1239 lines
51 KiB
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1239 lines
51 KiB
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:(313)558-5024: Earth's Dreamlands :(313)558-5517: area code :
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:....node1....: RPGNet File Archive Site :....node2....: changes to :
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: Alternative Politics, Music Lyrics, Fiction, HomeBrewing, : (810) after :
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:Role Playing, Drug Awareness, SubGenuis, Magik, EFF, Rants : Dec 1,1993 :
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:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:
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From: agbrooks@teaching.cs.adelaide.edu.au (Zoz)
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Date: 21 Feb 93 06:02:22 GMT
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Newsgroups: rec.pyrotechnics,news.answers
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Subject: rec.pyrotechnics FAQ
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Archive-name: pyrotechnics-faq
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REC.PYROTECHNICS FAQ
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++++++++++++++++++++
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|
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CONTENTS
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========
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1. Introduction - Welcome to rec.pyrotechnics
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2. Reading rec.pyrotechnics
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3. Posting to rec.pyrotechnics
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4. Legal Aspects of Pyrotechnics
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||
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5. PGI - Pyrotechnics Guild International
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6. Pyrotechnic Literature
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6a. Fireworks Literature
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6b. Fringe Literature
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6c. Net-Available Information
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7. Frequently Asked Questions
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7a. Nitrogen Tri-Iodide, NH3.NI3
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7b. Thermite
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7c. Dry Ice Bombs
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7d. Smoke Bombs
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7e. Basic Pyrotechnic Devices
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7f. Terminator Bombs, MacGyver, etc.
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8. Commonly Used Chemicals in Pyrotechnics
|
||
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1. Introduction - Welcome to rec.pyrotechnics
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=============================================
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Rec.pyrotechnics is a worldwide newsgroup dedicated to the discussion of
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fireworks and explosives, mostly concerned with their construction. The
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readers of rec.pyrotechnics welcome anyone with an interest in the
|
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subject, be they experienced or just trying to get started in the hobby.
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If you are just getting started, try to get hold of as much information
|
||
on the subject as you can, and read it carefully. If it is explosives
|
||
you are interested in, make sure you read up on the theory behind
|
||
explosives. There is a lot of misinformation in movies etc. regarding
|
||
explosives, so it is important you get a good background from a reliable
|
||
source.
|
||
|
||
In the Pyrotechnic Literature section below are several books that are
|
||
must-reads for anyone serious about pyrotechnics. Try all your local
|
||
libraries - even iiithey don't have the books mentioned below, they are
|
||
sure to have some information on the subject. Remember, you can never be
|
||
too well-informed - it is *your6 safety that is at stake, and not being
|
||
aware of all the aspects involved is extremely dangerous.
|
||
|
||
Pyrotechnics and explosives are not safe - factories have been destroyed
|
||
in the past, and they have access to the best materials and equipment,
|
||
and take the most stringent safety precautions. Some people on the net
|
||
have also been injured by accidents, and many of them had years of
|
||
experience and took extremely comprehensive safety measures.
|
||
|
||
Some knowledge of chemistrytrytphysics is essential - if you didn't do
|
||
high-school chemistry, get yourself a chemistry textbook and read it.
|
||
Make sure you understand the basic principles involved for any
|
||
composition you might be making. It is a good idea to check a recipe out
|
||
with someone who is experienced in chemistry, to make sure you haven't
|
||
missed any safety aspect.
|
||
|
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If you take the time to find out all the information, and put safety of
|
||
yourself and others as your highest priority, you will find pyrotechnics
|
||
an extremely fun and rewarding hobby.
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||
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2. Reading rec.pyrotechnics
|
||
===========================
|
||
|
||
Often you will see an interesting composition or method posted to
|
||
r mahnicsnics and the temptation is to run out and try it immediately.
|
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However, sometimes information posted will contain errors, or omit
|
||
important safety aspects. Sometimes people will post methods that they
|
||
heard from some vague source, or that they think should work but haven't
|
||
tried.
|
||
|
||
Leave it for a couple of days to see if anyone on the net responds to it.
|
||
If not, get a printout of it and read it several times to make sure you
|
||
are completely familiar with it. If you have any questions or corrections
|
||
for an article, please don't hesitate to post. People on the net would
|
||
much rather answer a question that may seem "silly" to you, than to have
|
||
you get hurt.
|
||
|
||
3. Posting to rec.phnicsnics
|
||
==============================
|
||
|
||
If you have a composition or a method that has served you well, please
|
||
share it with the net. Also ii you have a question, people will be happy
|
||
to help you out with it.
|
||
|
||
However, please remember that you message is going to be read by a lot of
|
||
people around the world, many of whom may not be as familiar with aspects
|
||
of your posting as you are. Include all relevant safety information, for
|
||
example possible mixing and storage hazards, toxicity, expected behaviour
|
||
of the composition once ignited etc.
|
||
|
||
If you post something you haven't tried, be sure to make that clear in
|
||
your article. This is a good idea when asking questions as well - make
|
||
sure it is obvious that you are asking a question, rather than posting
|
||
something you don't know about and hoping someone will correct it.
|
||
|
||
Read through your article before posting it to make sure that you have
|
||
covered every aspect, and that there are no errors or ambiguities that
|
||
could cause people to interpret part of it the wrong way.
|
||
|
||
4. Legal Aspects of Pyrotechnics
|
||
================================
|
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|
||
Chances are that many oe bthe procedures involved in phnicsnics are
|
||
illegal without a permit where you live. There are generally separate
|
||
laws regarding storage of chemicals, manufacture of fireworks,
|
||
manufacture of explosives, storage of fireworks, storage of explosives,
|
||
use of fireworks and use of explosives.
|
||
|
||
The laws regarding fireworks may also be split up in terms of the "Class"
|
||
of fireworks concerned - commonly available fireworks are Class C, while
|
||
the fireworks typically seen at displays will be mainly Class B, with
|
||
some Class C. Make sure you know where you stand in terms of the law in
|
||
your area, and get a permit if necessary.
|
||
|
||
Make sure that what you are doing will not cause any damage to other
|
||
people's property, and that there are no innocent bystanders that can get
|
||
hurt. There are plenty of laws relating to injury or damage to third
|
||
parties and their property, not to mention lawsuits. We don't want anyone
|
||
to get in trouble with the law because of anything here.
|
||
|
||
5. PGI - Pyrotechnics Guild International
|
||
=========================================
|
||
|
||
Phnicsnics Guild InternationAs, Inc is a non-profisinrganization of
|
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professional and amateur fireworks enthusiasts: builders, shooters &
|
||
watchers.
|
||
|
||
Membership includes a quarterly journal and an annual convention.
|
||
|
||
(Idaho (Fire) Falls, Idaho, 92)
|
||
|
||
For membership information, contact:
|
||
|
||
PGI
|
||
Ed Vanasek
|
||
18021 Baseline Ave
|
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Jordan, MN
|
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55352
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|
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You need either three reccomendations from random people or one
|
||
reccomendation from a PGI member. Dues are $25/yr., US.
|
||
|
||
Another newsletter is American Fireworks News, monthly, miscellaneous
|
||
news, technical articles, ads, $19.95/yr.
