Wapsi Square Forum

zachariah wrote:Not an interesting day. Nightmares. The only way to dispose of something like this is buffer it in place and blow it. For that they would need approval up the chain. How long would that take? Meanwhile they get to sit there praying that nothing happens.

Yup... "interesting" in the sense of the old Chinese curse, "May you live in interesting times."

Occasionally you hear stories of somebody who has an accumulated stash of old explosives like this in their home or garage... survivalists, war-souvenir collectors, crazy amateur chemists or pyotechnicists, "mad bombers", etc. In most of the cases I've heard about, the bomb experts do make an attempt to extract the stuff in smaller quantities (sometimes with robot material handling systems) and detonate it a piece at a time... less overall damage to the neighborhood. In touchy or extreme cases, though, it's just as you say... BOOM.

I saw a video of one case in which they decided that the least risky thing to do was to evacuate the neighborhood and torch the building... try to get as much as possible of the less-unstable stuff to combust before anything actually went bang. Conflagration rather than detonation.

Well...This is where we sit back and enjoy the fireworks, right?

Mark N wrote:

Jay-Em wrote:Oooohkay..

two possible outcomes:

1. When the fuses are near-by, or already in some of the dynamite: "Kablooi",big badaboom.
2. When not, it's just suffocating and/or burning to a crisp.

Where's a "poiter" when you need one?

One problem with your assessment, old dynamite will have sweat nitroglycerin. This is extremely sensitive to temperature variations and fire is rather high on the temperature variations. So we must expect an Earth shattering KABOOM.

(Drops a vintage Marvin the Martian toy in the pun vault and runs like Hell)

Came for the "Earth Shattering KABOOM" was not disappointed. However it might be more appropriate tomorrow!

Fairportfan, you made an oopsie with the date in the thread title.

Dave wrote:

zachariah wrote:Not an interesting day. Nightmares. The only way to dispose of something like this is buffer it in place and blow it. For that they would need approval up the chain. How long would that take? Meanwhile they get to sit there praying that nothing happens.

Yup... "interesting" in the sense of the old Chinese curse, "May you live in interesting times."

Occasionally you hear stories of somebody who has an accumulated stash of old explosives like this in their home or garage... survivalists, war-souvenir collectors, crazy amateur chemists or pyotechnicists, "mad bombers", etc. In most of the cases I've heard about, the bomb experts do make an attempt to extract the stuff in smaller quantities (sometimes with robot material handling systems) and detonate it a piece at a time... less overall damage to the neighborhood. In touchy or extreme cases, though, it's just as you say... BOOM.

I saw a video of one case in which they decided that the least risky thing to do was to evacuate the neighborhood and torch the building... try to get as much as possible of the less-unstable stuff to combust before anything actually went bang. Conflagration rather than detonation.

It is as you say. They do try if it is not too old and the area makes blowing it difficult or expensive. The robot is what allows them to do it as anyone of them would refuse to try it in person. Luckily it doesn't happen often and usually not in densely populated areas. But how many times does the robot actually manage to get it all out? They could loose a lot of robots that way you know. lol.

Dave wrote:

zachariah wrote:Sorry but there is no nitro in TNT. It is a different compound entirely.

They're different chemically, but are fairly close "cousins".

TNT is tri-nitro-toluene.
"Nitro" is tri-nitro-glycerine.
EGDN (a related explosive) is ethylene glycol dinitrate (or di-nitro-glycol if you prefer)

They're made via the same basic chemical process (nitrating the organic starting material using nitric and sulfuric acids) and store energy within the molecule via bonds involving nitrogen atoms. All of them go boom quite nicely when suitably encouraged.

Just as apples and oranges are cousins. Not worth arguing about. You are correct about the nitrogen bonds being what supplies the exothermic reactions that cause the explosive effect. The major difference is always the propagation speed of the reaction. At this point everyone is now going TMI!!! So I will be quiet from here on. But this discussion was a blast.

Drops 2 grams of burning C4 into the pun jar for it to heat it's tea with.

Wapsi wrote:In regards to today's comic, it's good to see that a few readers have done their research as well. No dynamite will not explode if thrown in a fire, that's the purpose of the gun cotton that is mixed with the nitro, at that point it needs a supersonic shock of a blasting cap. However, dynamite that has been sitting for 100 years will "sweat" all the nitro to the surface and it crystallizes. At that point, if you sneeze, it goes "boom". Fire pisses it off and it still goes "boom".

Guncotton (nitrocellulose) is about as unstable as nitroglycerin. Mixing the two somewhat stabilises both (this is what "double base" smokeless powders are made from).

