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Author: Subject: Spontaneous Ignition
Armistice19
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sad.gif posted on 17-11-2010 at 19:14
Spontaneous Ignition


I'm sorry to bother you smarter and more intelligent peoples of the forum, however I am obviously at a lack of preventative safety knowledge. After purchasing my first ball mill a couple weeks ago I began milling some aluminum for flash composition. Each time I milled the material for multiple days in hope of reaching "air-float" German Dark. At first I opened my mill to view my new creation only to realize that now that it had been exposed to oxygen it was now burning in the air. I tried a second time, however this time I allowed the media and material to cool down for a bout an hour and a half. It was my assumption that the spontaneous ignition was due to the heat caused by friction of constant milling for long periods of time. I opened my mill and thankfully this time my aluminum powder did not spontaneously ignite.....immediately. It wasn't until I began sifting, and separating the aluminum away from the media that bright glowing embers slowly began to appear and before I knew it I was rolling up my favorite carpet and putting it on the side of the road for the garbage men to retrieve the next morning. The newspaper that I was using to accumulate the sifted aluminum powder was now melted and infused by heat onto my carpet from the ensuing blaze. If this happens again then I am going to have to reconsider weather or not this particular hobby is really for me. In all honesty the safety of me and my family if of utmost concern, and because of this I am very close to giving up on this sort of thing all together.



“Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.” -Albert Einstein
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Sedit
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[*] posted on 17-11-2010 at 19:35


I have never performed such an experiment so this is all theory, if im wrong someone will correct me without a doubt.

How about milling it with some sort of inert solvent so that its oxygen reactivity never really becomes an issue until the solvent dries. It would hinder sifting operation though but given the fine partical size I don't feel that sifting will ever be a good idea with such finely divided Aluminum. Even if you manage to have it not go up in flames you will still end up with heavy oxide contamination.





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[*] posted on 17-11-2010 at 19:48


idk what your trying to do the best way to make flash is to buy the preground Al flake and perchlorate and mix on a sheet of paper
dont forget to make a static wrist band that ties into the wall plus use static spray
ball milling is better left to the factory just buy the Al powder its sometimes 14 bucks a LB
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Armistice19
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[*] posted on 17-11-2010 at 20:25


I could easily mill my next batch with a solvent as my current ball mill is manufactured with liquid milling in mind. It is composed mostly of neoprene, and it certainly makes an airtight seal after the seal, lid, washer, and nut are secured tightly into place. As for crazedguy, I certainly understand that aluminum powder can be purchased and is readily available online from chemical pyrotechnic suppliers, however pound for pound there really does not exist a more economically friendly way of obtaining high grade aluminum powder.



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[*] posted on 17-11-2010 at 20:41


wouldnt the particle size be reduced because of friction and if you use a solvent the friction would be reduced maybe stopping the milling
i dont really know much about milling just have a lot of experience with flash powder
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[*] posted on 17-11-2010 at 21:01


I have heard of incidents similar to this, some causing quite a bit of damage. A particular incident I recall reading a few years back was an experienced pyrotechnic hobbyist, who wanting some ultra fine magnesium, milled some coarser granules to get the desired particle size. Upon opening the ball mill the magnesium dust instantly ignited causing a massive fireball with alot of heat, miraculously the man escaped with only mild burns.

Anyway I would suggest you do this: I assume you are starting with Al foil and milling it down over the period of a few days. I would suggest that you open the ball mill and let the Al powder remain in contact with the atmosphere for an hour or two. Do this once or twice a day until you are done milling. While this may seem counterintuitive it really isnt, aluminum is actually quite a reactive metal and when exposed to O2 it forms a layer of Al2O3 which protects it from further oxidation. So heres what I suspect is going on, as you mill the Al you destroy the passivating layer while at the same time increasing the surface area by alot. So when you finally so expose the ultra-fine Al to atmospheric O2 it rapidly begins to form Al2O3, and after a certain point enough heat energy is released to ignite the Al.