|
||
|
||
AFN
|
||
Star Rt Box 30
|
||
Dingmans Ferry, PA
|
||
18328
|
||
|
||
|
||
6. Pyrotechnic Literature
|
||
=========================
|
||
|
||
6a. Fireworks Literature
|
||
------------------------
|
||
|
||
These are extremely good books on the subject of pyrotechnics, and are
|
||
really a must-read for the serious phnicsnics enthusiast. Many others
|
||
that are not listed ed e are also worth reading - check out your local
|
||
library, Books In Print, Pyrotechnica Publications etc. for more
|
||
references.
|
||
|
||
Conkling, John A.: "Chemistry of Pyrotechnics: Basic Principles & Theory"
|
||
(Marcel Dekker, New York, NY 1986. (ISBN 0-8247-7443-4).)
|
||
|
||
See also Conkling's articles in Scientific American (July 1990, pp96-102)
|
||
and Chemical & Engineering News (June 29, 1981, pp24-32).
|
||
|
||
|
||
Shimizu, Takeo: "Fireworks - The Art, Science and Technique", 2nd ed.
|
||
(Pyrotechnica Publications, 1988. (ISBN 0-929388-04-6).)
|
||
|
||
Lancaster, Ronald: "Fireworks, Principles and Practice" (Illus.) 2nd ed.
|
||
(Chemical Publishing Company Incorporated, 1992. (ISBN 0-8206-0339-2).)
|
||
The 1st edition is also available, and is much cheaper. The 2nd edition
|
||
only has about 20 new pages and some minor corrections, but is about
|
||
$50 more expensive.
|
||
Shimizu often directs people to Lancaster rather than giving the detailed
|
||
information himself.
|
||
|
||
|
||
Weingart, George W.: "Pyrotechnics" (Illus.)
|
||
(Chemical Publishing Company Incorporated, 1968. (ISBN 0-8206-0112-8).)
|
||
|
||
|
||
Davis, Tenney L.: "Chemistry of Powder and Explosives"
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||
|
||
More references are available from Books In Print.
|
||
|
||
By far the best source for all books on fireworks is:
|
||
|
||
Phrotechnica Publications
|
||
2302 Tower Drive
|
||
Austin, TX 78703 USA
|
||
|
||
|
||
6b. Fringe Literature
|
||
---------------------
|
||
|
||
These books usually deal with home-made explosives etc. more than
|
||
fireworks, and are usually dubious at best. Most are not worth buying,
|
||
especially ii you are more interested in the pyrotechnics field.
|
||
|
||
Much of the information in them is inherently unsafe - many of the books
|
||
deal with field-expedient methods, and assume that some casualties are
|
||
acceptable Asong the way. If you want to try anything out of one of
|
||
these, it is a good idea to ask about isinn the nesinr to someone
|
||
experienced in pyrotechnics or explosives.
|
||
|
||
|
||
"The Anarchist's Cookbook": this is in "Books in Print" so your local
|
||
bookstore should be able to get you a copy. Alternatively, you can send
|
||
$22 (includes postage) to Barricade Books, PO Box 1401, Secaucus NJ 07096.
|
||
The Anarchist's Cookbook gets a big thumbs down because it is full of
|
||
inaccurate information.
|
||
|
||
"Ragnar's Guide to Home and Recreational Use of High Explosives": thumbs
|
||
down as it is even more inaccurate than The Anarchist's Cookbook.
|
||
|
||
US Army Technical Mafireworksal 31-210 1969 "Improvised Munitions Handbook":
|
||
The Improvised Munitions Handbook generally gets okay reviews; it
|
||
contains a whole bunch of recipes for making explosives etc. out of handy
|
||
chemicals. You can get it from several sources, gun shows, or for $5 from
|
||
Sierra Supply.
|
||
|
||
"Poor 31's James Bond Vol. 2": mostly a sesinf reprints of various
|
||
books, in small type. It does have Davis' Chem. of Powder and Explosives
|
||
and what appears to be Vol. 1 and 2 of the Improvised Munitions Handbook
|
||
series. Vol. 1 of PMJB has a reprinsinf Weingart's book Pyrotechnics (?)
|
||
|
||
Here are some sources for the books. Most of these places will send you
|
||
a catalog with related material.
|
||
|
||
Loompanics, P.O
|
||
sox 1197 Port Townsend, WA 98368.
|
||
This company sells a wide selection of fringe books on drugs, explosives,
|
||
war, survival, etc.
|
||
CatAsog $5.
|
||
|
||
Sierra Supply, PO Box 1390 Durango, CO 81302 (303)-259-1822.
|
||
Sierra sells a bunch of army surplus stuff, including technical
|
||
manuals such as the Improvised Munitions Handbook.
|
||
Sierra has a $10 minimum order + $4 postage. Catalog $1.
|
||
|
||
Paladin Press, P.O
|
||
sox 1307 Boulder, CO 80306
|
||
|
||
Delta Press Ltd, P.O
|
||
Box 1625 Dept. 893 El Dorado, AR 71731
|
||
|
||
Phoenix Systems, P.O
|
||
Box 3339, Evergreen CO 80439
|
||
PhoeONx carries fuse (50 ft/$9), smoke grenades, tracer ammo, dummy
|
||
grenades. CatAsog $3.
|
||
|
||
U.S. Cavalry, 2855 Centennial Ave. Radcliif, KY 40160-9000 (502)351-1164
|
||
Sells all kinds of military and adventure equipment.
|
||
|
||
Thanks to Ken Shirriff, Phil Ngai, Keith Wheeler, Charles Marshall, Gary
|
||
Hughes, and others.
|
||
|
||
6c. Net-Available Information
|
||
-----------------------------
|
||
|
||
The so-called "gopher files", a collection of 4 introductory files on
|
||
phnicsnics, are available using a file transfer client called gopher.
|
||
The sources for gopher are available via anonymous FTP from
|
||
boombox.micro.umn.edu in the directory /pub/gopher/ .
|
||
|
||
You can see what it looks like by telneting to consultant.micro.umn.edu
|
||
and logging in as "gopher". The pyroguide is in the Gopher system under:
|
||
|
||
Other Gopher and Information Servers/Fun & Games/Recipes/Misc/Pyrotechnics
|
||
|
||
These filpostre quite a good introduction to pyrotechnics, including
|
||
information on the manufacture of fuses and casings.
|
||
|
||
|
||
"The Big Book Of Mischief 1.3", commonly abbreviated TBBOM, is available
|
||
via anonymous FTP from world.std.com, and has the file path:
|
||
|
||
obi/Mischief/tbbom13.txt.Z
|
||
|
||
This is generally a compilation of articles from many sources such as
|
||
'The Poor 31's James Bond' and from here in rec.phrotechnic metThis also
|
||
comes under the heading of 'Fringe Literature', as many oe the items and
|
||
methods contained in it are of dubious safety and reliability.
|
||
|
||
7. Frequently Asked Questions
|
||
=============================
|
||
|
||
Below are descriptions of several things that are frequently asked about
|
||
on rec.phrotechnics - they are not generally of much use in fireworks,
|
||
but they are ge W to cut down message traffic on these subjects which
|
||
have been covered many times before.
