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One thing I always look at in post-apocalyptic literature is how they treat transportation: notably, are people still driving cars and how long can they do so and under what conditions?

Entering our current oil crunch, I think it's obvious how fragile the ecosystem around cars are, but just letting the car sit unused and untreated for as little as a month can start to introduce\ problems. The idea that you can just pop into a car that's been abandoned for 3 years, pull the keys out from behind the visor, and start driving is unrealistic.

  • Best: The Postman. We're back to walking and riding horses.

  • Good: The Last of Us, Season 1. People walk or ride horses, when our heroes DO find a working truck, it is treated as the jackpot it is--and I think it even had a spare gas tank in the back to maximize distance traveled to harvest gasoline. Realistically, gas as a fuel for fires would be a valuable enough commodity that it would have been scavenged, but they need to do some traveling and high speed dragons are not available in this genre (Reign of Fire aside).

  • Worst: Jericho. Nuclear explosions in the US pretty much wreck everything and despite the town of Jericho being completely isolated, people just drive their pickup trucks around all seasons long without comment. Horses and bicycles are maddeningly present but rarely used. I think the show thought American audiences could accept a premise where the federal government collapses after multiple nuclear strikes, but not where people in Kansas got off oil dependency--that would be too out there.

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[–] gloktawasright@lemmy.world 30 points 1 day ago (2 children)

Something else that’s often ignored in these scenarios is that gasoline is not shelf stable for very long. Without refineries or biofuel, most gasoline would degrade within a year from what I understand.

Most realistic would be horses, bikes, maybe biodiesel converted cars or motorbikes and a biodiesel creation setup. I could also see electric vehicles with solar or constructed wind/water wheel power to charge batteries. But batteries of course degrade as well so that isn’t a long term solution unless you can make and repair batteries. Which is a stretch.

[–] schipelblorp@sh.itjust.works 16 points 1 day ago (3 children)

I think gasoline used to be more stable, but in 2007 the US gave in to the corn lobby and started adding corn ethanol to gasoline, which does limit shelf life. That's right, in the United States we take food and give it to our cars.

Motorbikes + biodiesel is probably as far as I´d be willing to go, but we're well back on the path to civilization at that point. You can kickstart a bike without a battery, too...

[–] gloktawasright@lemmy.world 14 points 1 day ago (2 children)

Looks like you’re right about ethanol affecting shelf life, but it goes from 3-6 months to around 12 months. So still an issue in longer term apocalypse worlds

https://universaltrades.co/blog/gasoline-shelf-life-guide-en/

Also, I don’t think setting up a small scale biodiesel plant would be out of the question for a large enough sect of sufficiently educated humans in an apocayse setting. But it’s definitely a step above something that a small homestead could reasonably expect to setup imo.

https://www.wikihow.com/Make-Bio-Diesel

[–] schipelblorp@sh.itjust.works 5 points 1 day ago (3 children)

Obtain good-quality oil. The easiest oils to use for biodiesel are neutral vegetable oils like canola, corn, and sunflower oil

I think this where the crunch would come in. Biodiesels are economically feasible because of factory farming, which have massive carbon inputs. Could a small community farm enough biodiesel to make the investment in that bushy tech tree worthwhile? I tend to doubt it.

[–] gloktawasright@lemmy.world 4 points 1 day ago (1 children)

Yeah I’m inclined to agree with you. More likely to me would be sourcing and preserving some of those oils so you have a more stable mid term fuel source, but eventually when that runs out you’d need to pivot to other options.

Something like use cars and motorbikes for 1-2 years, then convert to other fuels based on availability and knowhow for the next however many years, then back to horses.

[–] schipelblorp@sh.itjust.works 4 points 1 day ago (1 children)

Cool. You can be Transportation Secretary for Schipelblorpia Enclave.

[–] gloktawasright@lemmy.world 4 points 1 day ago

Lol. What an honor.

[–] CanadaPlus@lemmy.sdf.org 2 points 1 day ago* (last edited 1 day ago)

In terms of quantity, it depends on competition from food production, basically.

Modern fertilizer and pesticides allow you to get a much higher yield on the same land, and modern farming vehicles allow you to plant and harvest whatever oil crops without an army of labourers. If you had a ton of idle land, because all the urban people are dead, it reduces to the second problem.

Pressing/steeping the oil out of it is another challenge. Probably surmountable, although it's still going to cost a lot more than it does now.

