Welcome to Keen Software House Forums! Log in or Sign up to interact with the KSH community.
  1. You are currently browsing our forum as a guest. Create your own forum account to access all forum functionality.

What to do with Extra Gravel?

Discussion in 'General' started by ObjectZero, Mar 4, 2019.

Thread Status:
This last post in this thread was made more than 31 days old.
  1. Stardriver907 Senior Engineer

    Messages:
    2,918
    Well, concrete hulled ships are not unheard of. I believe all modern aircraft carriers have several feet of concrete behind the steel. Concrete as a hull material for spacecraft is still under consideration by designers of space habitats.

    In SE, "weight penalty" is something that gets mentioned by people that want advantages without disadvantages. Like energy shields. Concrete, especially concrete formulated for the task, would make an excellent hull material for spacecraft meant for battle. Probably not a good idea for a fighter, which needs to be fast and nimble, but battleships and carriers are neither and should be designed to take a pounding because running is not an option. Given the availability of stone as opposed to iron, repairs could be accomplished sooner.

    I would imagine an SE concrete hull block would weigh similar to a blast door block.
     
  2. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    The determination of block density in SE has always been strange to me. Reinforced concrete, with a nominal density of about 150 lb/ft³ (2.40 g/cc), is significantly less dense than steel of about 490 lb/ft³ (7.85 g/cc). Since we really don't know about the inner structure of the various blocks used in SE, mass of each seems somewhat arbitrary to me.

    I've never heard of concrete being used behind armor plate in the hull of any aircraft carrier or other serious fighting ship. Its effectiveness as armor would only be relevant to shaped-charge weapons where the concrete would serve as the "soft" layer thereby diffusing the energy wave from the detonation. Kinetic energy weapons, however, would benefit from the relatively soft concrete, so I just can't see why it would be used. But, that said, I'm not a ship designer. Maybe things have changed in recent years and everything I've said is irrelevant.
     
  3. Stardriver907 Senior Engineer

    Messages:
    2,918
    I did say concrete "especially formulated for the task", as in not quite the same concrete used for road construction ;)

    I did mention the concrete was behind the steel armor?
     
  4. FoolishOwl Junior Engineer

    Messages:
    507
    We do get to see their inner structure as we weld them or grind them. Armor blocks are hollow, with flat sheets of metal on a framework. The density of armor blocks is very low -- when I checked the numbers, light armor is less dense than empty aluminum soda cans. (In gravity, you'd punch through light armor by stepping on it.)
     
    • Agree Agree x 1
  5. Stardriver907 Senior Engineer

    Messages:
    2,918
    Yeah. Truth is that of all the things you could make spacecraft out of by 2077, steel would probably be the least likely just above wood. I only say that because I don't know what hard vacuum and radiation does to wood, but I bet it would even be chosen over steel.
     
    • Disagree Disagree x 1
  6. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    Look at today's spaceflight systems: essentially all aluminum because of weight considerations. Steel is used sparingly, with titanium often used for critical, load-bearing components. Yeah, steel would be a last choice, I think. I can't speak to the future's metallurgical advances, but probably a lot more with carbon (or other) nanotubes and the like.
     
  7. Cyborg_Leopard Trainee Engineer

    Messages:
    26
    Fill a cargo container with it. Fly 1.1km above enemy base. Grind cargo container.
     
  8. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    Remember the days when you could fill a large cargo container with stone (or even a small one), attach a warhead, and detonate that sucker near a base or ship and watch the massive amount of stone that was ejected annihilate everything nearby? Now that's what I'm talking about!
     
  9. ObjectZero Apprentice Engineer

    Messages:
    361
    Yup I remember doing that, it was fun to watch. The early stone gravity cannons where also fun. A bit of a task to make but once you got one running it was not something you wanted to hit by.
     
  10. mojomann71 Senior Engineer

    Messages:
    1,661
  11. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    An interesting article, but it's not without some errors. But, then again, I'm just a mechanical engineer and my knowledge of materials, especially steels, is somewhat less than a materials engineer.
     
  12. FoolishOwl Junior Engineer

    Messages:
    507
    I tried constructing a bomber, ejecting gravel from connectors, as a means to beat the pirate base in the survival tutorial. The gravel simply bounced off without doing any damage.
     
    • Funny Funny x 1
  13. Stardriver907 Senior Engineer

    Messages:
    2,918
    There are a lot of good reasons to use steel on Earth that don't exist in space. Steel is useful on Earth because of the weight it can bear. That's why we use it to make buildings and bridges, and prefer it to concrete for those applications. In space you worry more about structural integrity, and if we are talking about spacecraft that is expected to move you also worry about weight.

