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hcrof

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Posts posted by hcrof

  1. I think anyone asking Ukraine to rely on drones for victory has missed that the gap in drone use efficiency has closed considerably . They are still better but the Russians have got competent, and have greater numbers. 

    Even if they crack drone autonomy I hope they are able to take advantage of it quick because the Russians might not be far behind. 

    I believe the Ukrainian path to victory is now 100% on the russian home front, not victory on the battlefield. Unfortunately it won't be quick...

  2. 30 minutes ago, kimbosbread said:

    If each mortar bomb weighs 4.5kg, and each drone weighs the same, and the drones have some basic last-mile autonomy (which we already seeing), is there any reason to belive the drones can’t deliver the same volume of fire, but with much more accuracy and range, but a much smaller logistical footprint?

    You might be right tbh, when drones become mature enough. But I would hedge if I were purchasing right now, maybe that drone counterswarm arrives? Or better counter-ai camouflage? But then hedging would also mean not purchasing that fancy new mortar! I'm glad I don't have to make those decisions...

  3. 33 minutes ago, Battlefront.com said:

    Right, but one of the reasons for the high RoF is because the chances of any one shell having the desired effect is rather low.  Again, mass vs. precision.

    One of the things we've always hammered into our CM customers for the past 25 years is that mortars and MGs are there for suppressive effects first, killing effects second.  The idea is you hit an attacking company with a bunch of mortar rounds or MG fire and you disrupt their attack, perhaps to the point of forcing it to retreat.  We've seen that one or two FPVs have the same effect and possibly even the same, maybe even better, killing effect.

    It's like snipers in the real world.  Shoot a single bullet and hit a single man in a 9 man squad and you have an impact on that squad's performance disproportional to the one man shot.  Perhaps even more impact than a couple of mortar rounds dropping by or a spray of MG splash on their position.

    Steve

    I agree, but snipers don't make machine guns obsolete! Sometimes you have an "oh crap" moment where you need a lot of fire very quickly, and mortars do that very well. I think there is space for both, although in the modern battlefield the mortar may need to be attached to a vehicle of some kind so it can displace quickly. It doesn't all have to be an 8x8 either (although those are great), there are lighter versions like scorpion.

    My vote though, would be a ugv version, to make it even smaller and easier to hide. Like a pair of universal carrier sized vehicles: one with a mortar on the back and the other with the crew and extra ammo. 

  4. 9 minutes ago, kimbosbread said:

    Yeah that’s fascinating. I guess the tradeoff for an 80mm mortar (M252) goes something like this:

    • Mortar
      • Mortar itself weights 40kg
      • Bombs weigh 4.5kg
      • Max range is 6km
      • Crew of 5
      • Big boom on firing
    • FPV drone
      • Juicy version has 1kg HE (plus LIPO juicyness); other version has a couple of AGL grenades or whatnot.
      • ~4kg total weight
      • 10+km range
      • Crew of 1-2
      • Very precise
      • No noise on launch
      • EM signature

    Seems pretty clear cut. I wonder how the equation changes for a mortar hauled around by an UGV. Does that make the extra weight worth it? Presumably precision mortar bombs cost more than an FPV too.

    EDIT: This is without relays and/or some form of autonomy. With those, range goes up and signature goes down.

    You gotta also differentiate between propulsion: Propellor, turboprop, turbojet, turbofan, solid-fuel rocket etc, and/or combo with glide phase. Each of those are pretty different in terms of how to detect them.

    On the power source you also have fuel cells, which sound very cool, but are less practical than batteries IMO.

    The big advantage of a mortar is the rate of fire, so a small number of mortars can potentially do a lot of damage. But the rest of your points are valid.

    There are some interesting videos of the British army mortar teams being very creative with camouflage. For example hiding it in a dumpster or inside a wrecked building, so when the drones come hunting they can't find it. Whether that works in practice remains to be seen. 

  5. 30 minutes ago, A Canadian Cat said:

    This where I see an issue with autonomous drone usage - namely friendly fire and civilian casualties. I'm not sure how big the issue will be, that will be based on how these automatic targeting systems work. Friendly fire or killing of civilians could be a serious problem with autonomous drones if this isn't handled well / correctly.

