Home made AP propellant/Simplest solid rocket propellant?

Home made AP propellant/Simplest solid rocket propellant?

Post by Mauritz Geyse » Tue, 29 Feb 2000 04:00:00



Hi to you  all.

Some years ago I try my hand at building and launching my own rocket using
propellant I made myself. Unfortunately the rocket exploded on the launch
pad.

As far as I can remember I used Ammonium perchlorate  (that I had to make in
a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
for me to say that the reason way my rocket exploded like a huge firecracker
could have been due to the Iron oxide? If I only want to use polyester and
ammonium perchlorate, what mixture ratio should I use?

That is the simplest solid rocket propellant that I can make using chemicals
that a readily available?

Mauritz

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Dan G » Tue, 29 Feb 2000 04:00:00


First, I hope you didn't put that motor in the rocket before even 1 static
test...

Anyways... Firefox has a book dedicated to AP composite propellants.
www.firefox-fx.com
I want to get it soon, myself. Check it out.


Quote:
> Hi to you  all.

> Some years ago I try my hand at building and launching my own rocket using
> propellant I made myself. Unfortunately the rocket exploded on the launch
> pad.

> As far as I can remember I used Ammonium perchlorate  (that I had to make
in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge
firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

> That is the simplest solid rocket propellant that I can make using
chemicals
> that a readily available?

> Mauritz



 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Group 74 » Tue, 29 Feb 2000 04:00:00


Quote:

> Hi to you  all.

> Some years ago I try my hand at building and launching my own rocket using
> propellant I made myself. Unfortunately the rocket exploded on the launch
> pad.

> As far as I can remember I used Ammonium perchlorate  (that I had to make in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

> That is the simplest solid rocket propellant that I can make using chemicals
> that a readily available?

> Mauritz


Hello Mauritz,  While most of us here on the model rockets mewsgroup
prefer to buy commercially made rocket motors, there are groups of
people who can give you quailified answers to the above question and the
others you have that are sure to follow.  Check out this web page I've
made especially for guys like you:

http://www.everett.net/users/bloomer/propelant.html

Enjoy!

Steve Bloom
Seattle Area Rocket Guy

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Ron McClell » Tue, 29 Feb 2000 04:00:00


Hey Mauritz,

I'm not gonna be of any help with your posted problem, but I will say this: if
you're gonna experiment with your own formulations, you should test extensively
before you stuff it in a rocket and attempt a launch.

The simple fact you put it in a rocket in the first place and are asking
questions about formulations without giving the specific information as to
ratios of the materials used tends to indicate you are in WAY over your head.

If your rocket had developed just enough thrust to get into unstable flight
before exploding, you would have essentially had an IYBM (InterYard Ballistic
Missile)
If you got hurt doing that, it would blemish the entire hobby. The media
wouldn't say  "Some guy blew himself up with a homemade explosive concoction",
they'd say " A model rocket killed a guy today".

If you must build your own, (and that is a VERY bad idea) you need to study up
on the science of propellent fuels in general. You simply don't know enough
about it yet.

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Curtis Schol » Tue, 29 Feb 2000 04:00:00


Mauritz:

   I think you would be better served by getting subscribed to the
Arocket mail list. I would do this before you get flamed here.

Curtis Scholl

Quote:

> Hi to you  all.

> Some years ago I try my hand at building and launching my own rocket using
> propellant I made myself. Unfortunately the rocket exploded on the launch
> pad.

> As far as I can remember I used Ammonium perchlorate  (that I had to make in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

> That is the simplest solid rocket propellant that I can make using chemicals
> that a readily available?

> Mauritz


 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Tai F » Tue, 29 Feb 2000 04:00:00


Quote:

> As far as I can remember I used Ammonium perchlorate  (that I had to make in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

It could be air pockets inside the propellant grain. I think I heard a
story about some guy built a rocket with homemade APCP, and while he was
hooking up someone pressed the buttom, and it seem the propellant foamed
or something, and blew up right next to the guy..... yes he lived to
tell the story but its not a pretty picture... If you want to make
motors go join some motormaking club and read alot because those
propellant are real sensitive to air pockets and if the burn hit one the
rocket blows up. If you make propellants because you want it cheap then
buy one because you need alot of equipment to make APCP safely.
--
Tai Fu
NAR# 76089
Website: http://web.wt.net/~taifu
 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Mordecai Schmeeglefar » Tue, 29 Feb 2000 04:00:00


Quote:

> Hi to you  all.

> Some years ago I try my hand at building and launching my own rocket using
> propellant I made myself. Unfortunately the rocket exploded on the launch
> pad.

> As far as I can remember I used Ammonium perchlorate  (that I had to make in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

> That is the simplest solid rocket propellant that I can make using chemicals
> that a readily available?

-----
Sounds like you didn't test your engine on the ground first.  I imagine
you didn't do a few other things any prudent amatuer rocketeer would do
as well. You're lucky that engine blew up on the pad and not in your
face.

There is a sliding scale:
1] Safely and reliably flying rockets with pre-assembled engines (estes,
quest, aerotech single use).
2] Safely and reliably flying rockets with engines you assemble from a
kit (aerotech rms).
3] Safely and reliably flying rockets with engines you make to a
pre-established tested design (thunderflame).
4] Safely and reliably flying rockets with engines you make and design
and test yourself.