    Weight is why aircraft were first made out of wood and then we went straight to aluminum and now we are using composite materials. You can get similar strength with considerably less weight. If your spacecraft was designed for battle it's still more likely that the dominant building material would be some sort of composite or alloy.

    I'm not saying that no steel would be used. I'm only saying that there's so many more appropriate materials out there that steel winds up pretty close to the bottom of the list.
     
  14. FoolishOwl Junior Engineer

    Messages:
    507
    Building aircraft out of steel may not be optimal, but it's certainly a viable option. Consider the MiG-25:
     
  15. Oskar1101 Apprentice Engineer

    Messages:
    226
    Also SpaceX starship and super heavy booster will use stainless steel as main hull material.
     
  16. Stardriver907 Senior Engineer

    Messages:
    2,918
    Yeah. Soviet Russia did not have all the options the rest of us had. Plus, Soviet aircraft had to be... durable. MiGs could land in a farmer's field. Try that with an F-16.

    Again, when we are talking about spacecraft in 2077, steel would be at the bottom of the list of available, viable building materials. Only in the SE world it becomes the material of choice.
    --- Automerge ---
    I had to check to be sure but, technically, neither of those are spacecraft. If it is built to withstand the rigors of gravity and has to be aerodynamic, it is not a spacecraft. The International Space Station will disintegrate it it gets any closer to Earth than it is now. It's a spacecraft and It ain't made out of steel ;)

    Although, that's mostly because that made it easier to get the parts up there.

    Still, I'd bet composites and not steel as hull material in 2077.
     
  17. mojomann71 Senior Engineer

    Messages:
    1,661
    @Stardriver907 Fun fact the F-16 is the only Air Force fighter made with aluminum alloy, all others including the newer f-24's are all made with titanium. The F-16's were massed produced in the Vietnam era, so it was low cost faster production. :)

    (No way is this comment meant as a troll or argument, just for basic knowledge and info.) :)

    P.S.:

    <--US Air Force Veteran
     
    • Informative Informative x 1
    • Friendly Friendly x 1
  18. mhalpern Senior Engineer

    Messages:
    2,119
    You say that but at cryogenic temps, cold formed stainless is stronger than carbon fiber...
     
  19. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    The only steels utilized for cryogenic applications are Type 304 or 316 austenitic stainless steel; martensitic and ferritic stainless steels just don't cut it at ultra-low temperatures because they exhibit a ductile-to-brittle transition temperature at much higher temperature levels. Most often Type 304L and 316L stainless steel are used because the low carbon content improves weldability and reduces stress-corrosion cracking problems. My particular work as a mechanical engineer has me specifying those specific alloys on a regular basis, although for nuclear and not for cryogenic applications. Austenitic stainless steel is not strong. It just isn't. Even standard, dirt-ball structural steel (ASTM A36) that's used on most bridges and buildings has a higher yield strength. What austenitic stainless steel does have, however, is a very low ductile-to-brittle transition temperature, which means it's not susceptible to brittle fracture, and very high ductility; you can bend it over on itself and not crack it, even at ultra-low temperatures. That stuff is "tough", where toughness is a measure of the alloy's capability to absorb impact energy (most often demonstrated by Charpy or Izod impact testing).

    What I know about carbon fiber, especially with regard to cold temperature viability, is extremely limited. I do know it's strong stuff relative to its weight, but so is spider silk. So, in my opinion, unless you're a knowledgeable materials engineer, especially with regard to those two specific materials, I don't think you're qualified to make such a blanket assertion.
     
    • Informative Informative x 2
  20. mhalpern Senior Engineer

    Messages:
    2,119
    Well you better tell that to SpaceX
     
  21. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    I. Know. What. I. Know.

    SpaceX is building their craft using a very thin, cold-formed shell (skin) of austenitic stainless steel. The only way to harden austenitic stainless steel is to work-harden it, i.e., cold-roll it. "Cold-rolling" means forming the material ("rolling" for sheet material) at a temperature below the material's recrystallization temperature. Cooling the material way down and then rolling it work-hardens it much more extensively than doing it at room temperature. How does cold-rolling make the material harder and, correspondingly, stronger? The rolling process upsets the crystalline boundaries, and these misalignments significantly affect the material's strength. Now the downside, which I'm sure they're discovering already: with all those locked-in stresses from cold-forming, the moment you try to weld it the sheet will "potato-chip" so severely that they may never be able to get an aerodynamically smooth surface for efficient flight. Austenitic stainless steels are notorious for warping all over the place when welded. They just are. Good luck, SpaceX dudes. Good luck.