[–] grue@lemmy.world 2 points 1 day ago (1 children)

of factory farming, which have massive carbon inputs

The fuel used to run the tractors can itself also be biodiesel.

[–] schipelblorp@sh.itjust.works 1 points 18 hours ago (1 children)

Absolutely! The question are is you want to have an agricultural system with such a fragile link in the chain. And modern factory farming isn't just "a tractor", which can certainly help small scale operations. I can see a tractor being an adjunct, but probably supporting a large group of farmers, who, at any rate, probably need to keep busy anyway.

[–] grue@lemmy.world 1 points 17 hours ago (1 children)

How is a thing you can do yourself in a closed loop "fragile?"

[–] schipelblorp@sh.itjust.works 1 points 17 hours ago (1 children)

Because there are a lot of parts on the tractor that might need to be repaired and replaced. Even if you had access to everything you need, how many people are going to know how to do it?

And timing is critical in faring, so you'd have to get the tractor repaired quickly if anything goes wrong.

So if you lose one person or can't fix one part quickly enough, your entire agriculture system falls apart if its based around a tractor.

A system built around human labor or even animal labor is much more resilient.

[–] grue@lemmy.world 1 points 15 hours ago* (last edited 15 hours ago) (1 children)

We were talking about carbon inputs and biodiesel, not reliability. Growing biodiesel has no carbon inputs if the farm itself runs on biodiesel.

[–] schipelblorp@sh.itjust.works 1 points 15 hours ago

Just looking at the whole picture. Farms do not "run themselves on biodiesel," they put that biodiesel in machines.

[–] rain_enjoyer@sopuli.xyz 4 points 1 day ago (1 children)

but you wouldn't be able to get methanol you'd have to use ethanol, and also perhsps make your own sodium hydroxide or potassium hydroxide (wood ash + slaked lime) not saying it's impossible but it gets a notch harder

[–] gloktawasright@lemmy.world 2 points 1 day ago

For sure. And I’m not claiming to have all the answers or the best long term or sustainable processes. I think you could reasonably set up a still to make methanol:

https://www.sciencing.com/make-methanol-5396607/

Similarly for NaOH, though you’d need to source cacium hydroxide

https://theblogjournal.com/how-do-you-make-sodium-hydroxide-at-home/

I could see sourcing some of these more shelf stable components from places that apready had them, but as for what happens when those run out, yeah, you’re just going to have to find something else or find a way to make it yourself.

[–] vinceman@lemmy.blahaj.zone 2 points 1 day ago (1 children)

If you look into it, lead fuel also tended to last longer. Not saying 10 years, but for sure another year. Also premium still lasts longer than regular, obviously not talking e85 though.

[–] schipelblorp@sh.itjust.works 1 points 18 hours ago (1 children)

Where do you get leaded fuel in this day and age? Gas has been unleaded since I was a kid.

[–] vinceman@lemmy.blahaj.zone 1 points 14 hours ago (1 children)

Race gas. But my point was more so speaking to gas lasting in popular culture.

[–] schipelblorp@sh.itjust.works 1 points 14 hours ago* (last edited 12 hours ago) (1 children)

Ah, nice. Pinning location of race tracks along with homes of known survivalists to my map....

[–] vinceman@lemmy.blahaj.zone 2 points 13 hours ago

I'm just gonna build a raft and go shit in the air vents of all those NZ bunkers personally. Ignoring that I'm in one of the most land locked locations on earth for this fantasy lol

[–] rain_enjoyer@sopuli.xyz 3 points 1 day ago* (last edited 1 day ago) (2 children)

Not sure where you get diesel motorbikes, but ethanol is easily made gasoline replacement. And also propane while it lasts, because it doesn't go bad at all. Then when it's not around anymore, wood gas is an option

As long as you keep it well sealed, gasoline esp sold in summer should last some decent time, just like winter diesel (less wax to form precipitate). I think one of big problems would be bacterial degradation (yes there are bacteria that feed on hydrocarbons)

[–] gloktawasright@lemmy.world 2 points 1 day ago* (last edited 1 day ago) (1 children)

I was thinking of a situation where the people had enough skills and knowhow to make conversions of existing bikes.

https://www.motorcycles.news/en/biodiesel-harley-kubota-conversion/

In that situation, you might be better off converting to using propane or ethanol like you suggested depending on available resources and expertise.

