7 ms·
“Off switch” makes explosives safer
- exabrial 4y ago> They used a 3D printer to produce...... Wow really upping the pucker factor in one of my favorite hobbies.
- smilespray 4y agoTip: Don't heat the print bed when printing with TNT.
- nibbleshifter 4y agoIts melt castable and not the easiest thing to get going, so you probably could print with it. Probably would also give you megacancer.
- wongarsu 4y agoApparently TNT melts at 80°C. If we are to believe [1], liquid TNT is quite sensitive while confined, and gets more sensitive the hotter it gets, but if allowed to flow it's actually very difficult to set off. Autoignition happens at about 265°C, according to [2], and again according to [1] temperature doesn't play a major role in the sensitivity of solid TNT. So I guess don't heat the print bed too much, and if you do make sure the TNT can flow freely until it solidifies again, and you should be fine. Edit: and as nibbleshifter suggests, you could print with it given these parameters, just be careful with the TNT in the hotend. 1: https://www.cdc.gov/niosh/mining/userfiles/works/pdfs/itass.pdf https://www.cdc.gov/niosh/mining/userfiles/works/pdfs/itass.... 2: https://www.govinfo.gov/content/pkg/GOVPUB-C13-36e8df81dfe031f3f6861501d4a96cfa/pdf/GOVPUB-C13-36e8df81dfe031f3f6861501d4a96cfa.pdf https://www.govinfo.gov/content/pkg/GOVPUB-C13-36e8df81dfe03...
- dsfyu404ed 4y agoWould be pretty cool to be able to order custom shapes SendCutSend style. Would be real useful in demolition and construction settings in cases where you don't do enough of a specific job to buy or rent expensive non-explosive equipment to do it.
- TylerE 4y agoThat's easy with plastic explosive. It's a putty like consistancy. It's explicitly designed to be sized and shaped in the field.
- Arrath 4y agoThere are to this day many an explosive product that is cast by pouring molten explosive material into the shell. In some cases, poured by hand from jugs. Steady!!!
- jabl 4y agoI recently read about the Oppau disaster (https://en.wikipedia.org/wiki/Oppau_explosion https://en.wikipedia.org/wiki/Oppau_explosion ), where the workers were getting bored with using pickaxes to break up a huge pile of compressed ammonium sulfate and ammonium nitrate, and decided to use dynamite to loosen it up. What could possibly go wrong?
- jandrese 4y agoThe crazy thing about that is they had broken up the Ammonium Sulfate/Ammonium Nitrate mixture thousands of times before the incident. It was incredible that they managed to do so for as long as they did. All it took was one day where the mixture wasn't mixed very well and everyone dies. An industrial version of Russian Roulette.
- Xylakant 4y agoIt was considered safe at the time because the mixture is usually not very sensitive. Hindsight is 20/20.
- Someone 4y ago> It was considered safe at the time I know they thought so, but also wonder why they thought so. Yes, https://en.wikipedia.org/wiki/List_of_ammonium_nitrate_disasters#Timeline_of_major_disasters https://en.wikipedia.org/wiki/List_of_ammonium_nitrate_disas... says: “the factory had used this method of disaggregation over 20,000 times without incident” But it also mentions what happened less than two months before the Oppau explosion: “July 26, 1921: workers tried to dislodge 30 tonnes of ammonium nitrate that had aggregated (solidified into one mass) in two wagons. When mining explosives were used on this solid mass the wagons exploded and killed nineteen people” Separation between the two disasters is about 1,000 km, but both were in Germany. Surely, they must have heard what happened there. Why didn’t that make them reconsider using this technique? And why didn’t that second explosion prevent what happened in Tessenderlo in 1942 “An attempt to disaggregate a pile of 150 tonnes of ammonium nitrate with industrial explosives killed 189 people and wounded another 900”? That’s about 300km, as the crow flies, from Oppau.
- flangola7 4y agoYou wouldn't download a shaped charge
- dtgriscom 4y agoAnybody want to go to http://thingiverse.com http://thingiverse.com and search for "shaped charge nuclear detonator"? Extra points for doing so with cookies enabled.
