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Hennig Brand
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Wikipedia has a good page on solid fuel rockets. There can be errors in Wikipedia pages, but they are normally mostly correct. If you require a more
trusted reference, look further.
http://en.wikipedia.org/wiki/Solid-fuel_rocket#Zinc.E2.80.93...
"
Zinc–sulfur (ZS) propellants
Composed of powdered zinc metal and powdered sulfur (oxidizer), ZS or "micrograin" is another pressed propellant that does not find any practical
application outside specialized amateur rocketry circles due to its poor performance (as most ZS burns outside the combustion chamber) and incredibly
fast linear burn rates on the order of 2 m/s. ZS is most often employed as a novelty propellant as the rocket accelerates extremely quickly leaving a
spectacular large orange fireball behind it."
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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ecos
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Quote: Originally posted by Hennig Brand ![](images/xpblue/lastpost.gif) | Wikipedia has a good page on solid fuel rockets. There can be errors in Wikipedia pages, but they are normally mostly correct. If you require a more
trusted reference, look further.
http://en.wikipedia.org/wiki/Solid-fuel_rocket#Zinc.E2.80.93...
"
Zinc–sulfur (ZS) propellants
Composed of powdered zinc metal and powdered sulfur (oxidizer), ZS or "micrograin" is another pressed propellant that does not find any practical
application outside specialized amateur rocketry circles due to its poor performance (as most ZS burns outside the combustion chamber) and incredibly
fast linear burn rates on the order of 2 m/s. ZS is most often employed as a novelty propellant as the rocket accelerates extremely quickly leaving a
spectacular large orange fireball behind it."
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thx Hennig, I already aware about that but I dont intend to use it as propellant but as igniter
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Hennig Brand
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Apologies, I wasn't following the thread closely enough. How about thermalite fuse/igniter cord? It is very hard to obtain at this point from what I
have heard, but it can be improvised. It is apparently very good for difficult to ignite rocket engines among other things.
http://www.brianredmond.net/dwilliams/thermalite/thermalite....
I have made something similar several times, just from what I had lying around. The copper wire core was obtained by stripping the insulation off of
old telephone wire. I have made some with potassium perchlorate and chlorate and some with just chlorate. Some was made with magnesium powder and some
with just fine flake aluminum. The binder I used was NC, because I haven't obtained other binders yet. It all worked well; some was hotter burning
than others depending on the composition. Short pieces of this apparently work very well as rocket igniters.
[Edited on 5-3-2015 by Hennig Brand]
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Bert
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Quote: |
but whats wrong with Zn+S ?
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I have never used it for igniting hard to light rocket fuels- After reading of some accidents to people handling "micrograin" fuel, I never made any
more of it, there are higher performance fuels with better safety. Never made any rockets larger than 1/4" bore with this, and even that was 40 years
ago.
Zn + S fuel is more like a slow flash powder than a rocket fuel, from my very limited experience. It MIGHT work as an igniter, but I know from
personal experience that the Copper or Manganese oxide + Al thermites have worked well as igniters, and that these can be regulated somewhat in burn
speed & ignition sensitivity by changing the Al powder particle size & shape.
If you experiment, let us know how it does.
(Edit)
I have just found some very fine Zn powder in my chemical storage, of a type used in anti corrosion paints. Some years back, a professional painter
had 50 lb. buckets of this that were punctured by a fork lift, he gave me the remaining material rather than try to salvage it and use it on a
government bridge painting project- It appears to be just fine, not oxidized or contaminated. I will try to make time for a small experiment-
[Edited on 5-3-2015 by Bert]
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ecos
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great, I will provide results of my experiments soon , maximum after 2 days.
I forgot that I have sulfur and Al.
Quote: |
Aluminium sulfide is readily prepared by ignition of the elements[6]
2 Al + 3 S → Al2S3
This reaction is extremely exothermic and it is not necessary or desirable to heat the whole mass of the sulfur-aluminium mixture; (except possibly
for very small amounts of reactants). The product will be created in a fused form; it reaches a temperature greater than 1100 °C and may melt its way
through steel. The cooled product is very hard.
