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The WiZard is In
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I apply the same philosophy (actual I have raised it to
an epistemology) to these reports that I apply to movie/books
reviews. If they get a good review ... they maybe good...
if they get a bad review... they probable are stinkers.
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The WiZard is In
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Quote: Originally posted by quicksilver  | Thank you for posting that picture: most people do not own up to a mistake / injury. -- In fact you simply don't hear from them (posting) again.
It would also be extremely inappropriate for anyone to add insult to injury in this case because I can promise you that MOST of the injuries don't get
posted back on Forums such as this and they occur in alarming frequency.. |
Granted a rather liberal use of the noun Firework.
  
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quicksilver
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Many people avoid looking at the injuries, however they are a damn potent reminder of just what the consequences are.
I remember SEEING "Hand Injuries" & I just can't place it. It may even have been posted on someone's page. I don't think that was AFN.....(?) Was
it?
Now there are about half a dozen of us who are in the 40's & 50's, (& even 60's!) and have been around the block on this issue & there is
actually one MORE thing that could be said without any type of finger pointing, etc......Back when many of us used to discuss this issue on
REC.PYROTECHNICS & ALT.ENGINEERING. EXPLOSIVES (UseNet) folks used to discuss this more openly because of the increased sense of anonymity. And I
certainly understand that.
DO NOT EVER attempt to work in chemistry or pyrotechnics if you are least bit "off".
Lack of sleep, fatigue, liquor, being high, or even not paying deep and square attention to what you're doing (radio or TV, phone, etc). - THAT is
perhaps one of the most potent disasters waiting to happen.
Because all the issues [that you may be aware of] may be by-passed by the lack of strict attention!
And for goodness sake - PLEASE keep an open mind to those who may post safety issues. They are NOT doing so for any reason but to help minimize
tragedy. There is always room for an open mind. Plenty of materials are seemingly direct.....like black powder can be a source of vicious injury. But
tragedies strike even with those IF the fellow doesn't keep a clear head and strict attention. If you feel the LEAST bit "off" that day - let it go!
- "Know thy self."
I personally have a long list of things that I would do if I still were very active in this subject aside from study and reading. One of which is
keeping the amounts DOWN! If you have curiosity about a material, synthesis of a milligram level can accomplish the same thing as a weighty amount and
it will tend to minimize any tragedy.
Common sense? Of course. Even toxins such as heavy metal salts can do less harm in accordance to amount. I'm speaking here to chemistry as a whole not
just energetic formats.
I only wish that those old posts were still around because there was a great deal to be learned from them. but that should never minimize materials
that are new (or new to you).
I told myself i would not continue to add to this as it may appear to be lecturing & I'm no one who has been so perfect as to do so. Even
Spooneburger (of ballmill-book fame, etc) made a serious error......I honestly don't mean to do that; however it's such an important subject that I
almost feel compelled to stand in the "Amen" column. As years add up I can promise anyone that these discussions will bear their own witness to a
vital issue with chemistry. Please, people, keep an open mind.
I am NOT directing my comments at any individual: I give you my word on that. I deeply want to prevent anyone from the physical and mental anguish of
a mistake and tragedy because in hindsight (unfortunately) nearly every one could have been prevented.
[Edited on 17-1-2011 by quicksilver]
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Blasty
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| Quote: Originally posted by Blasty |
I find the reports on the dangers of chlorate-sugar mixtures to be a bit exaggerated. I have tinkered with them myself for several years, and not even
with the finest confectioners' sugar can they burn faster than a good black powder (at least not in relatively small quantities), let alone detonate
when unconfined without using a strong blow or a blasting cap. Not even Berge's blasting powder, which is the fastest chlorate-sugar mixture I have
ever seen (thanks to the presence of a chromate), truly detonates unless it's either given a sharp blow or a blasting cap or flash powder charge is
used to set it off. I have kept small samples of granulated Berge's blasting powder in closed plastic containers for more than a year, and there was
no sign of appreciable deterioration or increase in sensitivity.
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To give an idea of what I am talking about, for those who haven't actually tried any of these things themselves. Plain chlorate-sugar mixtures react
pretty much like this when ignited:
http://www.youtube.com/watch?v=Szpb65u3BPI
They can't burn faster than a good, well-mixed black powder. Unless given a strong blow, there just is no way that they will explode unconfined (let
alone by something as puny as "the warmth of the hands", as that report claims!)
Chlorate-sugar mixtures that use chemicals that accelerate the reaction, like a chromate, burn way faster even when unconfined:
http://www.shrani.si/?3L/RO/1vKCzI7K/berges-blasting-powder-...