    The comparison to the Navy CWIS autonomous systems doesn't really work because there is a clear exclusion zone around fleets and warships to the point that if some civilian wondered inside that area they would get no sympathy when they get whacked. So, those systems can be weapons free and autonomous for certain ranges without risking civilian or friendly casualties. In other words humans have managed the space those autonomous systems work in so that they can target anything that comes with in them "safely".

    Autonomous drones hunting enemy soldiers, tanks and other vehicles do not have that kind of space. They have to operate in a much messier and chaotic environment. Lots can be done, make the targeting smarter, geo-fencing, range cut offs etc. but the issue is none of that is as clear cut as "get within 100m of a destroyer you die".

    All of those problems have solutions of varying degrees of effectiveness some of which can now be attacked (geo-fencing really should not be relied on for this) or have short comings that have unknown or known failure points (targeting only enemy AFVs is not actually easy and since these systems are actually trying to kill people that problem is more important to deal with).

    I'm not saying there will not be autonomous drones or that we should try to ban them. I don't think we can do that. I am saying that these systems are going to have problems that human controlled systems don't. Or perhaps a better way of saying it would be they are going to have different failure issues and those failures are going to hit the public's ear differently and that needs to be managed.

    Or not I suppose :D 

    The way I see it is that if you bombard and area with artillery then everything in an ellipse of hundreds of meters is at risk of dying. I don't see much difference in designating a killbox for drones and letting them go for it. In fact a killbox is better since it can be defined more precisely and the stroke can be closer to your own troops. 

  6. Since this discussion doesn't seem to be stopping I want to say that both sides need to cut each other some slack. What consenting adults do with each other is none of my business and if my friends or family have a same-sex relationship it does not harm me in any way. 

    On the other hand some people are uncomfortable with that and they are not going to change their mind by your disapproval. They just need time and space to realise the whole country isn't going to burn down because some man decides to wear a dress or something. 

  7. On 4/3/2024 at 8:53 PM, Erwin said:

    https://www.wsj.com/world/europe/ukraine-in-need-of-troops-lowers-age-of-conscription-2d67844e?mod=world_lead_pos4

    "Ukraine lowered the age of military conscription to 25 as part of an effort to bolster its depleted armed forces after two years of fighting Russia’s invasion and facing renewed assaults. The controversial bill, which President Volodymyr Zelensky signed into law on Tuesday, is the most significant overhaul of Ukraine’s war bureaucracy since Russia’s full-scale invasion began in February 2022.

    Men between 18 and 60 have been prohibited from leaving the country since the start of the war, but only those who were at least 27 were eligible to be drafted. Zelensky’s backers and some opponents said the bill had been delayed because it was unpopular.

    The change comes as Ukraine’s defensive lines come under heavy pressure from massive Russian assaults. Front-line commanders say they are short of personnel and ammunition, as a supplemental aid package is stuck in Congress. Ukrainian officers say they are expecting Russia to mount a significant offensive around the start of the summer, which is aimed at expanding the nearly 20% of territory the invading forces already occupy."

    This seems bizarre, as that means Ukraine is conscripting men (are women being conscripted as well?) who are likely have families, careers and other responsibilities.  Usually its the 18-22 years old who get sent to the front.

    Just found this thread. The Ukrainian government has been able to put off difficult decisions for too long because of the stalemate at the front. It's not like the russian narrative of the male population has been emptied from the country, it's more like trench warfare is dangerous and unglamorous so no-one wants to do it. But there isn't an existential sense of crisis in the country so the can is kicked down the road. 

    If the Russians actually made meaningful gains I wouldn't be surprised if there was a rush to the recruitment offices. 

  8. 7 minutes ago, Ts4EVER said:

    I mean obviously NATO can easily outspend and outproduce Russia, at least long term, but is this actually going to happen? It seems the political will to do that is not that secure.

    Russia is spending over 6% of it's GDP on the military right now, which is a very heavy burden. A handful of NATO countries spent a comparable amount of money in Afghanistan every year for 20 years without much effort. 

    I have not got the numbers to hand but NATO is not breaking a sweat right now financially, so even if big players like the US pulled out (doubtful, even with trump in charge IMO) they still have the resources to keep going. In a few years industry will catch up to the financing and then NATO can supply Ukraine indefinitely. 

  9. 31 minutes ago, Ts4EVER said:

    But logistically, isn't Russia still in advantage?