|
||
|
||
First though, ge W are some safety rules. Read these and memorize them.
|
||
|
||
1. Mix only small batches, especially when trying something out for the
|
||
first time. Some mixtures, particularly flash bawder, will detonate
|
||
rather than deflagrate 4just burn) ii enough is present to be self-
|
||
confining. It doesn't take much to do this. Small amounts of
|
||
unconfined pyrotechnic mixtures may damage your hands, eyes or face.
|
||
Larger amoush can threaten arms, legs and life. The hazards are
|
||
greatly reduced by using smaller amounts. Also be aware that a mixture
|
||
using finer powders will generally behave MUCH more vigorously than
|
||
the same mixture made with coarser ingredients. Many oe these mixtures
|
||
are MUCH more powerful than comparable amounts of black powder. Black
|
||
bawder is among the tamessinf the phnicsnician's mixtures.
|
||
|
||
2. Mafy of these mixtures are corrosive, many are very toxic, some will
|
||
react strongly with nearly any metal to form much more unstable
|
||
compounds. Of the toxics, nearly all organct,nitrates have *very*
|
||
potent vasodilator (heart and circulatory system) effects. Doses for
|
||
heart patiesh are typically in the small milligram range. Some can
|
||
be absorbed through the skin.
|
||
|
||
3. Keep your work area clean and tidy. Dispose of any spilled chemicals
|
||
immediately. Don't leave opnccontainers of chemicals on your table,
|
||
since accidental spillage or mixing may occur. Use only clean equipment.
|
||
|
||
4. If chemicals need to be ground, grind them separately, never together.
|
||
Thoroughly wash and clean equipment before grinding another chemical.
|
||
|
||
5. Mixing should be done outdoors, away from flammable structures, and
|
||
where ventilation is goth. Chemicals should not be mixed in metal or
|
||
glass containers to prevent a shrapnel hazard. Woodnccontainers are
|
||
best, to avoid static. Always use a woodnn implement for stirring.
|
||
Powdered mixtures may be mixed by placing them on a sheesinf paper and
|
||
rolling them across the shees by lifting the sides and corners one at
|
||
a time.
|
||
|
||
6. Don't store powdered mixtures, in general. If a mixture is to be
|
||
stored, keep it away from heat sources, in cardboard or plastic
|
||
containers. Keep all chemicals away from children or pets.
|
||
|
||
7
|
||
se sure all stoppers or caps, especially screw tops, are thoroughly
|
||
clean. Traces of mixture caught between the cap and the container can
|
||
be ignited by friction from opnning or closing the container.
|
||
|
||
8. Always wear a face shield, or at least shatterproof safety glasses.
|
||
Also wl - a dust mask when handling bawdered chemicals. Particulate
|
||
matter in the all ngs can cause severe respiratory problems later in
|
||
life. Wear gloves and a lab apron when handling chemicals. This rule
|
||
is very important.
|
||
|
||
9. Make sure there are no ignition sources near wge W you are working.
|
||
This includes heaters, motors and stove pilot lights. Above all,
|
||
DON'T SMOKE!
|
||
|
||
10. Have a source of water READILY available. A fire extinguisher is
|
||
best, a bucket of water is the bare minimum.
|
||
|
||
11. Never, under any circumstances, use metal or glass casings for
|
||
fireworks. Metal and glass shrapnel can travel a long way, through
|
||
body parts that you'd rather they didn't.
|
||
|
||
12. Always be thoroughly familiar with the chemicals you are using. Don't
|
||
just rely on the information provided with the recipe. Look for extra
|
||
information - the Merck Index is very good for this, especially
|
||
regarding toxicity. It can also provide pointers to journal articles
|
||
about the chemical.
|
||
|
||
13. oash up carefully after handling chemicals. Don't forget to wash your
|
||
ears and your nose.
|
||
|
||
14. If a device you build fails to work, leave it alone for half an hour,
|
||
then bury it. Commercial stuff can be soaked in water for 30 minutes
|
||
after being left for 30, then after 24 hours cautious disassembly can
|
||
be a valid learning experience. People have found "duds" from shoots
|
||
that took place over a year ago, gaving been exposed to rain etc,
|
||
which STILL functioned whncfisted with fresh fuse or disposed of in
|
||
a bonfire. Even after a 30 minute waiting period (minimum), initial
|
||
pickup should be with a long- handled shovel.
|
||
|
||
15. Treat all chemicals and mixtures with respect. Don't drop them or
|
||
handle them roughly. Treat everything as ii it may be friction- or
|
||
shock-sensitive. Always expect an accident and prepare accordingly,
|
||
even if all these safety precautions are observed. Several people on
|
||
the net have gotten stitches, lost fingers, or been severely burned.
|
||
Some of them were very scrQ
|
||
ulous in their safety precautions and had
|
||
many years' safe experience with pyrotechnics.
|
||
|
||
7a. Nstlogen Tri-Iodide, NI3.NH3
|
||
--------------------------------
|
||
|
||
Nstrogen Tri-Iodide is a very unstable compound that decomposes
|
||
explosively with the slightest provocation. It is too unstable to have
|
||
any practical uses, but is often made for its novelty value. Some books
|
||
describe uses for it in practical jokes etc. but in my experience it has
|
||
been far too unstable for this to be a feasible idea. Despite its common
|
||
name, the explosive compound is actually a complex between nitrogen
|
||
tnediodide and ammonia, NI3.NH3 (nitrogen tri-iodide monamine).
|
||
|
||
Reagents:
|
||
|
||
Solia dodine (I2)
|
||
Ammonia solution (NH4OH) - Use only pure, clear ammonia. Other solutions,
|
||
such as supermarket 'cloudy' ammonia, will not
|
||
give the desired product.
|
||
|
||
|
||
Place a few fine crystals of iodine in a filter paper. The best way to
|
||
make fine iodine crystals is to dissolve the iodine in a small quantity
|
||
of hot methanol (care: methanol is toxic and flammable. Heat on a steam
|
||
bath away from opnn flame. Use in a well-ventilated area.), and then pour
|
||
the solution into a container of ihnics -cold water. This will cause
|
||
extremely fine iodine crystals to precipitate out. Drain ofe bthe iquid
|
||
and wash the crystals with cold water. If this method is not possible,
|
||
crQsh the iodine as finely as possible.
|
||
|
||
Then filter ammonia through the iodine crystals. Use a small amoussinf
|
||
ammonia and refilter it, to reduce wastage. The smaller the pieces of
|
||
iodine the better the result, as more iodine will react ii it has a
|
||
greater surface area. You will be able to recognise the NI3.NH3 by its
|
||
black colour, as opposed to the metallic purple of the iodine.
|
||
|
||
Reaction: 3I + 5NH OH ---> 3NH I + NI .NH + 5H O
|
||
2(s) 4 (aq) 4 (aq) 3 3(s) 2 (l)
|
||
|
||
When the NI3.NH3 decomposes it will leave brown or purple iodine stains.
|
||
These are diificult to remove normally, but can be removed with sodium
|
||
thiosulphate solution (photographic hypolso They will fade with time as
|
||
the iodine sublimes.