An other binder is required to make dynamite (the most modern double-base explosives apparently use ketone, which is an organic solvent that, i suspect, plasticises the guncotton) - the original dynamite was essentially fuller's earth soaked with nitroglycerin.

Interestingly enough, most if not all of what we see in the comic is quite possibly not nitroglycerin-based:

Wikipedia wrote:In the United States, in 1885, the chemist Russell S. Penniman invented "ammonium dynamite", a form of explosive that used ammonium nitrate as a substitute for the more costly nitroglycerin. These dynamites were marketed with the trade name "Extra". Ammonium nitrate contains 85% of the chemical energy of nitroglycerin. Dynamite was manufactured by the E. I du Pont de Nemours Company until the mid-1970s. Other American dynamite makers of that time period included the Hercules Corporation, Atlas, Trojan-US Powder, Austin, and several other smaller firms. Dynamite has been mostly phased out in favor of water gel explosives, which are cheaper to manufacture, and in many ways safer to handle.

There's a later type (also invented by Alfred Nobel), called "gelignite". It apparently reduces or eliminates the sweating problem

zachariah wrote:

Sphinx-Napped wrote:

Wapsi wrote: yep it does, althought the 100 year old boxes on tnt was just a added bonus to my prediction

It's not TNT. That was developed during WWII. Then became the first plastique I think. TNT does not sweat, it will burn and not go off, and stores very nicely for long periods of time. Dynamite on the other hand is a very different thing. When it sweats it becomes more unstable that a third world dictatorship being run by Schroeder's cat.

I have a friend who does WWII Living history displays and has quite the demolition display... he has a lot of fun with it after spending 28 years in the army before retiring, it's his way to keep in the military mind set and teach history at the same time. He has a habit of joking around, pronouncing Dynamite "deenameetay". LOL I can say that I've learned quite a bit from him on the subject. As stated here previously, Dynamite is Nitro Glycerin absorbed by silica or sawdust and wrapped in cardboard cartridges. TNT is "Tri-Nitro-Toluene". RDX is Royal Demolition Explosive. Plastique refers to explosives such as Composition 2, C-3 or C-4, Composition B, RDX or Pentolite which have stabilizers and plasticisers added to help stabilize the explosives. These plasticisers make the explosive more stable to handle, but also more malleable like modelling clay. Being more stable, the explosive requires a shock, rather than flame to detonate. Hence, you can cut off a chip of C-4 and light it and it will burn. Just don't stomp on it to put out the flame... While dynamite can be set off by a burning fuse, (it was most often used as a heaving agent, imparting a slow shock to the rock being blasted, blowing off large sections of the rock. Higher orders of explosives such as TNT or any of the "C" explosives were used to impart a much greater shock force which would literally shatter the rock.) TNT, the "C" explosives, RDX and pentolite require a blasting cap to detonate.

Wapsi wrote:...dynamite that has been sitting for 100 years will "sweat" all the nitro to the surface and it crystallizes. At that point, if you sneeze, it goes "boom". Fire pisses it off and it still goes "boom".

Soooooo, how sensitive is is crystal nitro to an ear-splitting scream?

DilyV wrote:While dynamite can be set off by a burning fuse, (it was most often used as a heaving agent, imparting a slow shock to the rock being blasted, blowing off large sections of the rock.

Nope. You can toss most dynamite in a fire and it won't burn. (Assuming it is neither sweating or capped.)

it requires a shock - such as a blasting cap - to set it off.

Also, dynamite is a fine shattering agent - it will break rock or concrete if detonated on top of it. Using it as a heaving agent requires drilling shot holes and placing the charge well into the rock to be broken up.

Higher orders of explosives such as TNT or any of the "C" explosives were used to impart a much greater shock force which would literally shatter the rock.) TNT, the "C" explosives, RDX and pentolite require a blasting cap to detonate.

Nope again.

A blasting cap is a small sensitive primary explosive device generally used to detonate a larger, more powerful and less sensitive secondary explosive such as TNT, dynamite, or plastic explosive.

Also, dynamite is a higher-energy explosive than TNT (About 1.25 times; dynamite yields 5 Megajoules/kg, TNT only 4).

=================

My Dad was an ordnance tech in the Air Corps in World War Two - he said that one day the instructor came in with a block of what looked like putty or something.

He stopped by his desk, without saying anything, then threw it as hard as he could against a wall.

Then he picked it up, put it on his desk, lit a cigarette, and used it to melt a couple of holes in the stuff.

Of course, by this time, the class was like "Whiskey Tango Foxtrot Interrogative".

The sergeant sat down, put out the cigarette, poked the stuff on his desk...