Unfortunately, I don’t think you’re right about gasoline’s shelf life however. If stored properly AND stabilized it looks like around 3 years is the best you could hope for.

https://build-construct.com/practical-guide/gasoline-shelf-life-how-long-does-fuel-last-and-how-to-store-it-properly/

[–] schipelblorp@sh.itjust.works 2 points 1 day ago (2 children)

The conversion is a possibility, but mechanics also requires an eco-system of parts or at least machining. Let's say you're a machinist. How are you going to run your machines without electricity? With a generator, of course. But what if you need a part for that generator?

There's an ever-expanding web of dependencies...

And you can scavenge and modify, but rubber's another issue. It gets dry and brittle with time. Where are you going to get more rubber?

You can figure something out with enough time and effort, I guess, but that's time and effort likely spent elsewhere, especially if gas isn´t cheap. A lot about vehicles requires economy of scale and global supply chains.

[–] gloktawasright@lemmy.world 3 points 1 day ago (1 children)

For sure! Ideally you have enough redundancy in machining and power generation and such that you can sustain yourself for a while, but it’s highly likely that you end up needing a component you can’t replace or substitute that causes you to lose capability over time and eventually you backslide to something like American pioneer level tech plus a few things you can limp along with.

That said, with a water wheel and some basic hand tools along with a a lot of starting equipment, you might be able to maintain a few key machines for quite some time.

Having a working lathe and blacksmith shop with starting tools would get you pretty far for quite some time if you had enough people with some skills to use them.

But yeah, eventually you’re probably back on horses livestock power for the most part until you can build enough stability back up to start specializing and trading and such.

[–] schipelblorp@sh.itjust.works 2 points 1 day ago* (last edited 1 day ago)

Yes, surely a lot of what we would be doing is going backwards, to watermills and smithies; but I wonder what would be new, what little tricks and things we've learned that would be thoroughly modern.

Edit: I'll answer my own question: Photovoltaics last forever. You can rip 'em off abandoned homes pretty easily.

[–] CanadaPlus@lemmy.sdf.org 2 points 1 day ago* (last edited 1 day ago)

Solar electricity would still be an option. Lots of people will want electricity, so it's pricey, but if you're the only guy that can make essential machine parts you can probably afford it.

If you were a caveman starting over, a waterwheel has about the needed output. Heck, some of the first metal lathes might have run on those, historically.

Rubber might just be a wonder you'll have to do without, if you're somewhere temperate.

[–] schipelblorp@sh.itjust.works 2 points 1 day ago (1 children)

I did a search for a diesel bike and on a national bike sales data base and found nothing; you are more likely to find a horse.

The internet tells me gas can last conservatively up to 12 months, but ethanol no more than 3 months. Most post-apocalyptic narratives are built around travelling, and if people are getting around by locally-produced ethanol, you are doing more of post-post-apocalyptic story.

[–] MrOtingocni@lemmy.world 1 points 5 hours ago* (last edited 5 hours ago)

A diesel bike would be very impractical due to the nature of how diesel is combusted vs gasoline. It requires a much bigger engine block and compression. A much easier option is to just tweak a gas engine to run on pure ethanol. And that works particularly well for a small motor bike over a car.

[–] dismay3915@lemmy.world 1 points 1 day ago (1 children)

I think bikes are also not very good since they need maintenance and parts, and it will be very hard to find those and they won't be produced anymore.

[–] grue@lemmy.world 9 points 1 day ago (2 children)

Nah, bike parts last a long time and are relatively simple to fix or even make (as long as you're not talking about some dentist's $10k carbon road bike). My main (non-electric) bike is from the early '90s and is still on most of its original parts, except for stuff like tires, brake pads, and the chain.

Also, bikes have existed for 200 years, which means they predate things like, say, the assembly line. I'm pretty confident that even in a post-apocalyptic scenario you could scrape together enough of a supply line and basic tools to build them from salvaged raw materials.

[–] schipelblorp@sh.itjust.works 3 points 17 hours ago

I love this conversation of the Post Apocalyptic Bike Foundry, but gotta say that bike frames will be absolutely ABUNDANT and it would make no sense to manufacture them When most every basement and garage and department store has bikes in them; plenty to scavenge.

The part I'm curious about is tires. Rubber gets old and dry and cracks. What do you make tires out of of without rubber? Maybe leather bound to the wheel? And replace frequently?

Edit: Looks like you can recycle rubber, but not sure what equipment you need, but I'm sure it's going to smell awful.

