Thanks! I haven’t actually published these pieces yet. (Well, the slide-glide cyclide thing was published by someone else, but I think it was later taken down–there may be plans for the original mathematician to sell them?) The puzzle box is just a little too kluged together to really publish; I modified a lot of things after the fact to get it together, and I’m not comfortable publishing it in that state, but I also don’t really want to put in the work to finish it. The kaleidoscope would actually be okay, but it’s limited–it’s a bit tricky to actually cut the mirrors, and it really only works to reflect things right up against it. I want to design an adapter for it that will hold an acrylic sphere (which you can get inexpensively from China) so that you can use it to look at scenes as well. But I haven’t actually gotten around to that yet either. I’ll give some thought to publishing it as-is, though.

I dunno. I agree with this to some extent for sure–I don’t print a lot of the meme models that are everywhere on 3d printing forums. But there are toys that would not exist without 3d printing that I think are pretty great.

I designed a kaleidoscope that reflects things not to tile a plane, but instead to tile the surface of a disdyakis triacontahedron: https://imgur.com/gallery/i-made-kaleidoscope-P4atHey I had to cut the mirrors from acrylic by hand, but the templates for them and the shell that holds them in place are all 3d printed. And that thing is a pretty great toy.

This thing: https://imgur.com/gallery/make-of-cyclidial-iris-by-vergo-henry-segerman-XHN4MC0

is a math sculpture that I didn’t design, just printed, but it’s completely beautiful, and it’s had real staying power as both a toy and a decoration. It sits out on our coffee table all the time, but my niece plays with it every time she’s over here.

And this puzzle box I designed: https://imgur.com/gallery/i-made-puzzle-box-nieces-birthday-U1q408R

was a big hit with her too. I’m not sure if she’ll continue to play with it long-term, but based on my own tendencies as a kid, I think she might end up investigating the mechanisms involved for some time to come.

Things that you could buy at the store you’re generally better off buying at the store. But there are things it’s not economical to mass produce, and it never used to be possible to design and make your own toys. Both ideosyncratic toys and bespoke toys are pretty great uses of 3d printing in my opinion.

“If only I’d programmed the robot to be more careful what I wished for. Robot, experience this tragic irony for me!”

Really! I find that fascinating.

When I try to think of a tune (often because I haven’t recalled the lyrics yet and am still trying to identify the song), I am just listening to the song in my head, trying to think of the notes and instrumentation of the next bit. I hear it, like a recording.

When I try to throw something–I said basketball because I figured it would be more relatable, but the sport I actually played was Ultimate (Frisbee, but that’s a trademark, so the sport is just Ultimate)–I’m picturing the path of the disc, how it will arc on the wind, the precise angle, how to roll it off my fingers, how long it will be in the air and how far to lead the runner. It’s a struggle to even come up with words for it now. It all feels visceral, the same as thinking how to reach my hand out to touch a glass on a table.

It’s hard for me to imagine using words for those kinds of things because words are so vague and general. Words deal with categories we impose on the world, rather than the world as it is. Like, I learned to juggle as a teenager; I could never do that if I had to use words to think about every way to maneuver my arms and how the balls would land and so forth. I just have to reach where the ball is going to be, and throw where my hand is going to be. When I first learned Mills’ Mess, I got it mixed up a bit (because I was learning from a VHS tape), and I had an extra throw in there. It took me quite a while to figure out how I mixed it up, and how to do it without that extra throw. But it was a spatial puzzle. I wouldn’t even know how to convey the issue in detail without just doing it.

I dunno. I shouldn’t be surprised that people’s inner lives are very different, but this particular point confounds me a bit.

When you’re thinking about how to throw a basketball to get it through a hoop, do you use words for that?

When you are thinking of the tune to a particular song, is that in words?

I think a lot of people overestimate the role of words in thinking. There’s a lot of non-verbal thought.

I think this might be more what they’re looking for.

https://imgs.xkcd.com/comics/random_number.png

Yes, to an extent they do different things, but that’s not what the person you were replying to was talking about. For several years there was this idea that “left-handed people are right-brain dominant, and right-handed people are left-brain dominant.” And along with that went this whole astrology-tinged thing about the right brain being the creative half and the left brain being the analytic half and whatnot. It’s pretty much nonsense.

