0-_-0 1 hour ago

This made me wonder about a 3D printer alternative that builds things by folding a thin sheet of metal into arbitrary shapes instead of extruding filament.

  • whilenot-dev 1 hour ago

    I made an artwork in 2013-ish, where I attached an aluminum foil to a good DC motor. I mounted it from the ceiling with 2 stepper motors to control height and one orthogonal axis. The motor would unwind the foil by accelerating quickly in either direction (CW/CCW). By changing directions it would also create folds and stabilize the emerging shape: https://imgur.com/a/gaRKGtQ

    I always imagined an additional stepper motor to cover an area like a delta 3D printer and liked to think about the difficulty in creating the 3D software, and the need to find a solution to simulate the unwinding-into-shape through some physical model.

    EDIT: unwinding GIF here: https://imgur.com/a/VP3gEiv

    • aradaelli 45 minutes ago

      Imgur is not working anymore in UK :(

goda90 32 minutes ago

>Robert Lang recommends laminating tissue paper on one or both sides of kitchen aluminum foil to make “tissue foil”, which for years he considered the ideal origami material.

The sculptor Kim Beaton likes to champion foil as a "metal clay" for sculpting. Keep it full of air pockets and it's easy to shape. You can use hot glue to put parts together, and then cover it in other clays for fine details and coloring. She does quick demos for tour groups at Weta Workshop in New Zealand.

1970-01-01 1 hour ago

>Alternatively, though, it might be possible to stiffen the foil by making the equivalent of corrugated cardboard out of it, maybe using aqueous boric acid (US$1.70/kg according to Potential local sources and prices of refractory materials) or borax as the glue. The surface tension of water is ample to hold aluminum foil in place until the water dries.

Hello Amazon? Billion dollar idea here. This needs more attention. You could have fully recyclable aluminum boxes instead of cardboard. Imagine your box supply chain literally being a circle.

  • InitialLastName 1 hour ago

    That would be hell on everybody's box-cutters (and fingers). I already cut myself too often on shipping boxes.

  • bluGill 1 hour ago

    aluminum foil is generally not something you can recycle. Not that it can't be recyled, but the oxide to pure aluminum ratio is high and so you don't gain much since you need all the energy of refining in the first place to get back to something usable.

    Amazon needs stronger boxes than foil anyway. Cardboard is likely best for them.

jstanley 1 hour ago

> 50¢/m² is 50¢/kWp in a solar concentrator, or 0.05¢/Wp, which is noticeably cheaper than photovoltaic cells, currently around 18¢/Wp, 360 times more expensive.

A photovoltaic cell is a solar panel, and a piece of aluminium does nothing, am I missing something here?

dofm 1 hour ago

Photographers and cinematographers are like: ohhh let me sit you down and tell you all about my love of blackwrap.

Aluminium foil is amazing stuff. Aluminium foil adhesive tape, in particular, is incredibly useful.

Being a multi-domain kind of geek the random tapes section of my tool drawers also contains mylar tape and fashion tape (or "tit tape" as a friend calls it) but the aluminium foil tape has proved to have many useful applications.

delichon 2 hours ago

I appreciated the paean to aluminum foil in Project Hail Mary where (spoilers) the hero uses it as bowling pins and to reproduce astrophage to eventually save two worlds. It's right up there in the pantheon of useful things with duct tape.

t1234s 2 hours ago

This was on S01E01 of How It's Made. Probably one of the best segments in the shows history.

badc0ffee 59 minutes ago

It's non-toxic and food safe, and yet a significant number of people on the internet still act like it's poison that will give you Alzheimer's. I wonder how many of those people touch their lips to the lid of an aluminum beverage can. Or how they might bake a lasagna at home.

  • ceejayoz 30 minutes ago

    I've only seen people concerned with it in antiperspirants, where it's a salt. (And to be clear, I think it's BS.)

    As with NaCl, it's at least possible that the salt and the pure-ish variant aren't quite the same thing.

  • br0ceph 17 minutes ago

    i heard aluminum food containers are often coated with toxic liners, like plastics, bpa, and pfas. If Alzheimers isnt a risk with pure aluminum metal, id say those liners are a huge risk. Are kitchen foils coated? Im pretty sure cans are most of the time.

vessenes 2 hours ago

I was enjoying the ADHD hyper focus writing, kind of following along, then:

  > If we figure that the foil can meaningfully change direction every 20 μm, then we might think of an aluminum-foil machine as being made of “moving parts” on the order of 1000 μm² (50 μm × 20 μm), 1000 “parts” per square millimeter of foil; a roll of kitchen aluminum foil is enough to fabricate some 4 billion “parts”. A bootstrapping compiler might require 100 000 parts and thus a square centimeter of aluminum foil, cut and folded around into a shape a couple of millimeters in diameter. If it were doing only one thing at a time, and needed 10 seconds to construct/assemble each moving part, it would take about 12 days to recompile itself. This is probably adequately fast, barely, but probably not adequately robust against errors. It would probably be better to design it to have more parts and do many things at once, enabling it to be faster and correct errors.