    Depends on if you isolate the war away from the west's support of Ukraine. Lots of Russia supporters don't/can't grasp that even if Ukraine can't win outright, it won't lose as long a even a few western countries keep the flow of supplies going. I don't think Russia has a plan for that. 

  10. 28 minutes ago, Hapless said:

    @dan/california Seen as though I was eyeballing it.

    Having to re-read it to edit this post down only makes it sound crazier.

    Yeah, he obviously doesn't know the history of Afghanistan or Czechoslovakia/Hungary or he would be making that comparison not Iraq 2003. He kinda says that if war was a computer game you could save-scum your way to a flawless victory against impossible odds. But he doesn't say how. 

    War is about mistakes - you can't run a "what if" scenario based on your side running a flawless campaign with perfect knowledge of both thr enemy and yourself

  11. 5 hours ago, Battlefront.com said:

    Impossible to say.  He has a pretty neutral American accent.  Common for both northeast and westcoast, but not limited to those two VERY densely populated areas.  As for ethnicity, no clue but I'd guess mixed parents and at a minimum raised in the US.  One of the things that's difficult with Americans is it is very common for mixed parents to be themselves from a mix.  America is the "melting pot", after all!  If I had to guess I'd say one of his parents has strong Middle Eastern heritage.

    The things he said were very repetitive and not very interesting. 

    Steve

    https://meduza.io/en/feature/2024/04/04/pro-kremlin-telegram-channels-share-propaganda-video-featuring-u-s-city-councilor-who-joined-russian-army-after-fleeing-child-pornography-charges

    No suprise that he is on the run from US law enforcement...

  12. 35 minutes ago, Battlefront.com said:

    I agree, I don't think this will disrupt production for very long.  And if this was only 1 of 3 factories it won't disrupt it at all, though the number used per attack may be reduced.  All of that is good and well worth the expense of one long range drone.  Still, it's not an answer on its own.

    The thing about all these attacks is that no single attack has much impact on how the war is going today.  Even sinking a ship doesn't.  However, cumulative and over time they matter.

    Earlier in the war we had Ukraine blowing up railroad bridges and switching stations.  Everybody cheered, but they were quickly repaired.  The next hope was that Ukraine could knock them out faster than Russia's repair capacity could fix them.  This seemed a long shot and it is probably why Ukraine has switched to other targets. Something with inherently more concentrated and more difficult to replace/repair.  More costly too.

    The attacks on the oil/gas industry are not yet having a noticeable impact on the war, but they are a great thing to concentrate on.  There are a limited number of targets, they don't move, due to size and vertical nature they are easy to hit, they are insanely expensive to repair, some components are difficult for Russia to replace, and there's only so many qualified construction crews and engineers to fix things at any given time.

    Steve

    Agreed. The wider the radius Ukraine can strike, the area Russia needs to cover with air defence goes up by that number squared. If nothing else it is an expensive distraction having to defend such an enormous area. 

    It is a puzzle to me why Ukraine chooses not to increase the number of strikes. Maybe they think that money is better spent elsewhere, maybe they don't want to mobilise russian society, or maybe the Americans told them not to do it. I am sure we will find out in time...

  13. 6 minutes ago, Battlefront.com said:

    Excellent.  And I agree with Special Kherson Cat's summary about the look of this new drone.  It does resemble an aircraft rather than a traditional long range drone.  Certainly is BIG, which it would need to be to go that far with a significant explosives payload.

    The damage at the factory looks extensive.  That should disrupt production for quite some time, I should think.  I don't remember the last time I saw anybody guessing at how Russia produces these (i.e. how many primary assembly factories, sub contractors, etc.)

    Steve

    I'm not sure actually, I don't think production of those things requires much sophisticated equipment so I imagine production could begin again fairly soon (6 weeks?) unfortunately. But as a cheap demonstration it is still a valuable strike.

  14. 8 hours ago, sfhand said:

    And here, no evidence of a good faith discussion to be found. Start out assuming the worst possible motive and ATTACK!!! And I am a kid? How old are you? I'm betting I am older, and better looking to boot.

    Really, have a great day!

     

    I am going to try one more time here...

    Your posts come off sounding extremely confused. You make multiple statements without any logical connection between them and you seem to know they are controversial but you do not back them up with evidence. You keep citing Plato's cave but in a way that sounds like you are copying what someone else said without understanding it.