And said "This is TNT."

Interestingly enough, most if not all of what we see in the comic is quite possibly not nitroglycerin-based:

Wikipedia wrote:In the United States, in 1885, the chemist Russell S. Penniman invented "ammonium dynamite", a form of explosive that used ammonium nitrate as a substitute for the more costly nitroglycerin. These dynamites were marketed with the trade name "Extra". Ammonium nitrate contains 85% of the chemical energy of nitroglycerin. Dynamite was manufactured by the E. I du Pont de Nemours Company until the mid-1970s. Other American dynamite makers of that time period included the Hercules Corporation, Atlas, Trojan-US Powder, Austin, and several other smaller firms. Dynamite has been mostly phased out in favor of water gel explosives, which are cheaper to manufacture, and in many ways safer to handle.

One of the reasons that the various dynamite manufacturers went out of business was the mining industry's wholesale switch to ANFO (ammonium nitrate and fuel oil) which is far cheaper and safer.
That's not to say the girls are not in danger, far from it, but the additional stability of the Extra dynamite may give them the lead time they need to get back to the library, or if they are too far away, to take shelter in the mine cart.
With enough distance they may simply be blown out of the mine by compressed air, although I sincerely doubt they will be returning home the same way.

sheik wrote:Interestingly enough, most if not all of what we see in the comic is quite possibly not nitroglycerin-based:

Aha! Thank you - I had entirely missed the implication of the trade term "Extra" on the boxes in the mine. That does render a lot of our previous discussion moot.

One of the reasons that the various dynamite manufacturers went out of business was the mining industry's wholesale switch to ANFO (ammonium nitrate and fuel oil) which is far cheaper and safer.
That's not to say the girls are not in danger, far from it, but the additional stability of the Extra dynamite may give them the lead time they need to get back to the library, or if they are too far away, to take shelter in the mine cart.

Yes, I'd expect ANFO to have better long-term stability than a nitroglycerine-soaked matrix.

But, as you say, they're not out of danger. If somebody stored any blasting caps in or near that pile of crates, things could turn very bad very quickly.

If anything, the fact that that Extra "dynamite" is old could make it even more powerful. The ammonium nitrate is probably just the way it was, but the oil may have been altered with time... and, as we know, there's no fuel like an old fuel.

(drops a can of hundred-year-old gasoline into the Pun Jar... "Aesop" brand, of course)

Old DuPont 'self-help' materials from a simpler time:

I don't think anyone would keep blasting caps anywhere NEAR where you'd store dynamite, but that's just...


BOOOOOOOM

"What the.... Why is the pun vault suddenly 1,000 feet in the air, and attempting to gain orbital velocity?..."

MrBill wrote:Old DuPont 'self-help' materials from a simpler time:

Nice! I'll bet a fair bit of that is probably still applicable today: stump removal, boulder destruction, creation and dredging of cattle-watering ponds, cracking bedrock to install pilings for outbuildings, and so forth. "How to make holes and influence shrapnel, without really trying."

A bit like "Operation Plowshare" on a much smaller scale

MrBill wrote:Old DuPont 'self-help' materials from a simpler time:

Heh. An ad for essential farm/ranch equipment:

interesting that we are sitting around discussing the chemical composition of the boom that is about to happen and using this to judge how big a boom there's going to be. All i can say is that anyone in the immediate vicinity (such as within 10-15 feet) will be vaporized no matter how big of a boom there is.

displaced wrote:interesting that we are sitting around discussing the chemical composition of the boom that is about to happen and using this to judge how big a boom there's going to be. All i can say is that anyone in the immediate vicinity (such as within 10-15 feet) will be vaporized no matter how big of a boom there is.

Try 100 to 150 feet with that much in a tunnel. The blast will be channeled initially until the rock fractures.

zachariah wrote:

displaced wrote:interesting that we are sitting around discussing the chemical composition of the boom that is about to happen and using this to judge how big a boom there's going to be. All i can say is that anyone in the immediate vicinity (such as within 10-15 feet) will be vaporized no matter how big of a boom there is.

Try 100 to 150 feet with that much in a tunnel. The blast will be channeled initially until the rock fractures.

Unless someone has a new power to play with at least.

DilyV wrote: Hence, you can cut off a chip of C-4 and light it and it will burn. Just don't stomp on it to put out the flame...

MythBusters disproved this a couple of years ago by setting C4 on fire and using a "stomping robot" to try to make it explode, then actually stomping on burning C4 themselves (I think it was Adam rather than Jaime). Eventually they even tried using explosive bullets to try to make burning C4 explode and nothing short of a blasting cap would set the stuff off.