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I received my shipment now and it contains (Mg ribbon , activated charcoal , Fe2O3)
Since I have Mg ribbon , I can prepare Fe2O3/Al and this is good news.
regarding MnO2/Al , I found it on : http://www.nakka-rocketry.net/thermites.html#TH5
the most interesting that it can be ignited with a Mini bulb igniter. I will give it a try but I need to find a better source than carbon batteries
.
I am very interested to try ammonpulver. charcoal that I received needs to be fine powder. I will use my coffee grinder for this purpose.
I went through the book you provided.
Quote: |
Ammonpulver which contains no potassium nitrate—in a typical example ammonium nitrate 85 per cent and charcoal 15 per cent, or a similar mixture
containing in addition a small amount of aromatic nitro compound is flashless and gives at most only a thin bluish-gray smoke which disappears
rapidly. Rusch has published data which show that the temperature of the gases from the burning of ammonpulver (ammonium nitrate 80 to 90 per cent,
charcoal 20 to 10 per cent) is below 900°, and that the ballistic effect is approximately equal to that of ballistite containing one-third of its
weight of nitroglyccrin.
Ammonpulver has the advantages of being cheap, powerful,flashless, and smokeless. It is insensitive to shock and to friction, and is more difficult to
ignite than black powder. In use it requires a strong igniter charge. It burns rapidly, and in gunnery is used in the form of single-perforated
cylindrical grains usually of a diameter nearly equal to that of the space within the cartridge. It has the disadvantages that it is extremely
hygroscopic and that it will not tolerate wide changes of temperature without injury.
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I tried to search about the Isp for Ammonpulver but couldn't find anything useful on internet. I also couldn't find much info about its power or
different compositions with metal or sulfur.
any idea of different compositions ?
[Edited on 5-3-2015 by ecos]
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ecos
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the Mg ribbon is driving me crazy , when it touch anything while burning it stop!
the ribbon is made since 2009 , would that be a problem ?
I prepared a sample of ammonpulver (85% AN and 15% charcoal). I used Mg strip to ignite it.
the result is failure . here is a video : https://www.youtube.com/watch?v=4G5C28O2JQA
I had the similar behavior while trying to ignite S/Al !
any suggestions ?
[Edited on 6-3-2015 by ecos]
[Edited on 6-3-2015 by ecos]
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Bert
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That's pretty normal behavior for Mg ribbon- It loses heat to contact with solids or liquids, needs air to burn, won't behave like a fuse that has an
oxidizer and easily goes out, very annoying!
Lots of lab manuals recomend igniting things with Mg ribbon. Very few experienced pyrotechnists have much use for it.
Please describe mixture ratios by weight and particle size for all reactants of your various mixtures that won't ignite...
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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ecos
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The charcoal/sulfur/Fe2O3) are almost dust but Al is homemade using my coffee grinder (I cut the Aluminum foil into small parts and added some water
then used my grinder to make it powder, after that i dried it)
the ratio was 85% AN and 15% charcoal
regarding my S/Al thermite , the ratio was 2:1
I used the grinder for AN and it is almost powder !
[Edited on 6-3-2015 by ecos]
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Dornier 335A
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My experience with ammonpulver is that it burns cleanly and with high gas output, but only if continuous heat is applied. This was for tests in the
single-gram scale though, so a large, compressed fuel grain will of course work better. A little pressure won't hurt either.
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ecos
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how did you mix the An/C ? I use a tablespoon since i was afraid to use my coffee grinder .
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I carefully milled them together between two steel plates. It might be relevant that I used high quality willow charcoal, the same as I use for black
powder.
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ecos
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Ok , I took the risk and used coffee grinder to mix AN/C.
I made 10 trials to test AN/C using Mg ribbon , all the trial the ribbon didn't ignite the mixture, finally it gave smoke and thats it .
video : https://www.youtube.com/watch?v=YCmqHLsLjR8
whats wrong ?
[Edited on 7-3-2015 by ecos]
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PHILOU Zrealone
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Stop with Mg ribbon!