If you haven't mastered 1-3, you have no business doing 4.  If you've
mastered 1-3, you wouldn't be posting the question.

The chemistry part is simple, almost trivial. You can add any one of a
dozen oxidizers to one of a million fuel bases, with your choice of
accelerants, suppressants, binders and stabilizers.  They all work if
you know what you're doing, all of them will get you killed if you
don't. Again, if you have to ask, you shouldn't be doing it.

The techniques and procedures required to safely and reliably
manufacture rocket engines are not simple.  You will not be able to
safely and reliably manufacture a rocket engine by downloading a
"recipe" off the internet.  Any such "recipe" you can find is a recipe
for disaster.

Your rocket did not cato because the engine had iron oxide in it.  It
failed because You didn't know the required techniques and procedures to
make a reliable and safe rocket engine.  You ask a trivial chemistry
queation, when there are many non-trivial engineering questions you
didn't ask.  

I'm not telling you this to rain on your parade or be a joykill.  I'm
interested in rocket engine design and manufacture myself, but I haven't
mastered 2] yet, so I'll focus on it .  When I've certified level 3 on
RMS and mastered hybrids, I'll move on to 3] Thunderflame!.  But that'll
take a while, and I'll need to get some acreage and some insurance, and
some liscencing to do it.  You _did_ get insurance before you tried to
launch your homemade rocket, right?

mordecai

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Dave/Kristin Ha » Wed, 01 Mar 2000 04:00:00


: As far as I can remember I used Ammonium perchlorate  (that I had to make in
: a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
: for me to say that the reason way my rocket exploded like a huge firecracker
: could have been due to the Iron oxide? If I only want to use polyester and

No, it is not right for you to say that the explosion was due to the use of
iron oxide.  Or at least, it may not be right.  Iron oxide is a perfectly
adequate burn rate catalyst for AP based motors (in fact, it's the industry
standard).  But I suspect you know that or you wouldn't have used it.  There
are *LOTS* of reasons why that motor may have gone kablooee.  Among them...

Insulater/propellant interface debond.
Too small a core resulting in an unplanned erosive burn.
Air pockets in the propellant grain.
Too small a nozzle throat.
Defective motor case.
Non-homogeneous propellant (read: not well mixed).
Igniter debris clogging nozzle.
*** combustion instability.
Standing waveforms within the motor.

...and that's just off the top of my head.

--
David Hall
Propulsion Geek At Large

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Abdul M. Ismai » Wed, 01 Mar 2000 04:00:00


Mauritz,

Try accessing http://www.space-rockets.com

The book, video and Windows based software uses AN as an example but leaves
the user to use whichever chemical combination you wish. It's written by a
professional aerospace engineer and it a real gem of a book for any serious
enthusiast.

Abdul

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Bruce Kirchn » Wed, 01 Mar 2000 04:00:00


Quote:

>It could be air pockets inside the propellant grain. I think I heard a story

about some guy built a rocket with homemade APCP, and while he was hooking up
someone pressed the buttom, and it seem the propellant foamed or something, and
blew up<

Destined to become a classic Tai Fu post! Attaboy Tai!

:-)

--

Bruce Kirchner
TRA L2 #5888       NAR #69850
Michigan Team 1   HUVARS
Visit My Rocketry Home Page - http://members.aol.com/balthezar/index.html
Proud Gun Owner!

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Dan G » Wed, 01 Mar 2000 04:00:00


Whoah! There is one? How do I subscribe?


Quote:
> Mauritz:

>    I think you would be better served by getting subscribed to the
> Arocket mail list. I would do this before you get flamed here.

> Curtis Scholl


> > Hi to you  all.

> > Some years ago I try my hand at building and launching my own rocket
using
> > propellant I made myself. Unfortunately the rocket exploded on the
launch
> > pad.

> > As far as I can remember I used Ammonium perchlorate  (that I had to
make in
> > a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it
right
> > for me to say that the reason way my rocket exploded like a huge
firecracker
> > could have been due to the Iron oxide? If I only want to use polyester
and
> > ammonium perchlorate, what mixture ratio should I use?

> > That is the simplest solid rocket propellant that I can make using
chemicals
> > that a readily available?

> > Mauritz


 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by bob fortun » Wed, 01 Mar 2000 04:00:00


Quote:

> Whoah! There is one? How do I subscribe?

Hey Dan, It's easy.  In the subject line of your next post to RMR put
"Attention aRocket"
and then in the body of the message put "subscribe"  leaving out the
quotation marks of course.  It's a piece of cake.

Someone will sign you right up.

Bob

 
 
 

Home made AP propellant/Simplest solid rocket propellant?

Post by Dusti » Thu, 02 Mar 2000 04:00:00


The people at:
http://www.sonic.net/~brucel/explosivegraphics.html
can share some of their experiences with you.
Quote:

> Hi to you  all.

> Some years ago I try my hand at building and launching my own rocket using
> propellant I made myself. Unfortunately the rocket exploded on the launch
> pad.

> As far as I can remember I used Ammonium perchlorate  (that I had to make in
> a lab), Aluminum powder, Iron oxide and polyester as a binder. Is it right
> for me to say that the reason way my rocket exploded like a huge firecracker
> could have been due to the Iron oxide? If I only want to use polyester and
> ammonium perchlorate, what mixture ratio should I use?

> That is the simplest solid rocket propellant that I can make using chemicals
> that a readily available?

> Mauritz