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Hardened wood as a renewable alternative to steel and plastic

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Re: Hardened wood as a renewable alternative to steel and plastic

#271

Post by quixoticelixer- »

megameter wrote: post #193
KennyBlanken wrote: post #178

Earlier quoted context omitted.

That's an article about toilet paper usage, not building material. There's no petroleum toilet paper, by the way. Wood is biodegradable, renewable, and recyclable. It can be grown and harvested sustainably; I know because I used to work with a guy who made a living off surveying forestry for sustainable timber harvesting. It causes no environmental issues if left to rot, doesn't have to be disposed of in a particular…

Wood itself is sustainable, but in making a choice of building materials, we're also looking for total embedded energy cost and impact of the final product. Traditional buildings from a century ago relied on the harvest of old-growth wood with denser rings than the new sustainable forestry, and they were built with fewer features - when built well they didn't fail, but they weren't targeting high energy performance,…

Old growth wood is not inherintly stronger than plantation timber

Re: Hardened wood as a renewable alternative to steel and plastic

#272

Post by quixoticelixer- »

westurner wrote: post #14

From "Hemp Wood: A Comprehensive Guide" https://www.buildwithrise.com/stories/hempwood-the-sustainab... : > HempWood is priced competitively to similar cuts of black walnut. You can purchase 72" HempWood boards for between $13 and $40 as of the date of publishing. HempWood also sells carving blocks, cabinets, and kits to make your own table. Prices for table kits range from $175 to $300. Jul 5, 2021 […] > Is Hemp Woo…

Why not just use wood?

Re: Hardened wood as a renewable alternative to steel and plastic

#273

Post by rstuart4133 »

tristor wrote: post #63
chrisweekly wrote: post #57

Earlier quoted context omitted.

Time is a critical factor (ie, the "yr" in your metric). Bamboo grows _incredibly_ fast.

density (a critical factor of hardness) is normally inversely correlated to growth speed. Faster growing woods/plants are softer.

It takes 4-5 years to grow according to the article, and you can make Strand Woven Bamboo out of it. You can get a feel for the hardness of Strand Woven Bamboo here:

    https://planettimbers.com.au/2014/06/25/timber-wear-tear-and-hardness-including-janka-ratings/
Quoting:

    "Even though a Janka rating of 8 is considered ‘hard’,
    many Australian timber species achieve ratings of 12
    and above."
Strand Woven Bamboo has a Janka rating of 14.

As it happens I live in Australia, and so have tried to bang the odd nail into an old house, which are often made from Australian hardwood. Almost all of us live in new houses made from pine, and so all make the same mistake. If you are lucky, and after more than a few bent nails, some old codger will take pity on you and tell you it isn't possible. You have to pre-drill.

Re: Hardened wood as a renewable alternative to steel and plastic

#274

Post by ummonk »

jaclaz wrote: post #254
ummonk wrote: post #235

Earlier quoted context omitted.

Yeah I suspect they're comparing to cutlery knives out of the box - without any extra sharpening.

Not only, a "good" knife can be measured by its sharpness (and still the 3x sounds very little scientific) but also by the durability of its sharpness, there is a a youtube channel[0] by a guy that makes blades out of "everything" and they are actually sharp, but how much do they last (and last sharp enough) is unsaid, and in the end of the citation it seems like they propose these HW knife as a replacement for plast…

Yeah, and with a Brinell hardness of just 31 I doubt knives made out of this material would hold an edge that well.

Re: Hardened wood as a renewable alternative to steel and plastic

#275

Post by gnramires »

martythemaniak wrote: post #5
nico_h wrote: post #2

Can't read the article. How energy efficient and environmentally friendly is the hardening process compared to making steel? And is it a "in 20 years" thing again, like all new battery tech?

A general note: in a world of super cheap solar or wind, energy efficiency doesn't matter as much. It's cheap because In many instances, the end product is the "battery". A desalination plant can be run when the sun is out and the end product (clean water) can be stored and used. In this instance, the hardening step stores energy in the final product. Just run that step at the right time.