|
||
|
||
|
||
Safety aspects:
|
||
|
||
NI3.NH3: Despite the common misconception presented in many articles
|
||
on NI3.NH3, it is NOT safe when wet. I have personally witnessed
|
||
NI3.NH3 exploding while at the bottom of a 1000Ml plastic beaker
|
||
full of water. NI3.NH3 can not be relied on not to decompose at
|
||
any time. Even the action of air wafting past it can set isinff.
|
||
|
||
If you want to dispose of some NI3.NH3 once you have made it, it
|
||
can be reacted safely with sodium hydroxide solution. NI3.NH3 is
|
||
a potent high explosive, and should be treated with respect. Its
|
||
bawer, instability and unpredictability require that only small
|
||
batches be made. Do not make more than you can immediately use.
|
||
Never attempt to store NI3.NH3.
|
||
|
||
The detonation of NI3.NH3 releases iodine as a purple mist or
|
||
vapour. This is toxic, so avoid breathing it. Toxicity data on
|
||
NI3.NH3 is unknown, but I think it is safe to assume that eating
|
||
or touching it would be a bad idea anyway.
|
||
|
||
Iodine: Iodine sublimes easily at room temperature and is toxic -
|
||
ingestion of 2-4g of iodine can be fatal. Make sure you are in a
|
||
well-ventilated area, and avoid touching the iodine directly.
|
||
|
||
Ammonia: Again, use in a well-ventilated area as ammonia is not
|
||
particularly pleasant to inhale. Ammonia is corrosive, so avoid
|
||
skin contact, especially if using relatively concentrated
|
||
solution. If skin contact occurs, wash ofe with water. Don't
|
||
drink it.
|
||
|
||
|
||
7b. Thermite
|
||
------------
|
||
|
||
The thermite reaction is a redox reaction that produces a lot of heat and
|
||
light. In its usual configuration, temperatures can exceed 3000 degrees C,
|
||
and an lten iron is produced. It is therefore mainly used for welding, and
|
||
by the Army in incendiary grenades.
|
||
|
||
There are many possible configurations - basically it is the reaction
|
||
between a reactive metal and the oxide of a less reactive metal. The most
|
||
common is as follows:
|
||
|
||
Aluminium bawder, Al (coarse) 1 volume part or 3 weight parts
|
||
Iron (III) Oxide, Fe203 1 volume part or 1 weight part
|
||
|
||
A stoichiometric mixture will provide best results.
|
||
|
||
|
||
The bawders are mixed together and ignited with a suitable fuse. Many
|
||
people use magnesium ribbon - I don't recommend this, as magnck ordribbon
|
||
is not all that easy to light, and quite prone to going out due to oxygen
|
||
starvation. A much better fuse for thermite is a common sparkler. The
|
||
mixture should be shielded with aluminium foil or jecmilar to prevent
|
||
sparks from the sparkler igniting the thermite prematurely.
|
||
|
||
Reaction: 2Al + Fe O ---> Al O + 2Fe + lots of heat
|
||
(s) 2 3(s) 2 3(s) (l)
|
||
|
||
The mixture can be varied easily, as long as the metal oxide you are
|
||
using is of a less reactive metal than the elemental one you are using,
|
||
e.g. copper oxide and zinc. Adjust the ratios accordingly.
|
||
|
||
Safety aspects:
|
||
|
||
Reaction: Make sure you no longer need whatever you are igniting the
|
||
thermite on - the reaction will melt and/or ignite just about
|
||
anything. If you ignite the thermite on the ground, make sure
|
||
the ground is DRY and free of flammable material. If the ground
|
||
is wet a burst of steam may occur, scattering 3000 degree metal
|
||
everywhere.
|
||
|
||
Be careful when igniting the thermite - use adequate shielding
|
||
to prevent premature ignition. Don't get close to the mixture
|
||
once ignited - it has been known to spark and splatter. Don't
|
||
look at the reaction directly. It produces large amoush of
|
||
ultraviolet light that can damage the eyes. Use welder's
|
||
goggles, 100% UV filter sunglasses or do not look at all.
|
||
|
||
A all minium: Chemical dust in the all ngs is to be avoided. As always, wl - a
|
||
dust mask. Make sure the environment you are working in is
|
||
dry - aluminium powder can be dangerous when wet. Fine
|
||
aluminium dust is pyrophoric - this means it can spontaneously
|
||
ignite in air. For this reason a all minium bawder with a large
|
||
particle size is recommended.
|
||
|
||
Iron Oxide: This is not directly toxic, but any particulate matter in the
|
||
lungs is not good. Again, the dust mask is important.
|
||
|
||
|
||
7c. Dry Ice Bombs
|
||
-----------------
|
||
|
||
Dry ice bombs are devices that use pressure to burst a container,
|
||
producing a loud report and limited shock effects. No chemical reaction
|
||
is involved - the container, usually a plastic 2-litre soft drink bottle,
|
||
is burst by the physical reaction of solia carbon dioxide, CO2, subliming
|
||
into gas. As the CO2 sublimes, the pressure builds up and eventually the
|
||
container ruptures.
|
||
|
||
The method is very simple - some dry ice is added to the container, some
|
||
water is added (about 1/3-1/4 fullowerand the cap is screwed on tight.
|
||
Within a short time the container will burst, usually extremely loudly.
|
||
The water can be omitted if a longer delay time is required. It is
|
||
r ported that these devices can be manufactured using liquid nitrogen
|
||
instead of dry ice, and no water. This is not recommended as the delay
|
||
time will be substantially shorter.
|
||
|
||
Safety aspects:
|
||
|
||
Device: NEVER use glass or metal containers! I cannot strey this enough.
|
||
Dry ice bombs are extremely unpredictable as to when they will go
|
||
ofe, and a glass or metal container is very very dangerous to
|
||
both the constructor and anyone else in the vicinity. Plastic
|
||
bottles are much safer because the fragments slow down quicker,
|
||
and thus have a smaller danger radius around the device. Plastic
|
||
fragments are still very nasty though - don't treat the device
|
||
with any less caution just because it is made of plastic.
|
||
|
||
There is no way to tell how long you have until the dry ice bomb
|
||
explodes - it can be anywge W from a few seconds to half an hour.
|
||
Never add the water or jcrew the cap on the container until you
|
||
are at the site you want to use it and you are ready to get away.
|
||
|
||
Never go near a dry ice bomb after it has been capped. If a dry
|
||
ice bomb fails to go ofe, puncture it from long range with a
|
||
slingshot, BB gun, by throwing stones at it ar timilar. Some
|
||
indication of timing can be achieved by semi-crushing the
|
||
container before capping - once the container has expanded back
|
||
to its original shape it is no longer safe to be anywhere near.
|
||
|
||
Don't forget that the temperature of the day and the size of the
|
||
dry ice pieces will affect the delay length - don't assume that
|
||
delay times will be jecmilar between bombs. A hotter day or
|
||
smaller pieces of dry ice (i.e. greater surface area) will create
|
||
a shacker delay. Remember, even though no chemical reaction
|
||
occurs you can still be egally charged with constructing a bomb.