    Please offer simple and direct answers to people's questions. Imagine you are a professional writing a report for a client. You are not going to persuade anyone with long, poorly focused posts with no evidence. Because my finger is hovering over the ignore button and you only have yourself to blame. 

  15. 2 hours ago, sfhand said:

    Steve,

    What?

    So, "How do you know what you know?" is now "rather tired one sided "truth is only what I want it to be" filtering of facts into neat, convenient, self defined buckets of right and wrong." ???

    I guess you feel that way about Plato's cave allegory too... Good luck with that.

    The essence of a good con is telling people what they want to hear, at least from my experience on both sides of the equation. Ignore it at your own peril.

    Objecting to a government (any government, not just "mine") lying its people into war is "self defined buckets of right and wrong"? So, noble governmental lying then...

    Do you endorse all governmental lying or just the lying that confirms your biases? As a thought experiment, without moralizing, how do you feel about the Untreated Syphilis Study at Tuskegee?

    Or maybe you don't have any biases and have left the rest of us in Plato's cave?

    Yeah, I could have been more direct and left it to "How do you know what you know?" disregarding some of our recent history but that was my choice and I stand by it as relevant to the question because "Those who forget the past are condemned to repeat it" used to be considered wisdom. I guess it is now considered personal glorification through moralizing in some circles.

    This entire "war" has been presented through moral lenses, name one war that hasn't been. So I understand why you seemingly assign that position of morality to me. While, just like everyone but narcissists and psychopaths, I have a sense of morality, highlighting that was not the purpose of the post. So many hold their beliefs with such certainty, unwarranted certainty IMHO, without ever asking "how do I know this to be true". Which brings us back to Plato's cave.

    I don't object to you being stuck in Plato's cave with the rest of us. Of course you could claim you are no longer in the cave, but one can never be certain due to the nature of the cave. Maybe next time stop at "I have no idea what this is all about".

    As for the those being overtly hostile and rude, whatever makes them happy, I don't care... they define themselves not me. Rock on!!!

    As always, I hope everyone is having a great day.

    Sorry but can you explain in less than one paragraph what point or question you are trying to make here? I can't understand any of your posts. 

  16. 26 minutes ago, sfhand said:

    My plan is to have this be my only post in this thread... I've known about the thread from day one. I really only have one question about the whole thing.

    How can anyone know the truth of the matter?

    Yeah, when we invaded Iraq because of WMD's I was one of the ones questioning the decision. I watched in disbelief Colin Powell's address to the UN, the one with the crudely made computer generations of Iraq's supposed mobile WMD labs. Not satellite photos... crudely made computer representations - the lack of no photos was a big tell. I also read all of Hans Blix's report about there being no proof of WMD's and his willingness to keep investigating.

    Why was I so skeptical of the US government? I missed the Vietnam draft by 2 years. The Pentagon papers clearly showed those "in command" were lying through their teeth about the state of things. For me, this type of government mendacity erodes trust. Fast forward to Iraq and my saying to a friend during a work break meal as we watched the opening salvo Shock and Awe bombing on TV "I can't believe anyone believes the reasons for this after having gone through Vietnam". My friend's response "Obviously you don't know anyone who lives in New York" (guess where he was from). It was a very enlightening moment about the human condition and yet not enlightening at all about the justifications for the war.

    Then there's Russia-gate. You all know it has been thoroughly debunked right? In a court of law no less. See the Durham report. The whole "thing" was plotted by the Clinton campaign. There is also the Inspector General's report (Horowitz) about the FBI, and its head honchos, losing its/their way. When these truths were exposed one NYT reporter commented about the Clinton campaign liars thusly "...they lied and with sanctimony...".

    We were told the Hunter Biden laptop was Russian disinformation... Trump (who I will never vote for) was called out in a debate with Biden for promoting Russian disinformation by the mainstream media moderator because he mentioned the laptop. The moderator's reasoning: 50 former high ranking intelligence operatives said the laptop bore all the classic hallmarks of a Russian disinformation campaign.

    Have you ever wondered why Paul Manafort was tried and convicted for FARA violations while Hunter Biden is given a free pass? Or the fact that Peter Navarro was sentenced to prison for ignoring a congressional subpoena (yanked off an airplane and handcuffed) but Hunter faces no repercussions?