So hope that helps, and be careful.
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[*] posted on 17-11-2010 at 22:33


My two cents - don't mill so fine. Unsifted your material will have a range of
grit sizes spanning from around 400 on down to dust that will suspend in air.
To obtain a visual reference of grit sizes see how those look in sand paper.
There is no benefit and some detriment to going beyond 600 # grit , since
the greater exposed surface area means more oxygen bound to the material.
Spontaneous ignition means that it has not been passivated , in other words
the powder surface is raw aluminum which heats from reacting with air. The
lapidary drum ball mill is I expect hermetically sealed when it runs. The only
available air contained within it's small volume is quickly consumed as the
grains are fragmented to expose more surface and much aluminum will remain
with no oxidized surface. When first opened pour in some drug store variety
70 % rubbing alcohol to protect and cool the material by evaporation. Spread
out the powder on a cookie pan stirring and turning at intervals to dry , as
it does it will develop the oxide layer. When it is dried and free flowing it
can then be sifted to separate the finer material from the courser grains
which can be milled some more.

.
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[*] posted on 17-11-2010 at 23:36


It does seems counter productive franklyn, Your suggesting he create a messload of the oxide to protect the Al which is what he is trying to avoid. If the heat is generated then the oxide is formed, end of story. What he needs to do is protect the HIGHLY reactive particulate without interference from atmospheric oxygen which is leading to the issue at hand.

Inert atmosphere would be great but in this case a huge pain in the ass to say the lest. Better to possibly try extreme cold to slow reactivity and with winter comming it should be simpler then it sounds

Next person that say to buy a reagent that someone wishes to synthesize I might just have to cyber slap BTW. Your wasting our time here at science madness 99.9 % of the time

Shit yall are gonna make me have to clean out my ball mill which is contaminated with Lead right now so I stayed away but this topic just bugs me because I know I could do it right yet never have.



All in all, Avoid the sifting for the moment and perform your seperation mechanically under a solvent by hand if needed else you will have the reactivity issues come into play.

Is it really needed to have a very precice partical size that its worth risking the eintire batch?





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[*] posted on 18-11-2010 at 00:44


@ Sedit
Scratch aluminum and the exposed surface becomes oxidized within minutes.
A fine powder without surface oxidation will combust in air with minimal prodding.
This is only useful as a reagent and suicidal for pyrotechnic applications.

.
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[*] posted on 18-11-2010 at 02:59


Quote:
In all honesty the safety of me and my family if of utmost concern, and because of this I am very close to giving up on this sort of thing all together.

To prevent its ignition, freshly milled Al should be exposed to air very gradually.
Opening the lid on an airtight container allows air to contact the powder much too suddenly.
After milling, air should be allowed to leak slowly into the container for some time before opening.
This will prevent the sudden oxidation that would heat the Al to ignition.



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[*] posted on 18-11-2010 at 06:39


Quote: Originally posted by franklyn  
@ Sedit
Scratch aluminum and the exposed surface becomes oxidized within minutes.
A fine powder without surface oxidation will combust in air with minimal prodding.
This is only useful as a reagent and suicidal for pyrotechnic applications.

.


This is right on the money.

But a few questions have not been answered and some information is missing. I have milled Al quite some many times with this phenomenon not occurring once.
This problem does NOT have to occur. But much more information needs to be determined.

What was used as milling media?
What was the source of the original Al?
What was the mill container constructed of?
What was the speed of the mill RPM and did was the unit closed to air?
How long did this milling continue unabated?
Was any other materiel used in the mill & was there any materiel added to the Al?


Generally speaking continual milling with no pausing for a moment to open the mill container invites certain problems. Steric Acid used as a mild lubricant is generally standard. Milling media should be altered during the process as what may have been appropriate for tearing the foil and shearing process is not the best for further reduction.

One does not allow the continual mill process to continue uninterrupted for several days on end. The media should be altered. A mild lubricant in very tiny amounts utilized.

If Al foil is used the first step is to reduce it prior to milling and make sure it is really pure and uncoated. Buy the cheapest foil available: it generally does not have a coating of any sort. Then use a scissors to cut that into small sections and place into a blender: this will chop it in to tiny (round) sections that work very well with the STARTING mill process. Use hard surface media first to created a flake shape. Add a very tiny amount of steric acid or similar. Run the mill for 24 hours and open [the container]. Run the mill for 36 hrs and open again. Run the mill for two days max and open each time. Initially heavy glass marbles or brass spheres work very well. Eventually smaller (.5 inch) lead balls are appropriate for extremely fine Al.