    (P.S. That's why we spec-out annealed hot-rolled sheet materials for the stuff we fabricate; in that form, locked-in rolling stresses are significantly reduced and warpage is correspondingly minimized.)
     
    Last edited: Mar 30, 2019
    • Like Like x 1
  22. Thrak Junior Engineer

    Messages:
    535
  23. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    Can I have some, too?
     
  24. Thermonuklear Junior Engineer

    Messages:
    611
    How did we get from gravel to A36!? :D hey, it's good forging stock and you can ask your steelyard if they'd like to sell you some offcuts...
    EDIT: Spiff's posts confused me, I thought this was iforgeiron.com :D
     
  25. Spaceman Spiff Senior Engineer

    Messages:
    1,355
    It's the nature of the beast, i.e., entropy at its finest.
     
  26. Stardriver907 Senior Engineer

    Messages:
    2,918
    Question was what to do with gravel, and I suggested concrete (which needs gravel as an aggregate) would be a good substitute for steel as a structural material for spacecraft. I also pointed out that steel would be an unlikely structural material in 2077 given the number of alternatives available today. I'm frankly puzzled as to why the primary building material in SE is steel and not aluminum, especially given how recyclable aluminum is. I mean, if the game took place in the 1800's I could see where everything would be steel. By 2077? Synthetic spider silk is more likely than steel.
     
    • Like Like x 2
    • Agree Agree x 1
  27. Soup Toaster Apprentice Engineer

    Messages:
    184
    Because the majority of us players are relative lunk-heads who don't know any better and--to be brutally honest--don't really care. Steel STRONG. Aluminum weak! Aluminum for beer can crush on forehead! AAaaarrgh!

    I mean, it is a game where we use a magic blow torch to make space ships sooooo........
     
    • Agree Agree x 1
  28. Einharjar Junior Engineer

    Messages:
    518
    I agree with @Stardriver907 here, I don't know why Steel is the go to flight material when light weight aluminum should be offered, but then again it doesn't really matter as the Armor Blocks are literally just stand ins.
    I would like to see Aluminum be a rare element that you can use to make more advanced armor blocks with, a later "tier" variant specifically for light weight crafts but I highly doubt Keen will do this as they're constantly worried about block count in the G-menu.

    As for the gravel, like many others I use concrete mods to act as a gravel/refuse sink and I use it to exclusively build bases with and yes, mods do make them resistant to thruster damage which makes them great station and base landing pads.

    The problem I have with these mods in survival mode is that they're extremely tedious to use. Basic light armor blocks require far less components and are way less massive, so you can carry a LOT of steel plate around and weld at least a dozen or so light armor blocks up to get your shelter doing, lay a foundation, work pad, whatever.
    The concrete blocks are so massive, taking SO MUCH material that it's literally a chore building one block, much less an entire base walled by them. It's only practical to use the concrete in construction once you've got an effective welder vehicle of sometime that can far more easily lug the loads around.

    As a special note, @Spaceman Spiff mentioned the calculations for typical density of concrete and how SE handles the mass calculations of it's block to be odd. I'll add that I think the mod I use is actually spot on accurate in terms of the mass calculation (regarding the gravel mass, the metal grids are just overkill) as they're using typical reinforce concrete mass per a 2.5m cubed block. In SE, the steel based armor blocks are unassumingly hollow, hence why they only take 30 odd pieces of steel plate (for a light armor block). The heavy armor block is the one armor type that I think Keen calculates to being nearly, at full volume, packed with steel. It uses WAAAAAAY more material than the light armor variant does. This isn't to say that SEs system is actually truly accurate as it's pretty close? But... has massive issues. Building replica fighters from IRL in SEs is the equivalent of building lead bricks that fly since things like conveyors are literally block holes of mass for no damned reason... I mean come on Keen, the MiG 25 was mostly steel because the Russians couldn't use titanium as effectively as the US and the thing could still fly well enough to cruise at Mach 2.8 - an equivalent craft in SE (proportion wise) can weight ten times more in some cases, without mods. It's hilarious.

    ANYWAYS, back on track -
    For me, I wouldn't make concrete so massive as I do think for the mod I'm using specifically, it uses heavy metal grids as one of the component requirements and it uses a fair share of them per 1x1x1 block. The 5x5x1 is just INSANE to do on your own or without mechanic assistance. I'd prefer the mod I used to use simple steel tubing instead to act as the " steel rebar". To balance the block type, I'd simply make the concrete blocks NOT transfer power. They're literally just armor and structure only. This alone should reduce their effectiveness in most vehicle applications as one of the main advantages to how current armor blocks works is that they all transfer power; making "redundancy" go over power on making sure you never lose a "connection" to a valued system on your ship or rover. The mod I use DOES transmit power and that to me is problem. It basically turns it into a super heavy armor block that yes, while heavy? It's nothing that a good Epstein Drive mod can't move...