But they will not explode unconfined just by igniting them (on purpose or accidentally.) In very large quantities they could, since even black powder
can do so if a large enough quantity of it is ignited, but not in the normal quantities handled by a person.
If ignited by a fuse while confined, these mixtures explode in a black powder-like manner (i.e. a violent bursting of the container), not like a high
explosive. In order to get a detonation, you need to set them off with a strong blow.
About 15 grams of Berge's blasting powder set off by a mercury fulminate cap:
http://www.shrani.si/?12/8Q/2aTECRia/berges-blasting-powder-...
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franklyn
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Charts for determining safe separation distance and exclusion area for quantities of explosive
applying the fornmula top of page 75 ( D = K ³√W ) Distance = Factor(K) times cube root of weight of explosive.
http://www.sciencemadness.org/talk/files.php?pid=205394&...
login to access references
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PHILOU Zrealone
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 Beware to what is written down here...
There is Chlorate of sodium and what is another story chlorate of potassium!
In the past I have made a lot with NaOClO2 it was widely found as 60% concentration mixed with 40% NaCl...with that concentration it was relatively
comparable to black powder...because the NaCl was tempering the burning reaction rate...
Also it depends what type of sugar you use cristaline or utrafine grinded...and the intimity of the mix (coarse or grinded ingredients)!
I did large batches of coarse 5kg sugar with 5kg NaOClO2 60% and it burns in less than a minute with a height of about 3 meters flamme and about 70 cm
diameter...
When I did use 99% NaOClO2 or 100% KOClO2 it was really another story. It is much more dangerous and faster.
I did a lot of experiments with Sulfur, carbon black of fume and CaCO3...
-with the NaOClO2 60% and coarse you get slow burning rate (except if confined). It is a bit like blackpowder but more energetic.
-with the same ingredients reduced to a fine dust you get much faster burning rate.
-with corase 99% NaOClO2 or 100% KOClO2; burning rate was about as fast as dusty mix hereabove.
Confinement always resulted in deflagration
But with fine ingredients and fine 99% NaOClO2 or 100% KOClO2 burning rate was so fast that no confinement was needed to cause a detonation...
A 3 cm high hard copper pipe 3 cm diameter and 2 mm thickness was fully disintegrated while the tube had 2 openings and was simply placed on the
ground and filled with one coffee spoon of the mix...thus about 10g
I was surprised by the speed of the straw fuse I was using with that mix...usually with 60% NaOClO2 fine powder it was like 15-20 seconds for a
plastic straw of 30 cm (and 2.5 mm diameter) filled with the mix...with that dangerous mix fuse burned in less than 1/2 second...I think it was even
faster because the plastic of the straw had not realised yet it had to melt owing to the flame that had burned into it...
Thus beware when someone claims generalities that there is no risk with chlorate and suggar mixes...it is absolutely untrue.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Blasty
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Tenney L. Davis on the relative safety of chlorate-sugar mixtures (from Sugars in Fireworks and Explosives):
| Quote: | | The chlorine dioxide which sulfuric acid liberates from potassium chlorate attacks many combustible substances and sets them on fire. The mixing of
powdered chlorate with red phosphorus is an extremely dangerous operation and can be accomplished without an explosion only when the materials are
thoroughly wet with water. Mixtures of sulfur and chlorate explode from percussion or when ground in a mortar. Sugar has the advantage that its
mixture with chlorate can be made up and handled fairly safely, and the mixture burns without offensive fumes. The ignition of such a mixture by a
drop of concentrated sulfuric acid is an interesting lecture experiment. A quantity of sugar-chlorate mixture wrapped up, with a glass bulb containing
concentrated sulfuric acid in the middle of it, makes an incendiary device which will take fire when crushed by the heel or by the wheel of a vehicle.
Time bombs employing this principle, the bulb being broken by the hammer of an alarm clock’s bell, were reportedly used by enemy agents during World
War I. |
Notice that not even the crushing action of a wheel from a moving vehicle is reliable enough to ignite them, thus why the sulfuric acid vial was
included in such incendiary devices.
[Edited on 14-4-2011 by Blasty]
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quicksilver
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Field testing of materials or disposal has had certain techniques that bear importance to this overall discussion. Whenever any energetic material is
disposed, a (somewhat narrow) hole should be dug within the earth of several feet. This allows the focusing of the blast upwards and not "outward" as
a widening cone-shape. Many people have been injured by energetic material placed on ground level and debris (rock, pebbles, etc) are forced outward
in a flatter "cone" within a blast radius. By digging a hole & planting the material to be disposed of within, the force is channeled upward and
dissipated to an extent as those objects that could be propelled are marginalized into the sides of the hole in the earth.