NEVER allow the mill to run without opening. Never use a media that may contain other materials (stone, etc). Never use a container that has not been cleaned completely! Slower speeds are actually more effective than faster.
Using foil is a slow process. Floor sweepings from milling is generally very fast materiel to mill. Differing aluminum result in differing outcome. Some is VERY brittle and will granulate rather than flake, eventually getting extremely fine and weeping and surface lubricant. Exposing Al to air allows the oxide to exist: sealing it throughout the process will not.

Mistakes can be overcome IF the process of any synthesis is examined in detail. Energetic materials (Energy experiments in general) are unforgiving. The more research beforehand limits mistakes provided you understand the process and what is happening.
Milling pure Al is dangerous and that is why oxidation is allowed to occur. Keeping the Al from mixing with other materials is also a "no-no", that why everything is cleaned.

With no exaggeration I would say I have milled well over 40lbs of Al & about 10lbs of Mg and not had this problem occur. I have gotten some of the finest Al I have ever examined (under a microscope) via standard methods. This process CAN be done very safely. You MUST examine what you are doing that is causing this to occur! It may be as simple as not opening the container at intervals. Try 12-24 hours continually. Make SURE that everything is unadulterated.
All too often the Al sold on eBay (especially) & by some pyro dealers are adulterated with carbon (often as high as 25%). This is NOT due to some "foil-paper burning process" but simple greed. The older process had perhaps 2-5% carbon that appeared attached to the flake Al. There also was a Al powder than had some Teflon. This was from sweepings from two factories and a great deal of powder made from it. It was extremely dangerous but the opening of the containers allowed oxidation to build and even though the Teflon was there, limited tragic incidents resulted. It was unusually reactive to say the least!!!

-=Work in safety=- NO ONE HERE WANTS TO SEE YOU HARMED! And what's more, you CAN achieve a very safe working condition. It is never a good idea to conduct work in the home. but if no other place is available, never leave anything unattended. If you need to leave. Turn off the mill. If it takes a few more days: so what? Keep you weight levels down until you understand any problems that may occur. Be strictly aware of any fire danger.
You MAY be doing everything correctly and sparking from some source (motor brushes) MAY be the cause of a flash of air-float Al that you simply didn't realize!!! Ask questions: people will treat you with respect. No one wants to see you harmed or your stuff fucked up...



[Edited on 18-11-2010 by quicksilver]




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[*] posted on 18-11-2010 at 08:10


Quote: Originally posted by franklyn  
@ Sedit
Scratch aluminum and the exposed surface becomes oxidized within minutes.
A fine powder without surface oxidation will combust in air with minimal prodding.
This is only useful as a reagent and suicidal for pyrotechnic applications.

.


wikipedia says : "Metallic aluminum is very reactive with atmospheric oxygen, and a thin passivation layer of alumina (4 nm thickness) forms in about 100 picoseconds on any exposed aluminium surface.[5] This layer protects the metal from further oxidation."

Actually the practice in the pyro community is to keep opening the mill jar at regular intervals. If, for example you mill for a week, make a habit of opening the jar every 12 hours at least, leaving it open for about a minute or two. this will create the oxide layer on the fresh surfaces, but won't lead to ignition temp, as you would get from the huge surface area of 1 week milling time.
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[*] posted on 18-11-2010 at 08:59


Add 3-5% of a viscous silicone oil before milling (Other oils, like motoroil makes your rubber drum swell like crazy) and after milling is done, take the drum from the rollers and leave it (STILL CLOSED!) somewhere outside for 3-4 days or so. The very small amount of oxygen that is able to get into the drum will passivate the aluminum in a controlled way. Another thing that I used to do is simply opening the lid and quickly closing it again for a couple of times. Be carefull though not to produce a dust cloud while handling the drum, as once happened to me! :o

Despite these difficulties I still think milling in an nearly airtight drum is better. If continuously the aluminum is passivated-depassivated by erosion-etc you will probably end up with pure aluminum oxide pretty quick...:)


[Edited on 18-11-2010 by nitro-genes]
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[*] posted on 18-11-2010 at 09:03


Quote: Originally posted by Armistice19  
I'm sorry to bother you smarter and more intelligent peoples of the forum, however I am obviously at a lack of preventative safety knowledge. After purchasing my first ball mill a couple weeks ago I began milling some aluminum for flash composition. Each time I milled the material for multiple days in hope of reaching "air-float" German Dark. I am very close to giving up on this sort of thing all together. [snip]



First "air float" is applied to charcoal. German Dark info at the
end.