    So, we've got the CIA and the FBI running covert ops against the American public in order for form public opinion in their favor. Apparently there is a healthy appetite for wolf attacks these days because no one ever seems to ignore or tire of the boy calling wolf in real life. At this point Regan definitely got it backwards: verify before trusting. 

    The essence of a good con is telling the mark what they want to hear. No con can succeed without it.

    With this, I am out. I don't expect anyone in this thread to agree with anything I've added to this conversation and I am very much okay with it. I did want to voice my thoughts on the fundamental nature of matter. I hope you all are having a great day/night and enjoying life one day at a time.

     

    Consider that the USA is not the only country in the world. No matter how little you trust your own government how about the governments of most of Europe? 

    Even the French and Germans (Evan neutral Switzerland!!), who were very critical of the war in Iraq are fully onboard supporting Ukraine, supplying more aid per capita than the USA. 

    That suggests that the war is real and Ukraine is a partner who can be worked with. Remember the Dutch and Germans complaining about corruption during the eurozone crisis? Not so much with Ukraine (although realistically it does exist)

  17. relevant to the discussion about bunkers. These are probably a good tradeoff between cost and effectiveness - no wonder they are the ones getting shown off on camera!

    You can always dig deeper or use stronger designs (like those bunkers on the beaches of Normandy, or the Maginot line), but at some point you hit diminishing returns. Note that I am not a military engineer so my opinion on where that point is means nothing!

     

  18. 2 minutes ago, LongLeftFlank said:

    Well thinking generically in CM terms, the Ukes were hiding their strongpoints in the shattered ruins of whatever settlement (dachas, factories, etc.); that's been a classic underdog move for centuries (La Haye Sainte? Camarrone?). So the Russians had to level those with saturation bombardments using the heavy stuff.  Much the same in Bahmut.

    But those positions could also be (slowly and bloodily) outflanked, and their LOCs choked off, via the surrounding countryside, where only treelines and the occasional balka provide any kind of concealment and holes in the ground are the defensive cover, with whatever roofing is available.

    What about one of these:

    https://www.oxfordplastics.com/en-gb/products/road-plates-and-trench-covers?creative=691002070264&keyword=road plate&matchtype=p&network=g&device=m&gad_source=1&gclid=CjwKCAjwte-vBhBFEiwAQSv_xe3vbGdg50Rqi9Uihv0Sm1aYi4058J_7THowlj6MwRzeDoB-LTA_YxoCUbUQAvD_BwE

    It certainly won't stop a bullet (bullets are really good at penetrating stuff!) but will support enough soil to do so and is super quick to install. 

    But it would remain a niche use case since wood is cheaper and less flammable...

  19. 4 minutes ago, Kinophile said:

    I'm not sure about this - FPVs are certainly doing a lot of damage, but it was artillery & glide bombs that were the drivers for UKR to get out of Avdiivka. Shelling still happens constantly and a bunker that can resist shelling can resist an FPV. The entrance is the weakpoint, which could be countered by layer physical and EW aspects - eg, a right angle in the entrance hallway, some very short range but powerful jammer at the entrance and decent door?

    Tbh a plastic curtain like they use in industrial fridges would stop an FPV better than EW! Combine that with a right angled corner like you said and you will be pretty safe. 

     

  20. 35 minutes ago, LongLeftFlank said:

    But all this cement and steel requires heavy vehicles to move up (mud, anyone?), even if it's modular enough that ordinary grunts can assemble it without pioneers.

    I'm talking about stuff you can throw on your ordinary supply 4x4s along with camo and wev, and 'install' into a frontline area overnight, (hopefully) before the enemy drones can zero you. Rather than installing your Siegfried line stuff 25km+ back and ceding the terrain in front (hell, do that too).

    Will glorified Jersey barriers shrug off 122/152mm? Hell no. But it appears that's *not* what's mostly killing the Ukie grunts at this moment.

    ...As to flammable, I'd much rather put out a fire on my crappy lego bricks than be picking SPV frag/flechettes out of my skin and eyes. That's the threat that matters now, urgently.

    TBH, I believe the WaPo (did I really just say that lol) when they report on Ukrainian villages devoid of menfolk. Bluntly, Putin can shovel more meat into the line (willing or unwilling), so *anything* that lessens that blood flow, even if Ivan/China promptly copies it, is critical path on this phase of the war, to my mind.