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pjig
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From a blasting or demolition perspective, one may also consider covering the narrow hole that Quicksilver discribed, with a large pile of dirt to
contain any debris that may result from the explosion. Blast mats are too expensive and heavy for small projects, earth is much better in confining
debris and sound ( as long as enough is put over the hole).
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Jimbo Jones
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http://www.youtube.com/watch?v=1wAtCmC6F2M&feature=chann...
Energetic materials testing ground......
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pjig
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LOL.... Thats just wrong....
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franklyn
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The Effects of Blast Phenomena on Man
http://www.dtic.mil/dtic/tr/fulltext/u2/074028.pdf
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franklyn
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U P D A T E D _ Link trom this post
http://www.sciencemadness.org/talk/viewthread.php?tid=15150&...
Effects of blast pressure on structures and the human body
www.cdc.gov/niosh/docket/archive/pdfs/NIOSH-125/125-ExplosionsandRefugeChambers.pdf
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quicksilver
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The old MKII "Pineapple" iron hand-grenade (mfg in the USA) was replaced with the 30-series of internal coil for several reasons. One of which was the
retention of energy on the container particles. In the iron grenade, the particles were larger & maintained energy for approximately 250yd, the
coil spring (30-series) grenade broke down to very small particles with poor retention of energy (bit's of spring, thin aluminum body, etc). This
provided a safety feature (somewhat...) in the the tiny light bits would not maintain driving energy, etc. Their distance for lethality diminishes.
[Authors; Person and] several others authors had mentioned the vital important of safety shielding, light weight, and extremely light
containerization. Once a weight level is reached in a high explosive the blast alone becomes a serious danger, yet if the material is kept low in
weight and the container has minimal energy retention characteristics, the level of danger is somewhat less than ignoring those factors.
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detonator
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A blasting safety distance calculation methods.
From China.
[Edited on 1-9-2012 by detonator]
Attachment: Blasting safety distance calculation..doc (87kB)
This file has been downloaded 2509 times
[Edited on 1-9-2012 by detonator]
[Edited on 1-9-2012 by detonator]
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franklyn
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http://www.sciencemadness.org/talk/viewthread.php?tid=16612
http://www.sciencemadness.org/talk/viewthread.php?tid=22554
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Joelinho
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Sadovsky Formulas
| Quote: Originally posted by Engager | There is common set of equations witch can be used for calculation of blast wave from explosive charges, it's called Sadovsky formulas. It works
regardless on nature of explosion and depends only on TNT equivalent of explosive charge. All this calculations are based on energy similarity law for
explosions witch stated that all blast wave parameters are function of two variables: first is explosion energy and second is distance from explosion
origin.
Hi,
I was wondering regarding the Sadovsky Formulas. They define blast overpressure as a function of distance from blast origin. I was wondering if they
would also be applicable in the following situation.
I use KNO3 and Sucrose in an enclosed container(pipe). The KNO3 decomposes with heat and produces O2. This O2 is then used in the combustion of the
sucrose. The rapid spike in gases causes the rupture of the container. The rupture pressure for the pipe I use is about 1800 psi.
Are the formulas applicable to this kind of blast wave or are they only for High Explosives? |
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Oscilllator
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The show mythbusters regularly blow up bricks of C-4 (and other explosives) and measure the resultant blast waves using devices that blow out at a
certain pressure. If you could be bothered, it would be very easy to obtain lots of data on the distance required before death and/or injury.
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Fantasma4500
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there was this russian guy on youtube called Fesss88 or something alike.. anyhow he used to make this sugar dynamon (95 - 5 AN Sugar)
one day he had a fuse malfunction..
500g went off when he got just as much as 2-3 metres from the charge
full detonation for sure, in a metal can
he didnt really say much about it tho.. russian mentality i guess.. havent found him on youtube since as his account was deleted
there have been back in time when they found out about yellow powder (KNO3 K2CO3 and Sulfur) some big .. well discovery.. unknown amount tho and
unknown distance, relatively weak anyways
also if others havent been mentioning this yet ''life after detonation'' is a sticky thread i believe in energetics
might give aswell some idea off a powerful bang within 'reach' literally
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testimento
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Is there any general algorithm or rule of thumb to calculate the required amount of explosive to produce similar pressure on determined distance? Like
3 bars at 2 meters, how much would stuff be needed at 4 meters or 8 meters?