Ye old Aluminum Powder and Pastes "The Tale of the Powdered
Pig" Reynolds Metals Company, 1957. And I suspect a zillion
web sites.

Hammered aluminium powder is lubricated w/
"stearic acid is commonly used, although tallow, olive oil, rape
seed oil or other oils may be employed."

Wet ball milling — "An inert liquid such as mineral spirits is also
added ...."

----------
Extracted from:

A Buyer's Guide for Aluminum Metal Powders
Ken L. Kosanke
PGII Bulletin 27 & 28 November, 1981 & December, 1982

Back issues available from the PGII [ www.pgi.org ]


1) The number one question concerns the definition of the very general descriptive
terms -- dark, light and bright. I think these are poor terms and their use should be
avoided. They are much too general and can mean quite different things to various
people. These differences (between kinds of aluminum powders) can be very signifi-
cant. Even subtle differences, not detectable by eye or feel, can produce significantly
different pyrotechnic effects (more on this later).

Dark USUALLY refers to very fine flake aluminum, with finer flake USUALLY appearing
darker. This is a consequence of light reflecting off the more numerous irregular particle
surfaces. However, an exception is "German dark" aluminum. Here most of the dark
color is from the presence of carbon, resulting from its manufacturing process more on
this later). There are at least three grades of German dark, all appearing quite dark, but
all having different particle sizes. Obviously in this case, darkness of appearance is no
guide t particle size. It has also been reported in the literature that some manufacturers
add carbon black to their products. Again, darkness is no guide to particle size.

To MOST pyrotechnists, bright, not light, is the opposite of the attribute dark.
USUALLY, bright refers to flake aluminum's, but the flakes are large enough (if free of
carbon) to appear shiny (bright). Bright flake aluminum can still be very fine and very
reactive.

Light USUALLY refers to atomized or finely ground aluminum's. The particles of
aluminum have more of a 3-dimensional character than flakes. Unfortunately, light
atomized aluminum can be as dark appearing as dark flake aluminum.

Confusion can be avoided by substituting more descriptive terms, such as "flake" and
"atomized", along with an indication of particle size, for the ambiguous dark, light and
bright. Possibly the one exception I make is the use of the term flitters, which are very
large flakes usually in the range of 8 to 14 mesh.

The third manufacturing process leads to flake aluminum. Here aluminum particles or
foils are either rolled or hammered into very thin flakes. In either event, a lubricant must
be added to the aluminum to prevent the flakes from sticking together and onto the
rollers or hammers. Stearic acid (stearin), a fatty organic acid, is a common used
lubricant. The presence of the lubricant often gives flake aluminum a slippery feel, and
is the reason it resists mixing with Water in star compositions. It also causes the powder
to appear shiny, and protects it from oxidation. One significant variation in making flake
aluminum accounts for essentially all of the dark color in dark German aluminum. Here
little or no lubricant is used. Instead the aluminum is rolled on or between very thin
sheets of low ash paper. After the rolling process, the material is heated in an inert
atmosphere, turning the paper to carbon.
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[*] posted on 18-11-2010 at 09:07


It is better NOT to use stearic acid in combination with flake aluminum! With stearic acid, the end product is impossible to handle without particles of aluminum floating all over the room, leaving silvery dust on everything! :)

The point of the paper process is not to turn it into carbon later btw, but creates a aluminum carbide coating that protects it from further oxidation.

[Edited on 18-11-2010 by nitro-genes]
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[*] posted on 18-11-2010 at 11:23


Quote: Originally posted by mnick12  
I have heard of incidents similar to this, some causing quite a bit of damage. A particular incident I recall reading a few years back was an experienced pyrotechnic hobbyist, who wanting some ultra fine magnesium, milled some coarser granules to get the desired particle size. Upon opening the ball mill the magnesium dust instantly ignited causing a massive fireball with alot of heat, miraculously the man escaped with only mild burns.