Um, what? I'd like to see a sketch of this 100,000 part compiler very much. I have no idea what he/she is talking about here, in the slightest. But I am intrigued!

  • wgd 2 hours ago

    I've read a lot of his other writings so that context might be informing my reading here but it sounds like he's pretty straightforwardly discussing the potential of aluminum foil as a uniform-feedstock-slash-construction-material for a hypothetical self-reproducing microfabricator.

codazoda 1 hour ago

I just skimmed and read parts but I really enjoyed reading this. It's like my own handwritten notes which are just stray thoughts about a subject. Maybe I should publish more of those and I love the idea of just musing about a single thing, like Aluminum Foil (though it's very interesting stuff).

unchocked 1 hour ago

Worth noting that aluminum is the most abundant metal of the Moon’s highland geography, thus excellent for bootstrapping beyond Earth.

0xWTF 1 hour ago

Amazing. This reads like someone left Hunter S. Thompson alone with a roll of Reynolds Wrap.

Sharlin 1 hour ago

Aluminum is honestly a miracle material that has no business being as inexpensive as it is (of course, this is only since the invention of the Hall–Héroult process, before which aluminum was one of the most expensive metals known despite making up ~8% of the crust).

  • ceejayoz 27 minutes ago

    Yup. The very tip of the Washington Monument was made of aluminium, which made it faaaaaancy. Two years later, not so much.

secretslol 1 hour ago

Another thing not mentioned on there about aluminium foil is how clean it is. We work with a laminar flow hood and pull a fresh layer of foil anytime we are working to create a clean base to work on. I can guarantee you that if you run a swab over a fresh sheet of foil and smear it onto sterile nutrient agar that it won't grow anything - that said, we use costco foil which is thicker gauge and not the budget thinner stuff which is definitely inferior.

  • MezzoDelCammin 16 minutes ago

    any tips on how to reliably get that "thicker gauge" one? I've been craving it since maybe 20y ago when I got a roll from my old stint in a restaurant. I've tried buying some rolls by "heavy duty" labels and these days it's just as likely to be one of those thin "look at it funny and it tears".

proee 2 hours ago

Im interested in using honeycomb aluminum panels for some projects but curious why its so freaking expensive?

IshKebab 2 hours ago

This is pretty much just rambling about how amazing aluminium foil is because it's so thin and that might enable all sorts of wonderful imaginary applications. Very HN. It's aluminium foil.

  • post-it 2 hours ago

    That's the neat part though, isn't it? It's a product that's so good that there's no everyday alternatives to it. I was researching cat litter options recently and cat owners do a lot of thinking and talking about litter, because there's a variety of different materials, none of which are solidly better than all others in all situations. But aluminium foil is so good that we don't even think about it, because it's by far the best product for every application that we use it for.

  • Forgeties79 2 hours ago

    You sound like someone who hasn't explored the upper limits of what aluminum foil can solve!

    • whynotmaybe 1 hour ago

      Has a kid, my mom used to pack my lunch in aluminium foil and everyday was a challenge of trying to make the perfect aluminium ball and throw it in the trashcan[1] on the first try!

      1. Recycling was a vague concept in the 80s & 90s

      • bluGill 1 hour ago

        Your local recycler probably doesn't want al foil even today when recycling is a big thing.

    • IshKebab 1 hour ago

      Read this guy's ramblings and give me one cool application that he has found. Lots of "maybe it could do this!" and "it can do <completely useless thing>!"

      • Forgeties79 27 minutes ago

        Aluminum foil makes a great, cheap light bounce for photography on the fly. Your photos will instantly look better either reflecting to the back of their head 180 from shot, or as a fill for their face.

  • nyeah 1 hour ago

    What's really thin is the oxide layer on the surface

    https://en.wikipedia.org/wiki/Anodizing

    When exposed to air at room temperature, or any other gas containing oxygen, pure aluminium self-passivates by forming a surface layer of amorphous aluminium oxide 2 to 3 nm thick,[4] which provides very effective protection against corrosion. Aluminium alloys typically form a thicker oxide layer, 5–15 nm thick, but tend to be more susceptible to corrosion.

    • wolfi1 1 hour ago

      it usually is not only aluminium oxide but a mixture of aluminium oxide and aluminium hydroxide if it is normal (read: moist) air