Pard
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Filler material (and it's specific density) for dynamite mixtures
Hello, I'm wondering what the density of the sawdust used in NG dynamite was? I imagine it'd be like the woodmeal or woodflour type instead opposed to
the kind with chips and larger pieces, like what might be used in a smoker.
Could somebody please explain it what the reason for this is? I thought the point was it just needed to be absorbant. Or is the finer material more
available when it goes.
Also, anything to add about using diatomaceous earth, ammonium nitrate, charcoal and other filler materials. Some personal experience would be very
helpful
Attached (if the picture comes to show up) is something from a file I remembered seeing and thought I'd add here. Why do some mixtures recommend kno3?
edit: Also if somebody could tell the standard stick of dynamites amount of NG, that would be good to me.
[Edited on 29-12-2013 by Pard]
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Ral123
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Here's the classic cheap ass home made dynamite(UN/EGDN):
http://www.youtube.com/watch?v=37q_QyKDrGA
How can 70%KNO3, 20%NG and 10% sawdust be called dynamite. Doesn't that require a booster, strong confinement and low density to go off?
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Hennig Brand
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It is initiated very easily actually. Half a gram of mercury fulminate or TATP pressed well in a paper casing worked for me in the past for similar
mixtures. I normally use corn starch though instead of sawdust. A few wraps of waxed paper or the sides of a polypropylene pill bottle was all there
was for confinement. It is easy to significantly reduce the sensitivity of such dynamites by excessive pressing when loading though yes.
Both NG and the nitrate salts used are oxygen positive, meaning they have more than enough oxygen to convert all carbon to CO2 and all Hydrogen to
H2O. The fuel is added to make use of the extra oxygen and also as an absorbent for the liquid nitric ester. Diatomaceous earth is able to absorb very
large quantities of NG. Finer particles react more quickly, and completely usually, which is desirable in an explosion. The smallest particles come
from molecular explosives. Particle size of fuel, and oxidizer, can be manipulated to control detonation velocity to some degree.
[Edited on 29-12-2013 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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DubaiAmateurRocketry
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Quote: Originally posted by Ral123  |
How can 70%KNO3, 20%NG and 10% sawdust be called dynamite. Doesn't that require a booster, strong confinement and low density to go off?
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That mixture is mostly likely to b epositively oxygen balanced since both NG and KNO3 are OB positive. I also think 20% NG is too hard to detonate ?
KNO3 barley even does something.
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Hennig Brand
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The use of KNO3 and other nitrates in dynamites was used for many years especially before ammonium nitrate came into widespread use in the explosives
industry.
According to Wikipedia "Dynamite is usually sold in the form of cylinders about 8 in (20 cm) long and about 1.25 in (3.2 cm) in diameter, with a
weight of about 0.5 lb troy (0.186 kg)." From talking to people who work in the mining industry, etc., dynamite came in a variety of different sizes,
some of which were very large (many pounds).
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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Ral123
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What I like about KNO3 is that it's much more water resistant then AN. It's interesting that BP/NG is supposed to be too hazardous but sawdust/KNO3/NG
is a dynamite?
Let's say you add 30% KNO3/sawdust to 8%NC/92%NG. You get like 20% more energetic product for the same price, the brisance is 2-3 times lower. I can't
explain to myself why diluting nice mixtures is so popular. There are even enthusiastic recipes of NM/sawdust and MEPK sawdust. What is this, dynamite
for egg cracking?
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Hennig Brand
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I have learned while blasting that when well confined in a borehole the brisance of an explosive is of much less importance (most of the time) than
for a military explosive set against a target relying on kinetic self confinement from its own mass (mass of the produced gases). With strong
confinement even relatively slow explosives often build up to max pressure in a borehole.
I like KNO3 too, but it is usually more expensive and is not a very good gas producer and does not makes as powerful dynamites as ammonium nitrate.
Ammonium nitrate produces all gaseous products on decomposition.
[Edited on 29-12-2013 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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Ral123
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What you say makes great sense. How about emulsified heavily aliminized AN/nitroester mixture, with all the empty space in the hole filled with
water/mud. The only drawback of the Al I can think of is it's price and may be reactivity.
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Hennig Brand
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From reading, I think aluminum would be used a lot more except for the price. When a commercial cost/benefit analysis is done on explosive components,
materials other than aluminum usually win out. Of course the military is usually much less concerned with cost and want maximum performance.
Never experimented with emulsions, but I do know what they are. Found the following website pretty informative. Included the little blurb on emulsions
from the site.
https://www.minewiki.org/index.php/Comparison_of_explosives
"Emulsions
Emulsions share most of the same properties as slurries. The main difference is the mixture of the explosive components. Emulsions are prepared in the
form of water-in-oil emulsions. The internal phase is composed of a solution of oxidizer salts suspended as microscopically fine droplets, which are
surrounded by a continuous fuel phase. The emulsion thus formed is stabilized against liquid separation by an emulsifying agent.
As the components of an emulsion explosive are microscopic in size and the oxidizer and fuels are so intimately mixed, emulsions have a very high VOD
and the resulting chemical reaction or detonation releases essentially all of the stored energy."
They sound really good. I don't know if they would be as useful to the hobbyist though. I don't know for sure, but it sounds like they may be harder
to reproduce properly than dynamites.
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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Pard
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edit: so Al poder works in place of sawdust, I assume tje cp,commercially available gelignite used wood though. commercial dynamo =/= military "no
spending limit stuff" The stuff you could buy back when ws designed for profit not birsance
Thanks for the input guys, you're stars
Sorry Ral123. I'm not so interested in the end result as the how and why.
"Why" a nitrate, "How" come sawdust
Big ups to henig brand for giving me the dimensions. I'm basically trying to work out tge max saturation of the NG for it's dimensions and then from
there how much it held.
The AN vs PN makes sense to me, especially considering the hydroscopic nature of AN. But that leaves unanswered why a nitrate at all. I've learned
that AN on it's own doesn't burn well but with a fuel, like sawdust, it's a different matter
http://www.youtube.com/watch?v=27qh44Ljmsg
Video very related.
I understood Dynamites had their own blasting caps. I'm not interested in making in, so suggestions for them aren't neccdesary. I understand organic
peroxides to be dangerously unstable. Given their unstability with a bit more power like NG, well personally you couldn't pay me to store them.
Lastly, my main question, the fineness /mesh of the absorbent. Is it just very fine woodmeal /woodflour (a better surface area available when it
combusts) or did they use wood chip style sawdust
excuse my spelliing, been dabbling with another of my chemica interests and can't keep my eyes open let alone type
edit: as a wee boy on my papas knee, my great uncle, his uncle had lots of sticks of what papa called gelignite. I no longer recall was he used them
for. He was having trouble storing them and beinfg the yugoslavian genius he was he figued "when they explode, they are hot, so there and fore I shal
put them in the freezer" - eventually aunt dicovered them and said "get these out of freezer!" so you know what he does? He throws them all into the
duck pond. Years later I'm trying to figure out possibly how much he had and how at risk he was. I would love a figure for my papa and to say "uncle
could've blown his 200kg freezer 2000km in 1 second using his gelignite.
Also while I'm at it, I want to know for what serves the purpose of the ntirate
[Edited on 30-12-2013 by Pard]
[Edited on 30-12-2013 by Pard]
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