    To be fair though, in my survival runs where I do get to use concrete (after literally making vehicles purpose built for hauling the materials), the concrete mods DO provide an amazing Gravel sink. I usually run out of gravel just building good sized vehicle pads. When you're still mining with just your trusty hand drill, the gravel runs thin pretty quickly, and this is true even on games where I've had it set at 10X Inventory storage. On games like my current experimental scenario test where everything is on realistic, that gravel goes WAY FASTER with the concrete usage and the gravel also wastes more space far faster; encouraging me to use it. If it wasn't so damned inconvenient to build because of the heavy steel grids I'd not complain so much but those steel grids just make it such a damned chore.

    As for my Keen wishlist, I really do wish they'd just get off their bums and realize how awesome it would be to just let us use the basic armor block types in concrete form. Have it not transfer power and have it use gravel and steel tubing as a base so that the starting Survival Kit could produce it as a starting tier shelter material. I want to see the "Temperature" get far harder. I want to see my Engineer get too hot and get too cold way more frequently, encouraging the use of the shelters. Making concrete easily usable from the start of the game onward is key. The current mods have concrete feeling like a more advanced material when it should not be. The first thing I want to do when I find a good spot to settle down is break down some stone into future concrete and begin building my space age adobe, meticulously only using the steel light armor to only trace power connections to power using blocks.

    This is sort've misleading as I don't think you specified how much material per aircraft is actually used. The statement "Fun fact the F-16 is the only Air Force fighter made with aluminum alloy, all others including the newer f-24's are all made with titanium" comes across as "we build entire fighters out of nothing but titanium!". That's one insanely expensive fighter and as such would have out done the SR-71 which itself was not made purely out of titanium. All current aircraft (aside from ones you shouldn't know about *COUGH COUGH*) are using Aluminum SOME WHERE and in all cases, are MAJORITY Aluminum. If you were a crew-chief in the USAF, I do believe when you train and certify in BDR, you'll also get certified in Aluminum specifically since it's a far different alloy to weld and rivet than typical steel. I'm not saying you're wrong, just... maybe worded a bit misleading?

    To date, the SR-71 is the last thing we produced that used so much Titanium in ratio to it's full dry-weight. IIRC, the construction ratio was something around 80% of the air-frame, compare that to the MiG-25 which Russian could only afford to use 20% or less in it's airfame. That is a lot a' titanium and today's market, would be absurdly overpriced (but hell, I'd pay for it).

    Titanium is easier to manufacture here in the States due to better tech and infrastructure in comparison to say, Russia, but it's still expensive as shit and we still only use it for performance critical parts, such as leading edges, high stress/weight bearing bulkheads or the blades and stators in our engines. As an example, even the new F-35 still uses typical aerospace grade alloys of aluminum, even the flat rolled stuff (specifically from AMI. Don't worry, this is public knowledge). The CATOBAR and STOVL variants use more titanium for structural reinforcement than the standard A model for obvious reasons but it's only because it's practically required for the intended mission of those variants as we don't want a repeat of the F/A-18C issues where stress risers would show up after 2 to 3 years of carrier ops. Northrop (actually the defense budget, Northrop made bank but was punished for it) paid a pretty penny in the maintenance contracts for those aircraft with how frequently they'd be rotated out of service to get X-rayed and dye-penetrated for all the stress risers and cracks in the honeycomb structures. We already in hot water for how expensive the F-35 is, don't need a repeat of the Hornet biting us in the ass (Boeing can take that load, HAHA!!!).

    (source: I uh.. may or may not work for a specific defense contractor)
     
    • Informative Informative x 1
  29. mojomann71 Senior Engineer

    Messages:
    1,661
    @Einharjar *COUGH COUGH* My statement did not say they were made entirely of titanium. *COUGH COUGH* the F-16 isn't made purely out of aluminium. *COUGH COUGH* It was stated basic knowledge. I mean I could go into detail part by part and material by material, and come off as being a douche........*COUGH COUGH*

    :p
     
  30. Einharjar Junior Engineer

    Messages:
    518
    That's what I mean though. The statement I bolded is just kind'a worded odd. I know you don't mean it that way but it doesn't make a very clear distinction and can lead to being easily assumed.

    Literally sounds like (by accident) that the F-16 is the only US fighter made with aluminum :woot:. See what I mean? I'm not question knowledge here, just the statement being easily misread.
     
Thread Status:
This last post in this thread was made more than 31 days old.