Ball-mill-1.jpg - 889kB Ball-mill-2.jpg - 847kB Ball-mill-3.jpg - 813kB

This is your basic thermite® type reaction. A standard lab demo
is to burn Mg ribbon in quartz sand. See also —

William D Jones
The Magnesium + Cab-O-Sil Fiasco
Reprinted in : The Best of American Fireworks News V
(The Best of AFN series can be had from http://www.fireworksnews.com/



---------
donald j haarmann
rec.pyrotechnics
December 8, 2005

"Lloyd E. Sponenburgh" <LLoy...@mindspring.com
|

| I suspect is was a combination of a localized ignition of a small amount of
| Mg between the balls, along with atomized Mg from the agitation of the
| balls, and (*possibly*) a silane reaction with the SiO2 (Cabosil) in the
| jar.
|
| I've run Mg in a jar only once -- ONLY once, and I was not milling it. I
| got severely injured. I, too, had Cabosil mixed with the magnesium.
|
| LLoyd

Silane! Buff and Wöhler's Siliciuiumwasserstoffgas (siliciuretted hydrogen)! I have my
doubts. The only source of hydrogen being moisture and just how the water would be
decomposed remains a question. Burning magnesium and cabosil perhaps could in the
presence of moisture release a combination of any of the 6 silicon hydrides, however,
absenting a lot of water the amounts would not be significant. It is, however, well known that
the mechanical treatment of chemicals can increase their reactivity.

Dropping ball upon balls ... the point contact area cannot be great (I have at this time been unable
to find a equation or table of sphere point contact areas vs. diameter) therefore, a lot of energy
can be generated over a small area by the impact of two balls.

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Armistice19
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[*] posted on 18-11-2010 at 16:21


I use value time aluminum foil to start with, its about 75 cents a roll and its perfect for my applications. I take the foil and fold it over itself several times before I tear it into smaller pieces. I then use a blender to obtain finer granules. The granules are then put in the mill and let go non stop for 7 days. (I realize now that milling for this long continuously is a life threatening mistake.) My ball mill is composed of 2 air-tight neoprene containers, and my media is non sparking Lead-Antimony balls. The RPM's on my ball mill is 60 AT MOST. From now on I will need to be exposing my aluminum powder to oxygen on a regular basis while milling. I have plenty of 100% pure silicone oil around the house which I could use as an added safety measure.



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[*] posted on 19-11-2010 at 14:59


I had a similar experience with silver thermite going up on me and causing third degree burns over a good portion of my body... not fun. It really brought back the memories to read that post WiZard.



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Armistice19
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[*] posted on 19-11-2010 at 18:39


So I opened my second container today after leaving it open a crack overnight. It did not spontaneously ignite. However my lead-antimony media was toast. It was lumpy and had distorted shape. At first I thought it was simply coated with lumps of aluminum powder but I soon realized the problem was much more permanent. The lumps were very solid and had become infused with my media. I suppose this might have also been caused by too much continuous unstopped milling. Since I am working with my oxidizers and fuels separately, I think that Alumina cylinders will be my next choice of media. Also what benefits come from adding lubricant to my aluminum during milling?



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[*] posted on 19-11-2010 at 19:37


The problem with Lloyd's accident report in AFN as posted by The Wiz is that the "dilutent" that Llyod was mixing with the magnesium was an *OXIDIZER*. Magnesium will steal the oxygen off of many materials that one might normally think to be inert. In this case, cab-o-sil is chemically SiO2...note the two oxygen molecules ready for action.

Commercial aluminum, even the "dark" aluminums, are lightly stearin coated to prevent spontaneous ignition during mfg.
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[*] posted on 20-11-2010 at 11:48
oxidizer? we don't need no stick'n oxidizer


Quote: Originally posted by FrankRizzo  
The problem with Lloyd's accident report in AFN as posted by The Wiz is that the "dilutent" that Llyod was mixing with the magnesium was an *OXIDIZER*. Magnesium will steal the oxygen off of many materials that one might normally think to be inert. In this case, cab-o-sil is chemically SiO2...note the two oxygen molecules ready for action.

Commercial aluminum, even the "dark" aluminums, are lightly stearin coated to prevent spontaneous ignition during mfg.



Tell the WiZ (Donald J Haarmann)
American Fireworks News
Number 19 March, 1983

Dear WiZ: I have, after a 25-year hiatus returned to fireworks, my renewed interest
in which coincided with the arrival of last year's tax refund. I promptly ran amok,
ordering a pound of this and that and soon had a fine collection of pyro chemicals. I
felt confident that I could, on a moment's notice, whip up any formula published.
Wrong. As luck would have it, when Jerry Pulice's Whistling Titanium Rocket article
was published (AFN #9) 1 found I lacked 10-28 mesh titanium and had only 100
mesh or some very coarse sponge which I had obtained from Jim Finckbones’ Mega
Tech (of whom it can be said, here is a pyro who has paid his dues).