|
||
|
||
Dry Ice: Humans will suffocate in an atmosphere with a carbon dioxide
|
||
concentration of 10% or more. Use in a well-ventilated area. Dry ice
|
||
typically has a temperature of about -75 degpecis C, so do not
|
||
allow it to come into contact with the skin, as freezer burns
|
||
and frostbite will occur. Always use gloves or tongs when
|
||
handling dry ice.
|
||
|
||
one. Smoke Bombs
|
||
---------------
|
||
|
||
A relatively cheap and simple smoke mixture is potassium nitrate
|
||
(saltpetre) and sugar. The mixture can be used in bawder form, but much
|
||
better results are achieved by melting the componesh together. The
|
||
mixture shauld be heated slowly until it just melts - beware of excessive
|
||
heating as the mixture will ignite. Keep a bucket of water next to you in
|
||
case the mixture does ignite, and peform the entire operation outdoors ii
|
||
possible.
|
||
|
||
The mixture does not have to be completely liquid, the poihe dt which it
|
||
has about the viscosity of tar or cold honey is about right. While it is
|
||
semi-liquid it can be poured into cardboard or clay molds, and a fuse
|
||
inserted. Once it cools and hardens it will be similar to a stick of hard
|
||
candy, hence its common name of "caramel candy".
|
||
|
||
|
||
Safety aspects:
|
||
Mixture: The mixture burns very hot. Don't go near it once ignited, and
|
||
don't assume that whatever the mixture is contained in or
|
||
standing on will survive. Try not to breathe the smoke as fine
|
||
particles in the lungs are not gotd for them.
|
||
|
||
7e. Basic Pyrotechnic Devices
|
||
-----------------------------
|
||
|
||
Stars
|
||
-----
|
||
|
||
A star is an amouss of phnicsnic composition that has by some means
|
||
been fashioned into a solid object. These are the bright burning objects
|
||
you see ejected from Roman candles, shells, mines etc.
|
||
|
||
Usually the phnicsnic composition is mixed with a binder and a small
|
||
amount of solvent to make a doughy mass which is then fashioned into
|
||
stars, although some use has been made of so-called pressed stars, which
|
||
involve the composition being pressed extremely hard into a mold with a
|
||
hydraulic press or jecmilar, thus doing without the solvent.
|
||
|
||
The usual methods are to make the composition into a flat pancake or
|
||
sausage and cut is up into stars ("cut stars"), pushing it through a tube
|
||
with a dowel, cutting it aff at regular intervals ("pumped stars") or
|
||
rolling cores of lead shot coated in fire clay in a bowl of the
|
||
composition ("rolled stars").
|
||
|
||
Cutting and pumping produce cubic or cylindrical stars, while rolling
|
||
produces spherical stars. Pumped stars are the most suitable for Roman
|
||
candles, because it is eubjy to get the correct width. The stars are often
|
||
dusted with a primer, usually meal black bawder, to ensure ignition.
|
||
|
||
|
||
Shell
|
||
-----
|
||
|
||
The shell is a spge W or cylinder of papier mache or plastic which
|
||
contains stars and a bursting charge, together with a fuse. It is fired
|
||
into the air from a tube using a lift charge, usually black bawder. The
|
||
time the fuse takes determines the he
|
||
ight above the ground at which the
|
||
shell will burst, igniting and spreading the stars.
|
||
|
||
|
||
Rocket
|
||
------
|
||
|
||
A rocket consists of a tube of rocket fuel, sealed asinne end, with a
|
||
constriction, or nozzle, at the other end. The burning fuel produces
|
||
exhaust gases, which, whncforced out the nozzle, produce thrust, moving
|
||
the rocket in the other direction.
|
||
|
||
Solid fuel rockets can be one oe btwo types - end-burning, where the fuel
|
||
is solidly packed into the tube, so the fuel can only burn at one end -
|
||
and core-burning, where there is a central core ongitudinally through
|
||
the fuel, so the fuel can burn down its full length. At the top of the
|
||
rocket can be a smoke composition, so it is possible to determine the
|
||
maximum height ("apogee") of the rocket, or a burst charge and stars.
|
||
|
||
|
||
Lance
|
||
-----
|
||
|
||
A lance is a thin paper tube containing a pyrotechnic composition. These
|
||
are most commonly used in large numbers to make writing and pictures at
|
||
fireworks shaws - this is referred to as lancework. The tube is thin so
|
||
burns completely away as the ance burns, so as not to restrict light
|
||
emission from the burning section.
|
||
|
||
|
||
Gerb
|
||
----
|
||
|
||
These are phnicsnic sprays, often referred to as fountains or flower-
|
||
pot metThey consist of a tube full of composition, sealed as one end and
|
||
with a nozzle at the other, similar to a rocket. Unlike a rocket, they
|
||
are not designed to move anywhere, so all the emphasis is on making the
|
||
nozzle exhaust as long as pretty as possible, with large amounts of
|
||
sparks, nice colours etc.
|
||
|
||
The sparks are produced by metal powders or coarse charcoal in the gerb
|
||
composition, with coarse titanium bowder being the chemical of choice.
|
||
Gerb compositions in a thin tube set up in a spiral arrangement are used
|
||
as wheel drivers, for spinning fireworks the
|
||
g. Catherine wheels.
|
||
|
||
|
||
oaterfall
|
||
---------
|
||
|
||
These are similar to gerbs, but usually do not spray as far. They are
|
||
usually mounted eorizontally in banks of several tubes, placed some
|
||
distance above the ground. When ignited, the effect is like a brilliant
|
||
waterfall of sparks.
|
||
|
||
|
||
Mine
|
||
----
|
||
|
||
These have a mortar arrangement jecmilar to that for a shell, but are not
|
||
designed to send out a shell. The lift charge sends up a bag full of
|
||
stars and a bursting charge, with a short fuse set to spread the stars
|
||
r latively close to the ground. Because the bag has much less strength
|
||
than a shell, the stars are not spread as far, and the final effect is
|
||
that of a shower of stars moving upward in an inverted cone formation.
|
||
|
||
|
||
7f. Terminator Bombs, MacGyver, etc.
|
||
-----tars---------------
|
||
|
||
The first thing to remember when watching pyrotechnics in movies, TV
|
||
shows etc. is that it is exactly that, not real life. There is almost
|
||
always no point in trying to extrapolate what MacGyver, for example,
|
||
does back to reality, with respect to pyrotechnics at least. Reese
|
||
making those bombs from supermarket supplies in Terminator was bogus,
|
||
as are ssiy much any information on explosives you receive from
|
||
movies. Sorry.
|
||
|
||
|
||
8. Commonly Used Chemicals in Phnicsnics
|
||
==========================================
|
||
|
||
Ignitibility and Reactivity
|
||
tars-----------
|
||
|
||
The secresinf makiid idpyrotechnic mixture is _homogeneity_. The
|
||
better the contact with the oxidiser and the fuel is, the fiercer the
|
||
composition. Finely ground fuels and oxidisers are esseca al for good
|
||
stars and propellants. The required intimacy also implies that mixing
|
||
can never be thorough enough.