That's a common misconception; energy will matter anyhow.

It's useful to think of industry as a three factor limitation of energy, materials and intelligence[1] -- you are sort of always limited by one of them. If energy was of literal no concern, we could promptly utilize very inefficient carbon capture or even synthesize elements. Solar energy still has significant costs in labor (what I call intelligence) and materials, both of which are finite. We will always as a civilization be managing those factors, even with a seemingly unlimited source like a feasible fusion reactor (which would require an advanced highly costly and finite reactor to produce energy) to solar panels (which outsource the fusion to some 150 million km away producer :) )

A quick googling gives me about 24 MJ/kg for steel production. A compression cycle with, for example, 1cm of displacement would need to exert 2.4 GN or about 24 million tons of kg-force over a 1kg sample to use equivalent energy, which I believe is far above any press in existence.

[1] Indeed we know the first two are equivalent via E=mc^2 , however this conversion constant is essentially prohibitive outside of stellar nucleus. We also know the third one, intelligence, can be built from raw materials and energy, so there's also a conversion factor there.

Re: Hardened wood as a renewable alternative to steel and plastic

#276

Post by jnmandal »

account_b wrote: post #55
jnmandal wrote: post #36

Earlier quoted context omitted.

This is pretty clear to me too. We survive on stored energy borrowed from the past. Energy and growth are basically finite. We do need to cut down. We also need to develop tech (weather technique or technology) to reconstitute waste and refuse into the inputs for our food, buildings, transportation, etc.

> We survive on stored energy borrowed from the past. It's worse than that: We fully rely on borrowed time ! Natural geological cycles to restore surface phosphorus span many thousands of years. Our current agriculture (food production) critically depends on mineral phosphorus, which may be exhausted in just four or five decades. And we retain none of that, but flush our soils into the oceans (partially through the t…

> no one wants to lobby for collecting people's shit, while everything else goes full Star Trek.

Ironically in Star Trek, the food from the replicator is made from human waste or that's what they say in recent seasons anyways.

I am optimistic about the ability for us to recycle human waste despite the lack of popularity though. Most people have no idea what goes on at water/sewage treatment facilities and they don't really care. Even with no regulation or subsidy, it will eventually become profitable to recycle this waste b/c of geopolitical issues like you mentioned.

I'm pretty worried that we wont be able to cut back on consumption though and will end up buried in piles of our own junk.

Re: Hardened wood as a renewable alternative to steel and plastic

#278

Post by lillecarl »

MisterBastahrd wrote: post #50
sfink wrote: post #12

I've been intrigued for a while about various modified wood technologies (eg hardened wood, transparent wood), but I'm always disappointed because it usually ends up just being a minor support structure for a very non-wood material (generally epoxy). This one shows a compression step, so maybe it's different, but I'd really like more info on whether this is actually renewable or sustainable in any interesting sense.…

Reminds me of the one video I saw of this man spraying different things with some sort of polymer that was virtually unbreakable. He'd spray a cinderblock wall and then hit it with a sledgehammer. The wall would break, but the polymer would hold... so yay? That said, It seems like the sort of thing you'd want to spray asphalt shingles with.

https://www.youtube.com/watch?v=DWkYRh6OXy8

Remember that everything that's always outside will be subjet to death by the sun.

Re: Hardened wood as a renewable alternative to steel and plastic

#279

Post by the_other »

spfzero wrote: post #79
the_other wrote: post #31

Earlier quoted context omitted.

When Greta talks to the public sphere about government failing its climate responsibility, this is the kind of stuff she’s talking about. It’s easy to assume we “just” need subsidies and incentives (or the ending of same) for “green” solutions, but the problem is much larger than that. We need to be operating “sustainably” at every level, in between departments, across legislation. If regulation is blocking us, get i…

Shouldn't we make sure it's a good idea first?

I didn’t say skip it. I said speed up the process. Add more staff, bring deadlines closer, reduce systemic complexity.
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