Use christmass sparklers ![:D](./images/smilies/biggrin.gif)
For me it works quite good to ignite thermite or other hard to ignite powders!
Beware that a single spark may set your powder pile in fire...so usually it is a good idea not to put the sparkler at the vertical on top of the
powder...
--> Stick it at 30° from horizontal!
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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ecos
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yes, I wish I can make sparklers, making KNO3 is very annoying using AN since ammonia gas kills me.
I am thinking about electronic igniter like this :
![](http://www.thefintels.com/aer/noi8.jpg)
would this work with thermite? I can use copper wire instead of steel wool.
[Edited on 7-3-2015 by ecos]
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Hennig Brand
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I have used single strands of fine steel wool as bridge wires before I obtained a roll of fine nichrome. It does work quite well, I even did some rock
blasting using igniters made with steel wool and never had a failure. Steel wool is often not very uniform; some strands can be weak in one of more
places and break easily. A simple test is to select a strand and then put it under a bit of tension (pull on it), if it is too thin at any point along
its length it will break. Once a strong, fairly regular, strand is selected it can be soldered to a pair of lead wires. A common fuse head composition
is black powder with nitrocellulose lacquer binder, but it sounds like you need something hotter. You could do the first layer in black power and NC
and then an outer layer of a hotter burning composition.
You could make electrical igniters with "Thermalite" composition type match heads. A friend of mine still has a couple of rolls of commercial
Thermalite fuse and it really is wonderful stuff, very hot burning. It is not a core burning fuse, but it will still continue burning even if
submerged in water from what I have heard. You would think I have stock in this company the way I am pushing this stuff. ![:D](./images/smilies/biggrin.gif)
Sparklers really do burn hot. I wonder how easy it would be to use a bit of sparkler as a component of an electric match head?
[Edited on 7-3-2015 by Hennig Brand]
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ecos
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black powder and NC ? Wow , it is more easier to make a bomb than making a
rocket !
I think I can add Al powder to the steel wool , it would increase its efficiency for sure.
![](http://www.thefintels.com/aer/noi9.jpg)
reference of the idea : http://www.thefintels.com/aer/noi.htm
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I made my first test using wool and Al powder : https://www.youtube.com/watch?v=WcQg5cAVFVY
I think it is promising , what do u think ?
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Hennig Brand
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The electric match heads made of black powder bound in NC behave differently when lit than loose black powder or fibrous NC, they burn with a quick
flash that isn't too violent. What you have done may work, but it is very crude. A more consistent and focused heat/energy source would be more
desirable, such as a properly designed electric fuse head with suitably hot burning pyrogen. You want a lot of heat generated in a small volume and
transferred to a small area (high temperature).
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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PHILOU Zrealone
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Quote: Originally posted by Bert ![](images/xpblue/lastpost.gif) |
Quote: |
but whats wrong with Zn+S ?
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Zn + S fuel is more like a slow flash powder than a rocket fuel, from my very limited experience. It MIGHT work as an igniter, but I know from
personal experience that the Copper or Manganese oxide + Al thermites have worked well as igniters, and that these can be regulated somewhat in burn
speed & ignition sensitivity by changing the Al powder particle size & shape.
If you experiment, let us know how it does.
(Edit)
I have just found some very fine Zn powder in my chemical storage, of a type used in anti corrosion paints. Some years back, a professional painter
had 50 lb. buckets of this that were punctured by a fork lift, he gave me the remaining material rather than try to salvage it and use it on a
government bridge painting project- It appears to be just fine, not oxidized or contaminated. I will try to make time for a small experiment-
[Edited on 5-3-2015 by Bert] |
Zn + S works as a rocket fuel because part of the Zn metal and Sulfur is vapourized by the reaction heat of Zn(s) + S(s) --> ZnS (s) and are
responsible of the rocket thrust.
The vapourized Zn burns with a long pale blueish flame in the open air at the exhaust of the rocket...somewhat bluer flame for sulfur.
Orange colour comes from the cardboard, glue, ceramic that contains sodium, calcium impurities...