    Ok so if we are trying to build bunkers under active fire from the enemy that does change the equation somewhat. But how bad is it? If you can't even bring in an excavator then it really limits your options and while throwing money at engineering problems often solves them (Kevlar sandbags?) I am not sure Ukraine has that kind of budget! 

    If I was in that situation I would be looking to pack something like this, or this on my truck and use it to support a lot of soil as overhead cover in a hand-dug trench. But it won't be nearly as strong as a concrete bunker since a near miss will collapse the walls more easily and a direct hit is game over even for a smaller round. 

  21. 46 minutes ago, Kinophile said:

    Are they done in panels, or complete sections? I've seen videos of formed concrete being placed into deep construction trenches - they landed onto concrete slab floors but the sides and roof were all one piece, with thickened wall corners and ceiling joints. 

    I've seen a lot of different designs tbh. The panalised system looks better from my armchair thousands of miles away but local supply chain issues may make other designs better in some cases. On the other hand, I have read reports that in many cases local commanders are just doing what they think is best, with limited engineering expertise to draw on so some designs may be wasteful of resources or just not very good. 

     

  22. 42 minutes ago, Kinophile said:

    Why bother with 3d printing? Its not faster for plastics than just stamping out forms. Would it not be easier to just create a mold (costly, sorta slow) and then just stamp out standerized bunker shells using heavy duty plastic mixed with kevlar? Once you get a floor line going it could complete hundreds in a day, using that one mold. 

    These could form the basic interiors and act as the internal formers for rebar concrete poured over them in-situ. A further liner inside to catch shrapnel/flakes from impacts would help. 

    3D printing has certain applications but its hard to beat the 10,000 year old concept of simple molds for just rapid, fast production using basic materials. Way less moving parts, for one!

    3D printed ballistic materials could offer significant breakthoughs - but I suspect we're quite a while away from beating the layering system of kevlar on cost & time.

    Remember plastic is very flammable so not good in combat - you would need a different material. Buildings are BIG and use a lot of material, so 3d printing is not going to beat mass production economically except for some quite specialised use cases. (This is a big subject that I have studied but I don't want to go OT)

    I am no expert on Kevlar but in construction carbon fibre is sometimes used - the downsides are that 1) steel offers most of the performance and a fraction of the price and 2) it burns. It ends up used in very specialised cases only. 

    The other reason why steel is almost always going to be best in "dynamic situations" is that it fails very gracefully by bending rather than snapping. Modern steels (even low grade construction steel) are really good and really cheap so very difficult to beat, especially if they are surrounded by concrete for fire protection and extra mass. 

    Basically the "best" bunker for mass production is likely what we have already seen - factory made reinforced concrete panels, welded together on site then covered in soil. Cheap, quick to assemble and robust (at least for a few years before they start to rust due to sloppy construction)

  23. 8 hours ago, LongLeftFlank said:

    (&*^%!! editor wiped out my post)

    Over on the defensive side of the mass production macroequation, check this whacky stuff out.

    https://ktla.com/business/press-releases/ein-presswire/695626991/micobs-3d-printed-bunkers-shine-at-bharat-shakti/

    Indian-Army-3D-printed-bunkers-1000x540.

    20461492-micob-s-3d-printed-bunker-demo-

    And sure, you'd want this stuff underground wherever possible. But sometimes it won't be possible, in which case I might take a pillbox, or even a glorified pot lid, over what that Ukie commander called a 'bald hole'.

    Note that one high volume manufacturing sector where the West (EU and USA) have NOT yet totally given away the store is higher end polymers and petrochemicals. So in contrast to my gloomy prior post, this could be a good place to catch up, innovating prefab substitutes to match China's knockoff/assembly behemoth.

    @dan/california, one good reason to accelerate the carbon transition may well be that humanity finds much higher value things to do with hydrocarbons than burning them (yeah, microplastics, but we're doomed any which way)

     

    https://www.archdaily.com/1014542/worlds-first-ever-3d-printed-mosque-opens-in-jeddah-saudi-arabia

    4265186-1035201719.jpg?itok=V1J_DWRT

    The links are broken for me but I am very skeptical about building  bunkers with 3d printing - and I say this as someone who designs structures, sometimes against explosions. If plastics are involved multiply that by 10. 

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