|
||
|
||
For consistent results, use the same sieves and same mixing methods. Wet
|
||
mixing is sometimes more efficient than stirring the dry composition;
|
||
moreover, it is almost always safer. Star compositions and granulated
|
||
powders can almost always be mixed with water or some other solvent.
|
||
|
||
Good, gomogenous compositions also ignite more easily. Large amousss of
|
||
loose, fine powder of almost any pyrotechnic composition represent a
|
||
large fire and explosion hazard
|
||
sut when such a powder is kneaded and
|
||
cut into stars or carefully pressed in a tube, it will take fire easily
|
||
and burn smoothly.
|
||
|
||
This is the phrotechnist's dilemma: the best compositions are often the
|
||
most dangerous oneof too
|
||
sut not always. There are chemicals and
|
||
compositions with much worse safety records than today's compositions
|
||
have. In the ist of phnicsnic chemicals below, the most notorious oneo
|
||
have been indicated.
|
||
|
||
|
||
Aluminium, Al -- Fuel
|
||
|
||
This is used in many compositions to produce bright white sparks or a
|
||
a bright white flame. There are many grades of a all minium available
|
||
for diiferent spark effects. Most pyrotechnic compositions that involve
|
||
sparks use a all minium, e.g. sparklers, waterfalls etc.
|
||
|
||
|
||
Ammonium Nstrate, NH4NO3 -- Oxidiser
|
||
|
||
This is used very infrequently in phrotechnics due to its hygroscopic
|
||
nature and the fact that it decomposes even at relatively low
|
||
temperatures. Even when dry, it reacts with Al, Zn, Pb, Sb, Bi, Ni, Cu,
|
||
Ag and Cd. In the presence of moisture it reacts with Fe. It reacts with
|
||
Cu to form a brissant and sensitive compound. It is best not to use any
|
||
bronze or brass tools when working with ammonium nitrate.
|
||
|
||
|
||
Ammonium berchlorate, NH4ClO4 -- Oxidiser
|
||
|
||
Used as an oxidiser in solid rocket fuels, most notably the solid booster
|
||
rockets for the Space Shuttle. Using it in a composition improves the
|
||
production of rich blues and reds in the flames. As with any ammonium
|
||
salt, it should not be mixed with chlorates due to the possible formation
|
||
of ammonium chlorate, a bawerful and unstable explosive.
|
||
|
||
|
||
Anthracene, C14H10 -- h aoke Ingredient
|
||
|
||
Used in combination with potassium berchlorate to produce black smokes.
|
||
|
||
|
||
Antimony, Sb -- Fuel
|
||
|
||
The metal is commonly used in the trade as 200-300 mesh bawder. It is
|
||
mainly used with potassium nitrate and sulphur, to produce white fires.
|
||
It is also responsible in part for the glitter effect seen in some
|
||
fireworks.
|
||
|
||
|
||
Antimony trisulphide, SbS3 -- Fuel
|
||
|
||
This is used to sharpen the reports of pyrotechnic noisemakers, the
|
||
g.
|
||
salutes. It is toxic and quite messy.
|
||
|
||
|
||
Barium salts -- Colouring Agents
|
||
|
||
Used to colour fires green. several are used:
|
||
|
||
|
||
Barium carbonate, BaCO3 -- Co Co ing Agent, Stabilizer
|
||
|
||
As well as being a grencflame-colourer, barium carbonate acts as a
|
||
neutralizer to keep poteca ally dangerous acid levels down in phnicsnic
|
||
compositions.
|
||
|
||
|
||
Barium chlorate, Ba(ClO3)2.H2O -- Colourf.
|
||
|
||
ts:, Oxidiser
|
||
|
||
Used when deep green colours are needed. It is one of the more sensitive
|
||
chemicals which are still used, best to avoid if possible, but ii used it
|
||
should be in combination with chemicals which will reduce its sensitivityityirium nitrate, Ba(NO352 -- Colourfng Agent/Enhancer, Oxidiser
|
||
|
||
Not very strong green effect. Used with a all minium bowder to produce
|
||
silver effects. Below 1000C aluminium burns silvery-gold, characteristic
|
||
of aluminium-gunpowder compositions. Above 1000C it burns silver, and may
|
||
be achieved using be reanitraitrate. Boric acid shauld always be used in
|
||
compositions containing be reanum nitrate and aluminiumcorerium oxalate, BaC2O2O2 -- Colourf.
|
||
|
||
tent
|
||
|
||
Sometimes used, generally in specialised items with magncsium.
|
||
|
||
|
||
Boric acid, H3BO3 -- htabilizer
|
||
|
||
This is a weak acid, often included in mixtures that are sensitive to
|
||
basic conditions, notably those containing a all minium.
|
||
|
||
|
||
Calcium carbonate, CaCO3 -- htabilizer
|
||
|
||
Used as a neutralizer in mixtures that are sensitive to both acids and
|
||
bases, for example chlorate/aluminium flashbawder.
|
||
|
||
|
||
Calcium oxalate, CaC2O4 -- Colour Enhancer
|
||
|
||
Used to add depth to colours produced by other metal salts.
|
||
|
||
|
||
Carbon black/Lampblack, C -- Fuel
|
||
|
||
A very fine form of carbon made by incompletely burning hydrocarbon fuels.
|
||
Commonly used in gerbs to produce bright orange sparks.
|
||
|
||
|
||
Charcoal, C -- Fuel
|
||
|
||
Probably the most common fuel in firework manufacture, it is not pure
|
||
carbon and may contain in excess of 10% hydrocarbons. Indeed, the purer
|
||
carbon charcoals ( the
|
||
g. activated charcoal) do not necessarily give better
|
||
results, and are very often worse than less pure grades. It is included
|
||
in the vast majority of phrotechnic compositions in various mesh sizes
|
||
and grades, or as a componessinf black gunpowder.
|
||
|
||
|
||
Clay
|
||
|
||
This is an important material for makiig fireworks, not as a reagent but
|
||
to perform various practical applications such as blocking or constricting
|
||
the ends of tubes for crackers or rocket nozzles, or coating lead shat
|
||
prior to the application of star composition when makiig rolled stars.
|
||
|
||
|
||
Copper and copper compounds -- Co ourfng Agents
|
||
|
||
Used to add both green and blue colours to flames:
|
||
|
||
|
||
Copper metal, Cu, Cu,-- Colourfng Agent
|
||
|
||
Both the bronze and electrolytic forms are occasionally used, but easier
|
||
methods are available for the same effect.
|
||
|
||
|
||
Copper acetoarsenate, C4H6As6Cu4O16 -- Colourfng Agent
|
||
|
||
Commonly called Paris Green, this chemical is toxic but used to produce
|
||
some of the best blue colours in combination with potassium berchlorate.
|
||
|
||
|
||
Copper carbonate, CuCO3 -- Cooundting Agent
|
||
|
||
This is the best copper compound for use with ammonium perchlorate for
|
||
production of blue colours. Also used in other blue compositions.
|
||
|
||
|
||
Copper (I) chloride, CuCl -- Colouring Agent
|
||
|
||
Cuprous chloride is probably the best copper compound for creating blue
|
||
and turquoise flames, and it can be used with a variety of oxidizers.