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Fantasma4500
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mythbusters had some fancy tubes with a specific thickness aluminium foil covering the ends, this was supposedly showing the lethal radius
they did some stuff with being underwater if anybody cares to search for it
it was something about if you jump underwater while an above water explosion happens, would you be able to survive then?
i have felt 26.5g flash from a commercial firecracker go as close to ringing ears without actually getting ringing ears in urban enviroment, tall
buildings all around, about 20m away
40g flash approx 12m away open ground nearly ringing ears
and 11.5g flash about 10m away a hard blow to right ear as i miscalculated fuse burn time, no ringing ears
im sure there must be a limit of bar to collapse lungs etc
and that limit could be found by getting hold of the same devices the mythbusters used -- tubes with specific thickness aluminium foil at the ends
the foil gets blown inwards if pressure reaches specific mass (if you can call it that?)
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Ral123
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| Quote: Originally posted by quicksilver | The old MKII "Pineapple" iron hand-grenade (mfg in the USA) was replaced with the 30-series of internal coil for several reasons. One of which was the
retention of energy on the container particles. In the iron grenade, the particles were larger & maintained energy for approximately 250yd, the
coil spring (30-series) grenade broke down to very small particles with poor retention of energy (bit's of spring, thin aluminum body, etc). This
provided a safety feature (somewhat...) in the the tiny light bits would not maintain driving energy, etc. Their distance for lethality diminishes.
[Authors; Person and] several others authors had mentioned the vital important of safety shielding, light weight, and extremely light
containerization. Once a weight level is reached in a high explosive the blast alone becomes a serious danger, yet if the material is kept low in
weight and the container has minimal energy retention characteristics, the level of danger is somewhat less than ignoring those factors.
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Isn't some of the energy going to escape between the wires, while the iron is expected to balloon uniformly and achieve greater energies?
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Fantasma4500
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found this video
not sure how much they fill in landmines... its a IED apparently, so nobody can know for sure but it looked somewhat like 500g
https://www.youtube.com/watch?v=GlN1qDoTAp4
puts some pictures to the word ''fragments''
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Fantasma4500
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''Fuller account:
I was about the age of many of our newer members... Old enough to drive & buy alcohol, not old enough to know I was mortal. This was BEFORE I got
involved with display pyrotechnics & special effects professionally.
Alcohol WAS involved. I learned my lesson, you may have a beer or handle energetic materials/weapons, not both.
My face wasn't really bruised, but my abdomen and chest were- The parts closest to the explosion and directly facing the source. I had a full beard at
the time and needed to trim it off as the bottom part on the left side was kind of half melted. I had short hair, my left cheek and forehead had the
beginnings of a 1st degree burn- Pink and felt hot for a day, but didn't lose the skin.
Scenario:
Finished a hot, sweaty project of cutting up a large rusted out water tank too big to move in 1 piece without heavy equipment, using a borrowed
cutting torch and rented gas bottles. The work site was a vacation home on an island, with no one else around.
Put away the torch and cracked a beer to celebrate being done. It was such a waste to return the bottles still partly full, or so it seemed after the
2nd beer... So the torch came back out, along with a roll of kitchen garbage bags and some "visco" fuse.
The largest welding head was set to the leanest possible setting, just short of "torch pop", extinguished by tapping against a wooden plank and then
inserted into the bag. When the bag was full, top was tied in a knot and a nice long piece of visco was taped against a corner of the bag. Bag
positioned against a boulder facing out over the river, I knew enough not to do this with direct line of sight to the windows of the house.
I was still wearing my work outfit of blue jeans, boots, long sleeved heavy cotton welder's shirt, and glasses fortunately.
Bent over to light the fuse, straightened up and started to turn to my right and run- Then I was in the river, treading water within arms reach of the
bank. Don't remember getting there. Climbed out. The world is a little odd looking, kind of blurry. Nothing but a high pitched tone in both ears, no
wind, waves on the shore or insect noises heard. Then I noted the blood coming out of my nose and things "clicked" back into focus. My glasses were
still in the river.
It was about 45 minutes by boat to the nearest town with a hospital and emergency room, so I put on dry clothes and headed there. The staff were quite
surprised when I told them I'd blown myself up with welding gas- The ER intake guy said, "Oh, when we get a welder in here, he usually dies".
They did a full chest X-ray set when they saw my chest, but found no broken ribs. Looked in the ears, rinsed out the river water and gave me oral
antibiotics & some ear drops, along with a can of some soft waxy stuff to plug my ears with while showering. No more swimming for the rest of that
summer.
Both ear drums eventually closed up again, the right in about a month, it took nearly 2 months for left (the side towards explosion). I don't require
hearing aids for my commercial drivers license, though my hearing IS permanently degraded, especially high frequency responses. If I set the sound
system up, no one else likes the bass/treble balance... '' -Anonymous
to get away with an experience is never a bad thing, in my opinion, however the victim had permanent hearing damages..
i would never expect such power from acetylene mix, to get straight up knocked out.. always be insanely careful when handling fuses near gas
mixtures..
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