The problem of reducing the 4 mesh sponge to 10-28 mesh seemed a simple
problem of running it through my kitchen blender. So I proceeded to dump the entire
pound in the blender and start it on Speed 1 (my blender has seven speeds).
Click-it-ter, click-it-ter, click, snap, crack, ting-ting; it would seem that a little higher
speed was in order. So, on to No. 2, then 3, now 4 and then 5 and WHAT-HO, along
with the click-it-ters, snaps, tik-tik, bang-bang, clinks and rattles, there were little
white sparks going around in circles, along with the titanium, when HOLY
PYROPHORIC BATMAN – the-the-the inside of the blender just lit up like a light
bulb! Now the top has blown off and titanium dioxide smoke and finely divided Ti is
issuing forth. It rapidly became a race to turn off the blender and at the same time
keep my laundry bill to a minimum.

Hummmmm, no doubt a fluke so this time I tried it again, but using a three-foot
dowel rod to push the buttons. All was OK.(even fine) until once again Speed 5 was
reached and once again FLASH-POP SMOKE. All of which leads me to write to my
WiZ with my plaintive question: WHY ME?

signed G. R. Phlegmone

Dear Phle: The answer to your question is less obvious than would appear. It would be
simple to put it down to "just another nut job", however we pyros as a group are given
to mixing together finely divided, highly reactive metals, along with strong and not
particularly stable oxidizing agents. Then, not being satisfied, we add fuels like gums
and charcoal. And for the height of folly, we put a match to it!

There is, of course, a rationale to all this: fireworks are fun.

Now as to what happened and what to do about it, the following may be of some
use/interest. As you have astutely observed ' titanium, along with several other metals,
is pyrophoric, that is, they are 1) capable of producing a spark when struck (as with a
blender blade), 2) burning in air spontaneously (indeed, some months ago a well known
pyro was burned when some Ti powder ignited as he was pouring from one container to
another). What probably saved you was the limited amount of oxygen available in the
blender and when the heat from burning raised the air pressure add blew the top off,
the powder was dispersed sufficiently so that the reaction was not sustained.

Now things to do. You could Simply buy coarse Ti but then I would be out of a job and I
need the money. Being a Wizard ain‘t cheap. Now, as the Ti is rather reactive with air,
we have the choice of either removing the air by placing the blender in a vacuum
chamber (shouldn't cost more than a couple of grand) or of placing the blender in a
cabinet and displacing the air with an inert gas such as krypton. This is simpler than the
vacuum chamber but lacks elegance.

What is needed is an inert gas that could be poured into the blender to displace the air;
as luck would have it, there is such a gas, sulfur hexafluoride. Not only is it inert and
non-toxic, but it is five times heavy as air.

There is the eternal problem: where to buy it? The Sears catalog doesn't list it and a
quick check of the J.C.Whitney catalog failed to reveal it. So. we have to call out the
heavy artillery, that is, to barter. If you live in a "closed" state and have access to Class
C, you have a great item to barter.

Now SF is commonly used as an insulator in high voltage work, so grab a handful of "C"
and truck over to your local power plant with a big plastic bag and trade for some. If you
choose to buy it, at $10.30 a pound in 10 pound lots liquefied in a steel cylinder, you
should have about a 7,000 year supply. If you don’t like the plastic bag idea and you
are a physics fan, the fact that the critical pressure of the gas is only 2,206 kPa & 21
deg. C. will be of some use:

When you get it home, pouring it into the blender will be a bit of a chore as it is
colorless . You will have to fall back on by-guess and by-gosh or if you have one
handy, a Schileren set-up will be useful. If you decide to use this method, please drop
me a note so that I can check the horizon for smoke now and then.

[Who would put titanium in a blender? I’ll never tell!] /djh/


djh
----
Hudson Maxim
Dynamite Stories 1916

DEDICATION
INTRODUCTION
To the actors in the comedies and tragedies of real life without whose efforts and
sacrifices the stories could not have been so interesting and true, this volume is with
grateful acknowledgments most respectfully dedicated. As the parts played by the actors
were not rehearsed, the performances have required a little retouching in the interest of
the reader, the author having subordinated history to story rather than story to history.