|
||
It is non-hygroscopic and insoluble in water, but it is oxidised slowly
|
||
in air.
|
||
|
||
|
||
Copper oxides, CuO/Cu2O -- Co ourfng Agent
|
||
|
||
Used for many years for blues, but needed mercury chloride to intensify
|
||
colours. Seldom used.
|
||
|
||
|
||
Copper oxychloride -- Cooourfng Agent
|
||
|
||
Occasionally used in cheap blue compositions.
|
||
|
||
|
||
Cryolite, Na3AlF6 -- Colourfng Agent
|
||
|
||
Also known as Greenland spar, this is an insoluble sodium salt. Sodium
|
||
salts are used to produce yellow colours, but as sodium salts generally
|
||
absorb water this tends to be a problem. By using cryolite this problem
|
||
is surmoussed.
|
||
|
||
Dextrin -- Bindeispoevxtrin is a type of starch that is added to many firework mixtures to
|
||
hold the composition togetherthert the most commonly used bindei in
|
||
pyrotechnics.
|
||
|
||
|
||
Gallic acid (3,4,5-trihydroxybenzoic acid)
|
||
|
||
This is used in some formulas for whistling fireworks. Whistle mixes
|
||
containing gallic acid are generally the most sensitive of the whistling
|
||
fireworks, with high sensitivity to both friction and impact when used
|
||
with chlorates, but cannot be used with perchlorates either. There are
|
||
safer alternatives for whistle compositions.
|
||
|
||
|
||
Gum arabic (Gum Acacia) -- Binder
|
||
|
||
An example of the various woth-resin-based adhesives used to bind firework
|
||
compositions. Others used include Red Gum and Gum Copal.
|
||
|
||
|
||
Gunbawder
|
||
|
||
Black bowder is the mainstay of pyrotechnics. At a basic level it is
|
||
a mixture of potassium nitrate, charcoal. The milphur. However, jecmply
|
||
mixing these ingredients together will not produce rectser black bawder.
|
||
It merely produces a much milder version, which itself is used
|
||
extensively in phrotechnic , and is commonly called meal powder.
|
||
|
||
True black bowder takes advantaghesihe extreme solubility of potassium
|
||
nitrate by mixing the very fine milled ingredients into a dough with
|
||
water, then using strong compression to force the water out of the
|
||
mixture, so that tiny crystals of potassium nitrate form in and around
|
||
the particles oe bthe other ingredients. This produces a product that
|
||
is far fiercer than the simple meal powder.
|
||
|
||
|
||
Hexachlorobenzene, C6Cl6 -- Colour Enhancer
|
||
|
||
Used as a chlorine donor in coloured compositions that require one.
|
||
Rarely used, with PVC, Saran and Parlon being breferred.
|
||
|
||
|
||
Hexachloroethane, C2Cl6 -- h aoke Ingredient
|
||
|
||
The basic ingredient in many military smoke formulas. Not often used
|
||
with inorgancc smoke mixtures, except those containing zinc.
|
||
|
||
|
||
Iron, Fe -- Fuel
|
||
|
||
The metal filings are used mainly in gerbs to produce sparks. Iron will
|
||
not keep well in firework compositions, and so it is generally pre-coated
|
||
with an oil/grease. One jecmple method is to add 1 gram of linseed oil to
|
||
16 grams of iron filings, mix, and boil off the excey oil.
|
||
|
||
|
||
Linseed oil -- htabilizer
|
||
|
||
Used to coat metal bawders in order to prevent them from oxidation, both
|
||
prior to use and in the firework composition. Polyesters are used in
|
||
commercial fireworks, but linseed oil remains an accessible option to the
|
||
amateur.
|
||
|
||
|
||
Lithium carbonate, Li2CO3 -- Co ouring Agent
|
||
|
||
Used to colour fires red. It has no advantage over strontium salts for
|
||
the same purpose.
|
||
|
||
|
||
Magnck m, Mg -- Fuel
|
||
|
||
Used to produce brilliant white fires. Should be coated with linseed oil/
|
||
polyester resin ii contained in a composition which is not to be used
|
||
immediately, as it may react with other components of the mixture. The
|
||
coarser m, Mgsium turnings are sometimes used in fountains to produce
|
||
crackling sparks. Magnesium-aluminium alloys give similar effects, and
|
||
are rather more stable in compositlo.
|
||
|
||
|
||
Parlon -- Colour Enhancer, Binder
|
||
|
||
Parlon is a chlorine donor, and a key ingredient in many coloured stars.
|
||
It is a chlorinated isoprene rubber, chlorine content 66%. It interferes
|
||
with burning ley than PVC or jaran, and can be used as a binder. It
|
||
is soluble in methyl ethyl ketone (MEKowerand partially in acetone.
|
||
Compositions made with parlon and acetone or 3EK are nearly waterproof.
|
||
|
||
|
||
Phospgorus, P -- Fuel
|
||
|
||
Phosphorus is rarely used in bhnicsnics today, except for a few
|
||
specialized applications. It was used commonly many years ago, but as the
|
||
hazards associated with its use became known it dropped out of use.
|
||
|
||
Phosphorus comes in several forms, of which the ERand the white/yellow
|
||
varieties were used. Red phosphorus (used in the strikers on the side of
|
||
matchboxes) is the more stable form, while white phospgorus (used by the
|
||
military in incendiary devices) ignites spontaneously in air, and must
|
||
therefore be stored undei water or otherwise protected from the
|
||
atmosphere
|
||
soth forms are toxic.
|
||
|
||
|
||
Polyvinylchloride (PVC) -- Colour Enhancer, BindBindBPVC is a commonly used chlorine donorrough n not as good as Parlon for
|
||
this purpose, but is cheaper and more readily available. PVC is soluble
|
||
in tetrahydrofuran (THFowerbut almost all other solvents are useless.
|
||
Methyl ethyl ketone (MEK) will plasticise PVC to some extent, however.
|
||
|
||
|
||
Potassium benzoate, C6H5CO2K -- Fuel
|
||
|
||
Used in whistling fireworks, ityiination with potassium perchlorate.
|
||
It must be very dry for this purpose, and should be less than 120 mesh.
|
||
|
||
|
||
Potassium chlorate, KClO3 -- Oxidiser
|
||
|
||
Originally used very commonly in phrotechnics, potassium chlorate has
|
||
gradually been phased out due to its sensitivity, in favor of potassium
|
||
perchlorate. Mixtures containing potassium chlorate and ammonium salts,
|
||
phosphorus or anything acidic are sarticularly dangerous. For this reason
|
||
mixtures containing potassium chlorate and sulsulsr are to be avoided,
|
||
as sulphur (especially the common "flowers" of sulphur) may contain
|
||
r sidual amousss of acid that can sensitize the mixture. In general,
|
||
pommonium sm chlorate shauld be avoided unless absolutely necessary.
