Simple Solid Propellant Question

Simple Solid Propellant Question

Post by David Weinshenke » Fri, 12 Nov 2004 12:52:22



Quote:

> don't make propellants .. besides it's
> tedious and you'll rarely launch anything.

LOL!

Too true!

-dave w

 
 
 

Simple Solid Propellant Question

Post by RowdyYate » Sun, 14 Nov 2004 19:35:47


  It's not possible,

Quote:
> really, to take every precaution, so don't make propellants .. besides
> it's tedious and you'll rarely launch anything.

        I could not disagree more. It's not tedious, it's fun. As for
"taking every precaution", that's not possible in anything. Hell, getting
out of bed is hazardous. Breathing is hazardous. Ever drive or ride in a
car? Talk about dangerous...
        This is similar to the idjits that say you won't save money by
making your own motors. That's hogwash. When was the last time you bought a
K motor for twenty bucks? Or an M for a hundred?
        Takes me an hour and a half to cast three 98mm grains. That's an M
motor. Takes longer to properly prep the rocket.
        Last EX launch, I put up four flights personally, flying J through M
power, and "loaned out" five other motors, ranging from I impulse to a large
L. (No, I didn't sell them. I was offered some cash to offset the cost of
making the propellant, but refused it. I like to showcase my motors. I
received a lot of compliments, and not from only the people flying them...)
        Please don't tell me not to make propellant... If no one ever
experimented with propellant, we would not have a hobby in rocketry...

RY

 
 
 

Simple Solid Propellant Question

Post by Mfreptil » Mon, 15 Nov 2004 02:21:51


Quote:
> Please don't tell me not to make propellant... If no one ever
>experimented with propellant, we would not have a hobby in rocketry...<<

I took it as a standard disclaimer.

Mike Fisher

 
 
 

Simple Solid Propellant Question

Post by Larry Curci » Mon, 15 Nov 2004 08:51:43


The charcoal is doing several things
1) Its reaction temperature is higher, since all of it reacts
     and no water (requiring hear to vaporize and expand it) is released.
     Higher temperature leads to higher burning rate.

2) It is black, and absorbs more energy on the propellant surface
     from the flame than the rest of the stuff does

3) It makes the melted propellant less flowing, and causes more
     voids during casting, making the resultant propellant more
     likely to cause explosions on the launch pad.

The sulfur lowers the ignition temperature of the propellant,
making it a lot more likely that it will ignite in your face. I
appreciate your intention to be safe, but I respectfully suggest
that what you are doing may be more dangerous than you
appreciate.

Not to say that rocket propellants cannot be made safely. It is
hard to learn to make them safely by yourself, though. It is even
harder to do so legally.

Luck and Regards,
-Larry Curcio


Quote:
> Greetings,

> I have a simple propellant question.  I have not seen references to
> this particular mixture, so I'm curious both for the chemistry and
> safety.

> A melted mixture ( kids, don't try this at home !! ) of potassium
> nitrate, sugar, and sulfur - burns reasonably well, but not well
> enough.  Granted there is a difference, in a given reaction, between
> the carbon released from sugar and the carbon available in powdered
> charcoal, I have noticed that the same sugar / KNO3 / sulfer mixture
> burns much faster when modified to include 1% powdered charcoal.

> Is the charcoal acting as a catalyst? - and if so how.

> Could the addition of charcoal lower the effective auto-ignition
> temperature of the mix ?

> Could it be any more dangerous to make ?

> Interesting feedback would be appreciated.

> Cursory cautionary note;  Propellant making is interesting, but cannot
> be done safely without taking every precaution.  It's not possible,
> really, to take every precaution, so don't make propellants .. besides
> it's tedious and you'll rarely launch anything.

 
 
 

Simple Solid Propellant Question

Post by Blahblahblahblahblahbl » Tue, 23 Nov 2004 23:43:42


following up on my own post;

   To the rocket motor maker, of course it's fun (and still tedious at
times)
to make rocket motors, I think that people who post on this topic
ought to be careful with recipies and so forth, as we have a
responsibility to protect children and the not-so-clever from injuring
themselves.  A few words of caution belongs with anything that could
cause harm.

   I would think though, that perhaps Americans should be doubly
advised to not make rockets, as both the culture and election results
clearly show certain hard limits on mental faculties.

   The powdered charcoal appears to be a good means to modulate the
burn rate of sugar fuels, and I will be experimenting with it further
near the 1% level.  I could see from my few tests that charcoal could
turn your core-burning sugar recipe into a mix that burns fast enough
to split the motor casing.  The other danger could be the potential
burn rate of the heated mixture while melting.  I would imagine
scorching hot molten mix would not make a good face mask, especially
if it was burning as well.

-geoffgallo

 
 
 

Simple Solid Propellant Question

Post by Phil Stei » Wed, 24 Nov 2004 00:19:05



Quote:

>   I would think though, that perhaps Americans should be doubly
>advised to not make rockets, as both the culture and election results
>clearly show certain hard limits on mental faculties.

Ok.  So why didn't to specify what country you wanted your answers to
originate from?  Should they come from whatever country you are from?