another version of an older post

I've posted on this specific thought here before, this is just me record-keeping a version I wrote up last night in reply to another comment on Reddit's 3D printing forum.

At time of reposting here, no replies, one upvote.

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This comes up every so often and I think about it a lot and here's the thing, and I don't see how I'm wrong, which doesn't mean I'm not:

PLA is a carbon sink.

Stored properly, PLA is a medium-term (centuries long) carbon store.

Everybody talks about PLA being compostable but only under specific conditions and people study ways to make that happen faster (which always involves making more methane, which isn't better) and how in a landfill it lasts hundreds to thousands of years, like any other plastic and so on.

And with most other plastics, that's not good because of the microplastics issue and bio-toxicity and all that, and all those are good and important issues, but PLA is literally used in medical applications because it biodegrades in animals pretty well and relatively quickly, meaning it doesn't bio-accumulate like other plastics do.

So the more I think about it the more I'm I think we don't want it to break down. If anything, we want to stack it in bricks in abandoned salt mines so it last 10,000 years because unlike any fossil-fuel plastic the carbon in PLA comes from the plants from which its made, and all of the carbon in plants - literally all of it..

...comes out of the air.

That's how plants work. That's how they build plant fibres. Nitrogen comes out of the soil, carbon comes out of the air. The majority of the molecular weight of PLA is carbon from plants. (50.4% I think? From memory, not including additives, etc. Just the PLA.)

And every gram of carbon in PLA represents 3.67g of carbon dioxide removed from the air by plants. (Roughly speaking. Typical carbon atomic weight 12, typical oxygen atomic weight 16, CO2 = 12+16+16 = 44, 44/12=3.67.)

So given that, every kilogram of pure PLA is contains 504g of carbon that doesn't just represent but literally is 1.83kg of carbon dioxide already extracted from the atmosphere.

As far as I can tell, if it were made in a carbon-neutral fashion, it would be carbon-negative.

At least, for the medium term. Between hundreds of and a thousand years.

Now obviously, it's not carbon-neutral otherwise, I mean, I have no idea how much oil is used hauling it around, how much carbon gets released in production, how much is released into the atmosphere via electricity to run our printers - we're all hydro here but that's rare and electricity is kinda fungible anyway - and so on.

But there's nothing unique about PLA in that. That part's all true also for wood.

I've asked other people I know what part of this is wrong and nobody's been able to tell me where I'm wrong, and I've done some - I emphasize some - literature search on waste PLA and what I've seen all focuses on the same sorts of things focused on in other plastics, which is to say, how to make it break down faster/better. Treating it for faster/easier composting, all that sort of thing.

And I keep going back to my botany classes and learning about how plants make cellulose and other plant fibres and were those elements come from and I keep thinking...

...what if we don't want to?

1d 7h 49m 51s

My longest-run print so far, 1 day, 7 hours, 49 minutes, 51 seconds. Basically one and a third days. It's nothing special, just an organiser I made to fit into a specific spot on the wall in my workspace of specific size, but I need that, so yay, it worked.


Ironically, it's with the most troublesome, annoying filament I have. (eSun matte ultra black.) I love how this filament looks the... one time in five times or so it actually prints. Even then it will lift off the bed in some corners.

(Literally the only 100% flawless print I've ever had with it - no flecking, no corner lifts, no separations - was the temperature tower I printed when I got it. Absolutely beautiful. Everything after that has been a nightmare. No other filament I've worked with has behaved even fractionally this badly.)

Version one of this was the first object I managed to print without bizarre spiky flecks sticking out of flat surfaces. I posted about that a while ago, the best solution I've found is "print objects with flat sides rotated 45 degrees."

Anyway, with the little bit I have left I'm going to test my 45° theory with an object that recreates the fleck bullshit 100% of the time, and also try my "maybe a raft with supports going up to the intended object hovering in space will work" theory at the same time, since I don't have a lot left of it anyway.

florida and maths texts

We don't know what the Florida @GOP in meant by rejecting maths textbooks for "critical race theory" (clearly a lie), but it likely has to do with the decades-long fundamentalist hatred for teaching how to think critically and analytically.

This would be in alignment with decades of fundamentalist attacks on anything that teaches children how to think, vs. teaching children what to think.

Like everything else, this is related to religious culture, and specifically, the fundamentalist culture that took over the Republican Party.

Fundamentalists of all sorts prioritize received knowledge, passed down from older sources, preferably god. The Bible, as they read it.

Sure, you can pick up technology maybe, but for what matters? God's Word or GTFO.

(That "God's Word" means their word goes without saying.)

Empirical knowledge - the idea that we can observe the world and make better decisions based on what we learn - falls by contrast somewhere between inferior and evil, if it contradicts what they've decided God Said.

Thinking critically is empirical thinking. That makes it bad.

Fascists think the same way. You've seen fascist "Reject modernity, embrace tradition" memes? That's just how they phrase it.

That's why they're so often found flocking together, and so easily align with each other.

God is Authority is Power is Good. Doing what God|Authority|Power says is right thinking. Everything else is somewhere flavour of the enemy, a.k.a. Satan.

So, teaching children to think critically - to engage with problems and solve them without deferring to received knowledge (God's Word / Authority's word / their beliefs) - is teaching children how to be evil.

Therefore critical thinking/analysis is evil, and must be expunged.

That's the level of difference we're dealing with here.

They used to say outright that things went wrong with the Renaissance, that that's when Man turned from God and where things started to go wrong.

That played badly, so they shut up about it.

But they still believe it.

If they have their way, so will everyone, Because God, or them, as god's spiritual warriors on Earth. (As they used to say.)

So to come back around:

We don't know, but that's likely what DeSantis is doing. Who he's making happy and why.

Education be damned, just learn to obey.

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(original version on twitter)