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franklyn
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[*] posted on 22-11-2010 at 22:51


Quote: Originally posted by The WiZard is In  
The Magnesium + Cab-O-Sil Fiasco
Reprinted in : The Best of American Fireworks News V
The Best of AFN series can be had from http://www.fireworksnews.com

http://www.sciencemadness.org/talk/viewthread.php?tid=14884#...

This has all the earmarks of a Texas tall story. While the intrepid victim
may well have been singed , credibility is lost with embellishment.


" My mill jar was a one gallon capacity PVC jar "

" The mill jar was still on the mill with the quite, green white glow of
burning magnesium emerging from it's mouth. I put out the jar fire
with dry sand "

" The jar - was burned to ruin by the fires inside "

" A welder's helmet was hanging in the line of fire - it was charred
almost to destruction.

" I poured cold water over the burns for a couple of minutes until
fires caught my eye. There were several small fires burning in and
around my milling shack."

- Although PVC is intrinsically fire retardant because of it's
relatively high flash point ~ 435 ºC and 57% of it's weight is Chlorine,
the heat of a magnesium flare would liquefy and ignite the container
with napalm like combustion. Even with the shack open , 2 minutes
is the mean time for flashover and conflagration of everything. The
events as described don't correlate intense heating with little fire.

http://www.chemexper.net/specification_d/chemicals/supplier/...
( It should be noted that PVC , magnesium , and a nitrate salt constitutes
tracer composition for rifle ammunition )
http://tinyurl.com/366allw
http://tinyurl.com/393fprh


" my arm had third degree and second degree burns. The left side of
my face was a mass of very shallow third degree burns. The delicate
new skin below was sore and pinked , but otherwise healthy."
- Although the writer goes to extensive detail of his injuries no where
is there any mention of the scabbing which must necessarily occur to
be consistent with what is claimed.
- Third degree burn means total loss of skin requiring grafts to replace it
and hospitalized in an intensive care burn center.



" I went through Special Forces training in the Navy "
- Huh ? Special Forces is an army outfit. Generically " Special Forces "
refers to Navy Seals also but it is seldom referred to as such , and while
many military branch facilities provide interservice training , basic survival
skills are service specific.


" They also taught us how to recognize shock in one's self , and
how to treat it."
" the next day I saw a doctor - " Damn Lloyd ! You could have died !
I've seen people die from shock with less than this ! "
- Shock is the medical term for excessive blood loss. Had the ' doctor '
received Special Forces training also he would have known that.


.
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bbartlog
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[*] posted on 23-11-2010 at 04:15


Seems like nitpicking. Sure, he may not in fact have had third degree burns to the extent claimed. His 'couple of minutes' might have been only 15 seconds - who knows how someone's perceptions of time would be affected in that situation?

As for the rest, it seems like
- the SEALs might not have existed under that name at the time that he would have trained
- almost the entire reaction would have occurred outside the PVC jar (that being where the oxygen was), limiting its involvement
- 'shock' does not necessarily imply blood loss; you sure can get shock from being badly burned; and even if there is some narrow medical definition that meets your criteria there's no reason a doctor couldn't have been speaking colloquially.

In short it seems like you're grasping at straws to throw doubt on a perfectly plausible story.

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watson.fawkes
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[*] posted on 23-11-2010 at 05:43


Quote: Originally posted by franklyn  

This has all the earmarks of a Texas tall story. While the intrepid victim may well have been singed , credibility is lost with embellishment.

" My mill jar was a one gallon capacity PVC jar "
The fellow who relates the story is the author of the book Ball Milling Theory and Practice for the Amateur Pyrotechnician. In it he describes the construction of mill jars from PVC plumbing pipe and standard fittings. His one gallon jar has a main body of 6" diameter pipe, 8" long.
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[*] posted on 23-11-2010 at 12:06


FWIW Franklin has some valid observations.2nd/3rd degree burn victims of the degree described aren't sent home with antibiotic cremes etc to care for themselves.Home care and recovery:o
I wont bore you with military terminology/history but rest assured a Navy SEAL would never refer to himself as SF and vice versa.
I cant comment on the rest of his story but the military and injury parts of the story sound like artistic license to me.:D

[Edited on 23-11-2010 by grndpndr]

[Edited on 23-11-2010 by grndpndr]
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