Viewing profile — kragen

Your response comment saying "I have now read all of that" was posted 11 hours after I linked you to a bit over 120,000 words of notes on the topic you were asking about (according…

Yeah, I do have some ideas: https://dernocua.github.io/topics/digital-fabrication.html https://dernocua.github.io/topics/self-replication.html https://dercuano.github.io/topics/sel…

By "here" do you mean "the internet"? Are you trying to discourage people from sharing their calculations and observations with one another if they don't personally interest you ? …

I wasn't suggesting using it for shipping boxes, but rather for things like robot arms.

"Plastic" is not a material; it's a property or state of many unrelated materials. It doesn't make any more sense to say that plastic is a risk to health than to say that liquid is…

Only if you do it in an oxidizing atmosphere. Though aluminum is very liberal about its definition of "oxidizing atmosphere".

It's not that my argument is flawed so much as that it depends on some basic background knowledge about processes like corrosion and solvation. Lacking that knowledge, you're bette…

That's SPIF ("single-point incremental forming"), which is mentioned in passing in my note: > These can presumably be removed, permitting traditional SPIF processing of raw foil by…

I'm not sure, but I think that normally it reacts with phosphate ions to form aluminum phosphate rather than leaving the body.

Also true of teflon, aluminum oxide, and Earth as a whole. Perfluorooctanoic acid, by contrast, is not mostly harmless.

You're welcome! It's a pretty broad term, with a lot of possibilities, but generally I mean a machine which, given a design for a machine in the form of digital data, can build a w…

I'm not sure, but I suspect cooling requirements also enter into consideration.

Oh, thanks! You are surely correct; I was puzzled about how something as relatively inert as pizza dough could corrode aluminum at multiple microns per hour, but electrolysis can d…

And today... I shall TAKE OVER THE WORLD, Igor!

Aluminum is a major component of all soils, and soluble aluminum salts have been used in medicine and dyeing since ancient Greece, probably since ancient Egypt. They have been used…

Well, "Dercuano" sounds like "Dirk One Oh" in English, so clearly the sequel should be "Dirk Two Oh". And "Dernocua" is the properly formed vesre of cuaderno , unlike "Dercuano", w…

It does not, but aluminum oxide is even more of a "forever chemical" than teflon is, though less so than, for example, the nitrogen that constitutes 78% of the atmosphere.

Let's see if this is a quantitatively plausible concern. https://en.wikipedia.org/wiki/Aluminium_chloride says orl-rat LD₅₀ of AlCl₃ is 380mg/kg, which is 20.2% aluminum by weight,…

I do not currently have a sketch of a matter compiler, just a rough estimate that most of its parts count would probably be RAM, and that it probably needs several kilobytes of RAM…

This is very impressive!

Thanks! I keep unintentionally using https links to canonical.org since basically the whole web is https now. Fixed.

I had no idea about that!

Thank you.

I wasn't expecting to see Dernocua at the top of HN today with 53 comments. You can download Dernocua as a whole from http://canonical.org/~kragen/dernocua/ if you're interested. I…

Maybe not for everybody, but I recall hearing that certain military units, students, and government officials were required to get covid vaccinations already in '20. Maybe he heard…