[–] CanadaPlus@lemmy.sdf.org 3 points 1 day ago* (last edited 1 day ago) (1 children)

Lathe + drill + foundry to cast a big enough chunk for the lathe and drill. Rivets for putting together the frame. (And some power source to run your shop)

Maybe an endmill or even CNC machine, if you're feeling fancy, or welding for the frame (someone else might know what exact kind of welding you need).

[–] grue@lemmy.world 3 points 1 day ago (1 children)

Rivets for putting together the frame.

Nobody rivets together a bike frame. Frames are brazed, welded, or (in the case of carbon fiber, bamboo, or occasionally aluminum) glued. The only places I've ever seen rivets on a bike are on the chain, old-school leather saddles, and maybe to attach layers of stamped steel on really cheap brake calipers.

Maybe an endmill or even CNC machine

Or even just a set of hand files.

or welding for the frame (someone else might know what exact kind of welding you need).

More carefully-constructed bikes typically use TIG, and for aluminum you want an AC welder. But who's going to be making a titanium, aluminum, or even fancy steel (with Tange or Columbus double-butted tubes) bike in the apocalypse? Any welding process would work for steel, especially when you're building out of random scrap plumbing pipe or whatever.

Your most realistic options would be stick, MIG, or even just brazing with a propane torch. Or building your bike frame from bamboo lashed together with rope and glued with pine resin.

[–] CanadaPlus@lemmy.sdf.org 2 points 1 day ago* (last edited 1 day ago) (1 children)

The reason I brought up riveting is because you can do it with basic hand tools (and an open fire for hot riveting). If some kind of welding would work, yeah, do it the normal way. You aren't going to have propane, though, and insulating gasses might require some ingenuity.

If you can hand file a bearing that runs reasonably smooth, I'm impressed as hell. Definitely somebody can - the first lathe got made somehow - but it's definitely not me.

Wood might be an option, and bamboo seems like it would be a decent option. Once you're talking wooden sprockets and chains, I'm guessing your going to end up with a pedal wagon more than a bike, though, because it's going to be pretty heavy.

[–] grue@lemmy.world 3 points 1 day ago* (last edited 1 day ago) (1 children)

The reason I brought up riveting is because you can do it with basic hand tools. If some kind of welding would work, yeah, do it the normal way. You aren't going to have propane, though, and insulating gasses might require some ingenuity.

Nobody rivets a bike frame because it's made out of hollow tubes and rivets are designed to pinch flat things together. Rivets are just the wrong tool for the job.

Of the metal-melting joining methods, I guess brazing is probably the most low-tech. Maybe propane would be a problem and you'd have to use some other fuel instead (maybe wood gas?), but it's been a thing since 3000 BC so I'm sure an enterprising person could figure some solution out.

Alternatively, the flux coating on a stick welding rod is apparently made mostly of cellulose, which is less exotic than I expected.

If you can hand file a bearing that runs reasonably smooth, I'm impressed as hell. Definitely somebody can - the first lathe got made somehow - but it's definitely not me.

Behold, a lathe:

This stuff isn't as high-tech as you think.

But never mind that; depending on what scenario we're talking about it seems likely some machine tools would survive (e.g. in rural areas, maybe), so the trick would be to find one and get it running.

Once you're talking wooden sprockets and chains,

I am not. I'm talking about, say, salvaging sheet metal from abandoned cars and stamping chain links out of that. Nobody wants a wooden chain; if you're that hard-up, you'd probably be better off trying to go for a belt drive or shaft drive. Or hell, even a penny-farthing!

[–] CanadaPlus@lemmy.sdf.org 1 points 9 hours ago* (last edited 9 hours ago)

Nobody rivets a bike frame because it’s made out of hollow tubes and rivets are designed to pinch flat things together. Rivets are just the wrong tool for the job.

Good point. Like, it seems like another kind of beam would work, but you never see that. Maybe it's about aerodynamics?

[Pole lathe]

I'm definitely aware of the pole lathe, but you can't really do metal machining on it. For that, you'd need at least a Gingery lathe. Or, I'd assume so, since Gingery wasn't an idiot.

The first pole lathe would have had a freehand-made bearing - Gingery mentions the same thing about the first screw, as well. I made a post about the problem of bootstrapping bearings once, and there probably is an alternate way if you're mostly booksmart, but in any less complex society you have a fair amount of master handcrafters who can do crazy things.

But yeah, there's little machine shops in my rural area, at least. Toolmaking would probably be the bottleneck over the long term. And just things being designed to lock down if tampered with by anyone but the OEM - farm equipment is notorious for that.