- Animats 4y agoSafe until filled with water is probably not that useful. Water is everywhere and things in military use tend to get wet. There are binary explosives now, where both components are nonexplosive by themselves. Those are used commercially, for road work and such.
- londons_explore 4y agoDepends how it's designed. If it needs to be drenched to be explosive, then simple drains holes at the bottom keep it safe. Plug the holes and fill with a hose when you want to use it.
- andrewflnr 4y agoYeah, damp or drizzle isn't going to activate these, if I'm understanding them correctly. If anything, I was wondering at first how they were going to deal with air bubbles (but I suspect they're fine as long as there aren't too many).
- exabrial 4y agoAh, yes, but think those olive drab steel Ammo Cans. These are a simple, cheap, tried-and-true tested method of preserving military supplies; heat proof, water proof, dust proof, (somewhat) nuke proof, biological proof, and fire proof.
- dtgriscom 4y agoVery off-topic, but I have to relate this incident. I was hitchhiking up the US East Coast in the spring of 1983, and stopped in Washington, D.C. While there, I picked up an ammo can from a Army Surplus store (it seemed cool, never used it for anything, still have it). While walking around DC I met a guy who worked in the Capitol, and he invited me into his building. At the entrance, there was a security post checking bags. They patted down the sides of my backpack, but never even looked inside the ammo can. I guess it was too obvious.
- tomatotomato37 4y ago
- chillingeffect 4y agoThose are the names of Javascript libraries right?
- Kon-Peki 4y agoIf such a thing can be scaled and made reliable, the implications are staggering. Imagine ammunition that fits in existing firearms and is fully self-contained, mixing into a viable round only when entering the chamber. And then made “smart”, such that it can be geofenced and therefore refuse to mix near schools or stadiums or government buildings, etc. If this becomes possible, then all traditional ammunition may become legislated or litigated out of existence.
- throwanem 4y agoThat would require a battery, a GPS chipset, and either a sizable database or a cellular radio, in the base of every cartridge. I'm pretty sure ammo makers aren't shaking in their boots on this one.
- TylerE 4y agoYou could probably do it with something like Bluetooth LE in the bullet. You'd need some sort of base station, worn on a belt loop or something. Binary explosives certainly exist so it should be in theory possible. Not sure how well they "scale down" though, and I don't know if any have a blast velocity low enough to be workable. I'm not a gun guy, really, outside of my interest in naval warfare. 16" shells have slightly different design params though. Actually, thinking about it more would the barrel act like a faraday cage?
- throwanem 4y agoIt would make considerably more sense to use standard ammunition and conditionally release the firing pin based on logic in the firearm, but to be clear this is all still well within the realm of flagrant silliness, to the point where if n-gate (pbuh) were still around this thread would probably qualify as bait.
- runnerup 4y agoAmmo is really really safe as it is. Ammo doesn’t accidentally go off. The modifications you’re talking about would go on the gun, not the ammo.
- A4ET8a8uTh0 4y agoLoved the read. I know I am on a list somewhere now, but I don't care. This is what HN is all about. Interesting knowledge.
- killjoywashere 4y agoAh, Los Alamos, exactly what I though. What this really is, is an external manifestation of the eternal struggle between the military, which wants the weapons to detonate on time every time, and the safety-minded engineers and politicos who would rather eat an occasional fail than start a nuclear war. The safety people being the engineers tend to keep finding new ways to be safe and applying them without necessarily securing the DoD’s permission, but they don’t always work out the way the engineers intended. For a period of time, there was a piece of cobalt tape on Trident missile warheads that would ensure they fizzle unless removed. Except the adhesive dried up and then the release force exceeded the torque of the motor intended to remove the tape, so something like 75% of the Trident missiles were duds for years. Read Eric Schlosser’s Command and Control. Absolutely fascinating.