The “Scunthorpe Problem” strikes again!

Not as far as I know. Practically speaking there are several disadvantages–the slots limit the light on the markings, parallax effects can mess with the reading, it requires two full surfaces sliding against each other which increases friction, etc. Plus with a regular vernier scale you can see both sides of a line, which could give you a better sense of how they line up (“vernier acuity”). But in a case like this, where precision isn’t a top priority and ease of use might outrank it, I think there’s an argument to be made for it.

I wouldn’t have caught that the gallery link was wrong if you hadn’t mentioned not knowing how the tool was used, so thank you as well!

Yeah, it’s definitely not the most precise thing. It’s good to around ±1mm. I tried to measure 1.75mm filament with it, and it just reads 1, not even between 1 and 2, so for critical measurements the physical matches are definitely better.

And yeah, here the vernier effect is not giving very high precision; it’s just giving a way to space the marks out enough to be printable, but indicate movements that are as small as a printed line.

Vernier calipers are absolutely ingenious, and it’s a shame that more people don’t know how to use them.

Sorry, just realized I also had the wrong link for the gallery that included photos of the tool in use! I edited the post, but here’s the corrected version of that: https://imgur.com/gallery/moire-vernier-radius-gauge-design-3d-printing-ajy0GBg

Sorry all! I meant to post a video of the moire/vernier effect in action, which is the most eye-catching part of the whole project, as the main image for the post, but it didn’t upload. And now when I try to edit in a link, or post a link to it in the comments, it’s telling me “blocked URL.” But there’s a link on the printables page, and the version with the older version is in the imgur gallery which is linked.

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So, the EPA sets emissions rules for the country, on the grounds that it would be problematic for industry if there was a patchwork of 50 different sets of rules about this stuff. California got the feds to agree to let them set their own stricter limits, though, and allowed other states to sign on to also use California’s rules if they wanted to, which several did.

So I think what’s happening here is that the waivers are being rescinded. They’ve been in place for ages (at least 50 years, I think?) so it’s a huge departure from business as usual, but you know how Trump loves stomping on norms.

This article has some of the relevant points: https://www.npr.org/2025/05/22/nx-s1-5387729/senate-california-ev-air-pollution-waiver-revoked

Seriously. This is exactly what people object to about Windows Recall. In its re-released version at least it’s opt-in for now, but it’s still eerily close to this.

They’re not saying that slow growth is definitely evidence it’s exponential. They’re saying that slow growth doesn’t prove that it isn’t exponential, which seemed to be what you were saying.

It’s always hard to identify exponential growth in its early stages.

Good news on the latter front, actually: https://www.tomshardware.com/tech-industry/tsmc-expands-investments-in-the-u-s-to-usd165-billion-with-new-fabs-and-r-and-d-center-a-closer-look

I guess I sort of agree? It’s a bit tricky to get it set up, for sure. Even just installing windows is probably beyond the average user, and this has a few more quirks and gotchas than normal.

E.g., in IoT LTSC 11 (which is what I’m actually currently using), when you connect a controller, it’ll bring up an error message about not having a handler for ms-gamebar, and fixing that calls for regedit. (One it’s fixed, though, it stays fixed.) It also got itself into a bit of a weird state during the initial installation where it wanted me to log in with a kind of account I don’t have, and while I was able to bypass that, I don’t think I did it in quite the right way, and it broke something in the install and I had to do an in-place repair install to fix it before it would install certain updates successfully. It was also failing to download the in-place repair install, so I had to look up how to do it manually using the install DVD I’d burned previously. But that fixed it, and it’s been fine since.

So, yeah, it’s got pitfalls and quirks and glitches. That’s also been my experience with other Windows installs, though, so it didn’t seem all that different in general.

But once you get those initial hurdles sorted out, it’s really just like normal Windows. Better, even, since it doesn’t have all the cruft built into it, like Cortana, Teams, OneDrive, start menu ads, nag screens about upgrading to 11, the Microsoft Store, etc. (Though you can add most of those if you really want them.) My aging parents aren’t willing to upgrade to 11 because they’re afraid too many things will have changed, and I’m thinking I’ll probably switch them to 10 IoT LTSC instead. I’ll just have to be careful to make sure everything they want to do works before I leave them to it. It still gets monthly security updates and everything.