
> cables as would be the case with an
> >
> ordinary radio connected to a TNC (terminal node controler
> such as Byonics
> > TinyTrak4) and a
> separate battery. When the radio receives the data packet
> > from BRB GPS it decodes it and displays a
> current altitude, latitude and
> >
> longitude. When the rocket lands you take the last known
> coordinates and
> > punch them into a
> handheld GPS receiver or if you have one of the above
> > mentioned radios it will display a
> distance and direction to the landing
> >
> site.
> >
> > Andrej
> > ________________________________
> > From: Richard Nakka <richard.rocketry@xxxxxxxxx>
> > To: sugpro@xxxxxxxxxxxxx
> > Sent: Tuesday, February 10, 2015 4:36
> PM
> > Subject: [sugpro] Re: Hello
> Sugpro
> >
> > Amazing
> work, Andrej...! Your rockets are beautifully crafted.
> > Congratulations!
> > I
> particularly like your nice flat thrust curve, that's
> KNDX, right?
> >
> > GPS
> is a clearly a real boon to rocketry recovery, as your
> flights
> > demonstrate. I recently
> purchased a big red bee GPS and look forward
> > to flying it soon....although I must admit
> I haven't quite figured out
> > how to
> use it ...
> >
> >
> Richard
> >
> >
> >
> >
> >
> >
> >
> On Tue, Feb 10, 2015 at 3:16 AM, Andrej Vrbec
> > <dmarc-noreply@xxxxxxxxxxxxx>
> wrote:
> >>
> >>
> Hello guys
> >>
> >>
> I have just recently found out that Sugpro is active again.
> I really
> >> missed
> >> it, as it was always fun to read what
> others are doing with sugar
> >>
> propellants.
> >> Recently I have
> sucessfully flown a sugar rocket to 8km. Here are the
> >> videos
> >> of the
> motor static test and the flight:
> >>
> >> https://www.youtube.com/watch?v=Q2YJtmsqKSU
> >>
> >> https://www.youtube.com/watch?v=z4QmCuDgi_w
> >>
> >> https://www.youtube.com/watch?v=zImHsYWY9-s
> >>
> >> Before that I
> also made a sucessfull flights with a 100mm M motor. You
> can
> >> see the videos here:
> >>
> >> https://www.youtube.com/watch?v=JJlIXvbbtNA
> >>
> >> https://www.youtube.com/watch?v=d_AweYPlwkk
> >>
> >> How many
> subscribers is there currently? I hope that most of the
> folks
> >> from
> >>
> the old Sugpro will join the new list.
> >>
> >> Best
> regards
> >> Andrej Vrbec
> >
> >
> >
>
>
>
>
>
>
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