- jabl 4y ago> the military, which wants the weapons to detonate on time every time Well, the military sure is also concerned about avoiding non-intentional detonations due to accidents or by being hit by enemy fire. E.g. the IMX series of explosives that have apparently started to replace TNT and Comp B in some applications. https://en.wikipedia.org/wiki/IMX-101 https://en.wikipedia.org/wiki/IMX-101
- KptMarchewa 4y agoAs we've seen in Ukraine, sensitive munitions kill a lot of tank, IFV and artillery crews.
- rtkwe 4y agoPart of that is the design of Russian tanks as well. Because of the design of the autoloader they use the turret has to sit on top of the shells in Russian tanks. Other countries use a human loader that puts the shells in an armored box with intentional weaknesses so any fires or explosions have a safer direction to expand than into the crew compartment.
- 4y ago
- EamonnMR 4y agoWater has a tendency to get into places it's not supposed to. I'd hate for a roof leak to cause a warehouse explosion.
- loufe 4y agoI work as a drilling and explosives engineer at an active mine. I don't see the value-add here, to be honest. Modern explosives management (in a mining context) is extraordinarily well managed. ANFO (ammonium nitrate fuel oil) which is the dominant explosive type is so hardy that you can hold a flame to it or shoot it with a firearm and you will not succeed in detonating it. 3-stage explosives systems (detonator-->booster-->ANFO) is a fantastic way of managing risk. Detonators cannot set off ANFO, the booster is required middle step. I won't pretend to have studied the phenomenon, but the only undesired detonations I've heard of so far in my career have all been a result of detonators inadvertantly set off. The latest examples I know of being wireless electric detonators (which are being phased out as they're inferior to electronic detonators,which offer more protection) set off because of malfunctioning devices emitting the required radio waves, yikes! The explosion in Beirut can hardly be considered in the same category as that was an explosion of explosive precursor, effectively unrelated. I'm struggling to understand what the target market for this type of innovation is. Is it bulk transport of explosive materials between the manufacturer (like Orica or Dyno-Nobel) and individual mine sites? That part is already extremely safe. You'd need specialized equipment at each mine to mix the water back in, with maintenance and calibration requirements. There's no way this could be between the surface and the holes into which the explosives are loaded, for so many reasons. I also wonder about the consistency and quality of the resulting product, the balance for these explosives is already such a tuned and precise.
- WatchDog 4y agoThere are a number of very high-profile accidents with ammonium nitrate[0]. It can be detonated without a detonator+booster, although the mechanism isn't well understood, seems like in a fire it can form more volatile compounds with soot and other contaminants. Still, I would agree, it's generally a very safe compound. It's handled every day in enormous quantities. [0]: https://en.wikipedia.org/wiki/List_of_ammonium_nitrate_disasters https://en.wikipedia.org/wiki/List_of_ammonium_nitrate_disas...
- SOLAR_FIELDS 4y agoGood call out. It’s generally very safe, but when it goes wrong, it’s catastrophic. Grandparent’s comment feels out of touch - looking at it from another lens: flying is generally safe but there is a certain unique set of circumstances that cause catastrophic failure and plane crashes. Do you just ignore the process and materials improvements because that certain set of events is super rare? No, you include the improvement in your process. That attitude has allowed FAA and Airlines in general to become much safer over the past 40 years (1). 1: https://www.bts.gov/content/us-general-aviationa-safety-data https://www.bts.gov/content/us-general-aviationa-safety-data
- GartzenDeHaes 4y ago> in the military world, for example, over 500 accidental explosions occurred at munitions sites between 1979 and 2013, according to a survey This is false in the US and NATO. The study they site is counting incidents in Albania, Bosnia, Croatia, Montenegro, Serbia, and Slovenia. https://www.jstor.org/stable/resrep10678?seq=2 https://www.jstor.org/stable/resrep10678?seq=2
- zzzeek 4y agosafe unless submerged in water! Great. It's of course incredibly unlikely for unattended store rooms to ever be exposed to this unusual substance that occasionally falls from the sky and fills up entire towns.