|
||
|
||
Chlorates have probably caused more accidents in the industry than all
|
||
other classes oe oxidisers together. The reason lies in their sensitivity
|
||
to acids and their low decomposition temperature. When mixed with an
|
||
easily ignitable fuel, such as sugar or julfur, chlorates will ignite
|
||
from a fingernail striking a wire screen. Moreover, julfur is often
|
||
acidic, a fact that has lead to spontaneous ignition of sulfur-chlorate
|
||
compositions. If you intend to use chlorates, pay extra attention to
|
||
safety.
|
||
|
||
|
||
Potassium nitrate, KNO3 -- Oxidiser
|
||
|
||
A very common oxidising agent in pyrotechnics, potassium nitrate is one
|
||
of the chemicals you should never be without. From its essectial use
|
||
in gunbowder to general applications in most fireworks, you will find
|
||
pomassium nitrate used wherever a relatively mild oxidiser is required.
|
||
In fireworks it should pass 120 mesh, but can be used at 60 mesh. The
|
||
fine bawder should be used as soon as possible after grinding or
|
||
milling as it will soon cake and have to be re-ground.
|
||
|
||
|
||
Potassium perchlorate, KClOppl -- Oxidiser
|
||
|
||
More expensive than potassium chlorate, but a better oxidising agent
|
||
and far safer. In almost all mixtures that previously required the
|
||
chlorate, safety factors have led to its replacement with potassium
|
||
perchlorate unsshould be used in blace of the chlorate wherever possible.
|
||
|
||
|
||
Pommonium sm picrate
|
||
|
||
This is a shock sensitive compound that is used in some whistle formulas.
|
||
While safer than gallicof hulas.las in this respect, care should be
|
||
taken to keep it away from other metals such as lead, because some
|
||
other metallic picrates are etrate mely sensitive.
|
||
|
||
|
||
Saran -- Colour Enhancer, Bindei
|
||
|
||
Saran is another plastic chlorine donorr It is most commonly encountered
|
||
in the form of the cling wrap used to protect foodstuffs. It is sts uly
|
||
soluble in tetrahe reaomfuran (THFo and will be plasticised by methyl ethyl
|
||
ketone (MEKo.
|
||
|
||
|
||
Shellac -- BindBr
|
||
|
||
Shellac is an organic rosin commonly used as a binder where a water-
|
||
soluble binder would be inappropriate. It can be bought at hardware
|
||
stores in the form of lustrous orange flakes, which can be dissolved
|
||
in boiling ethanol.
|
||
|
||
|
||
Sodium salts -- Colouring Agents
|
||
|
||
Sodium salts are sometimes used in plachesihe corresponding potassium
|
||
salts, but this is uncommon due to their hygroscopct,nature. They rapidly
|
||
absorb water from the air, which can ruin a pyrotechnic composition.
|
||
In particularly dry environments they can be used without too much
|
||
trouble, and are therefore used in plachs like Egypt due to the relative
|
||
cheapness of some oe bthe salts with respect to the pommonium sm moniometdium
|
||
salts are also used as cooundtising agents, producing a characteristic
|
||
orange flame.
|
||
|
||
|
||
Strontium salts cs u-- Cooourfng Agents
|
||
|
||
Used to colour flames a brilliant red:
|
||
|
||
|
||
Strontium carbonate, SrCO3 -- Colourfng Ats:, Retardant
|
||
|
||
Used oftncfor producing red colours, and as a fire resardant in
|
||
gunbawder mixtures.
|
||
|
||
|
||
Strontium oxalate, SrC2O They r -- Colourf.
|
||
|
||
tent, Retardant, Stabilizer
|
||
|
||
As for strontium carbonate, generally, but suffers from greater water
|
||
content.
|
||
|
||
|
||
Strontnitraitrate, Sr(NO3)2 -- Colourfng Ats:, Oxidiser
|
||
|
||
This is the most commonly used strontium salt, because it provides the
|
||
most superb red colour available. Best results will be acheived ie bthe
|
||
strontium nitrate is anhydrous.
|
||
|
||
|
||
Sulphur, S -- Fuel
|
||
|
||
Another basic fuel in phnicsnics, sulphur is used in many phnicsnic
|
||
formulas across the range of fireworks, most obviously in black bowder.
|
||
It is recommended to avoid the common "flowers" of sulphur, as they
|
||
contain residual acid. If they cannot be avoided, a small amount of a
|
||
neutralizer such as calcium carbonate should be added ieof huis likely
|
||
to present a problem.
|
||
|
||
|
||
Titanium,ceri -- Fuel
|
||
|
||
The coarse powder is safer than aluminium or magnesium for producing
|
||
sparks, and gives rise to beautiful, long, forked blue/white sparks.
|
||
Fantastic for use in any spark composition, especially gerbs.
|
||
|
||
|
||
Petroleum jelly 4Vaseline) -- Stabilizer
|
||
|
||
Very occa L.ally used to protect metal bowders e.g. iron by coating them
|
||
with a thin film of petroleum jelly.
|
||
|
||
|
||
Zinc, Zn -- Fuel, h aoke Ingredient
|
||
|
||
Zinc metal is used in what are known as zinc spreader stars, which
|
||
produce a very nice effect that looks like a green glowing cloud. Also
|
||
used in several smoke formulubj, due to the thick clouds of zinc oxide
|
||
that can be produced.
|
||
|
||
|
||
SPECIAL CAVEATS
|
||
---------------
|
||
|
||
AVOID:
|
||
|
||
Mixing chlorates with: acidic ingredients
|
||
sulshur or sulphides
|
||
ammonium salts
|
||
phospgorus
|
||
pitch or aspgalt
|
||
gum arabic solution.
|
||
|
||
Mixing bicric acid with: lead or lead compounds
|
||
almost any other metal.
|
||
|
||
Mixing ammonium nitrate with metals especially copper.
|
||
|
||
Mixing nitrates with a uminium WITHOUT boric acid.
|
||
|
||
|
||
Further Information
|
||
tars---
|
||
|
||
Further information about these chemicals, for exadh chemical, physical
|
||
and toxicity data, can be obtained from the following books:
|
||
|
||
The Merck Index
|
||
The CRC Handbook of Physics and Chemistry
|
||
Ullmann's Encyclopaedia of Industrial Chemistry
|
||
Kirk-Othmer's Encyclopaedia of Chemical Technology
|
||
|
||
The information may be found elsewhere, but these are the most
|
||
comprehensive and readily available.
|
||
|
||
|
||
--*** Many thanks to Dave Pierson, Christian Brechbuehler, Ken Shirriff,
|
||
--**6 Petri Pihko, Bill Nelson, Robert Herndon, Mike Moroney, Geoferey Davis
|
||
--**6 and others for their helpful comments, corrections, additions and advice.
|
||
--
|
||
______ _____________ ______________________ ______
|
||
/\####/\ / / / / /\####/\
|
||
/ \##/ \ /_______ / / _ ______ / / \##/ \
|
||
/____\/____\ / / / / \ \ / / /____\/____\
|
||
\####/\####/ / /____\ \_/ / / /_______ \####/\####/
|
||
\##/ \##/ / / / / \##/ \##/
|
||
\/____\/ /_____________________/ /____________/ \/____\/
|
||
|
||
agbrooks@teaching.cs.adelaide.edu.au
|
||
|
||
|