Zn(g) + 1/2 O2(g) --> ZnO (s)
S2(g) + O2(g) --> SO(g) + SO2(g) + SO3(g)
It is quite fun but it requires a lot of (sometimes expensive) powderous Zn by weight and it last so short.
PH Z (PHILOU Zrealone)
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Fulmen
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It should be noted that An/S has a dodgy safety-record. IIRC it can be quite prone to static ignition, so do your research before playing.
As for ammonium nitrate propellants I think they are best suited for the experienced. While it is safe and has great performance at a low cost it
isn't the easiest to work with. For the beginner there is really nothing that compares to BP or KNO3/sugar.
We're not banging rocks together here. We know how to put a man back together.
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Bert
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I recall an amateur rocketry hobbyist getting severely burned by a Zinc Sulfur rocket fuel accident. He was carrying a plastic bag of leftover "micro
grain" fuel out to burn it off, and brushed the bag of fuel against a fence as he walked, which he believed drew a static spark through the powder.
His dog was walking with him, the dog got some very scorched fur too.
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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jock88
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There is some info. on Ammonpulver in COPAE.
Regarding Zn + S propellent I believe that the burn/reaction rate of the stuff is dependent on pressure in a strange way. When the pressure reaches a
certain value the reaction rate stops increasing. This makes it east to make rockets cause if the chamber can withstand this max. pressure then it is
impossible to have a CATO.
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ecos
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Quote: Originally posted by Hennig Brand ![](images/xpblue/lastpost.gif) | The electric match heads made of black powder bound in NC behave differently when lit than loose black powder or fibrous NC, they burn with a quick
flash that isn't too violent. What you have done may work, but it is very crude. A more consistent and focused heat/energy source would be more
desirable, such as a properly designed electric fuse head with suitably hot burning pyrogen. You want a lot of heat generated in a small volume and
transferred to a small area (high temperature). |
I started to get headache from the nitration process , thats why i stopped synthesizing NC or NG.
as stated before , they only solution to get KNO3 is from AN, it is headache in preparation since ammonia gas has sharp smell
Black powder is not easy thing to buy in my country ![:)](./images/smilies/smile.gif)
After making the metal wool and Al powder work , I would prepare a sample of 1.3 grams of thermite around it to look like this :
![](http://www.thefintels.com/aer/noi10.jpg)
I think this should work in the current time till i find a solution for KNO3 or BP
[Edited on 8-3-2015 by ecos]
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ecos
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Quote: Originally posted by Bert ![](images/xpblue/lastpost.gif) | I recall an amateur rocketry hobbyist getting severely burned by a Zinc Sulfur rocket fuel accident. He was carrying a plastic bag of leftover "micro
grain" fuel out to burn it off, and brushed the bag of fuel against a fence as he walked, which he believed drew a static spark through the powder.
His dog was walking with him, the dog got some very scorched fur too. |
I was not planning to use Zn/S as propellant , It was just an idea to use it to ignite instead of thermite.
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Bert
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Quote: | as stated before , they only solution to get KNO3 is from AN, it is headache in preparation since ammonia gas has sharp smell.
Black powder is not easy thing to buy in my country
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Probably best solution for KNO3 synthesis issue is a cheap fan and possibly a piece of cheap clothes dryer duct over reaction vessel,
discharging ammonia fumes elsewhere.
If BP can not be bought in your country, what is the legality of making your own?
Out of curiosity, do you know your local laws regarding an individual making black powder, various types of solid rocket fuel and related energetic
materials? It is better to know such things before the authorities bring them to your attention, especially when posting one's experiments online in
an open forum. Are there officially recognized hobby rocket makers or clubs in your country? If not, maybe you could START one?
USA is pretty easy on legal issues related to amateur rocketry, as long as nothing gets damaged and no one is hurt (and you don't piss off your
neighbors, local police, etc.)
But a kid from Scotland here recently spent some time arguing over being charged as a terrorist over making a KNO3 sugar rocket motor. It
was a ridiculous charge, but annoying, time consuming & expensive in lawyer time for his parents all the same.
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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