Blocky tread, yellow hub-- yep, it looks like LEGO

10″ LEGO Tyre Is Practical Nostalgia

September 29, 2025 by Tyler August 6 Comments

If there’s one thing that has come to define the generations after the baby boom, it’s probably nostalgia. It’s heavily marketed and weaponized by the market: yearning for better, simpler times seems to be a core thread of the consumer economy these days. [Makerneer] combined his xilennial love of LEGO bricks with the flat tires on his log splitter to produce a 10″ TPU tyre will never go flat, and provide a dopamine release every time he sees it.

The tyre is a custom model to fit his particular rims, but he does provide STEP and F3D files if you’d like to try modifing it for your own purpose — they’re at Step 6 of the Instructable. Props to [Makerneer] for truly open-sourcing the design instead of just tossing STL files online. His build log also takes the time to point out the ways he had to modify the LEGO tyre profile to make it amenable to 3D printing: notably chamfering some of the tread pattern to eliminate bridging, which is a bit of a no-no with TPU.

As you can see in the (unfortunately vertical) demo video below, it’s a bit quite a bit squishier than a regular run-flat tyre, but that was part of [Makerneer]’s design goal. He didn’t like how rigid the non-pneumatic tyres he’d tried were, so endevoured to design something himself; the whole LEGO thing was just for fun. If you wanted to replicate this tyre with a bit less skoosh, you need only tune the infill on your print.

While only time will tell how long this LEGO-inspired add-on will continue adding whimsy to [Makerneer]’s log-splitting, we have tests to show it will outperform any other plastic he might have printed. This project is probably more practical than a 3D printed bicycle tyre, which doesn’t even have the side benefit of whimsy. Continue reading “10″ LEGO Tyre Is Practical Nostalgia” →

How Many Phones Sport A 5 And 1/4 Diskette Drive? This One.

September 27, 2025 by Tyler August 12 Comments

It all started with a sarcastic comment right here on Hackaday.com: ” How many phones do you know that sport a 5 and 1/4 inch diskette drive?” — and [Paul Sanja] took that personally, or at least thought “Challenge accepted” because he immediately hooked an old Commodore floppy drive to his somewhat-less-old smartphone.

The argument started over UNIX file directories, in a post about Redox OS on smartphones— which was a [Paul Sajna] hack as well. [Paul] had everything he needed to pick up the gauntlet, and evidently did so promptly. The drive is a classic Commodore 1541, which means you’ll want to watch the demo video at 2x speed or better. (If you thought loading times felt slow in the old days, they’re positively glacial by modern standards.) The old floppy drive is plugged into a Google Pixel 3 running Postmarket OS. Sure, you could do this on Android, but a fully open Linux system is obviously the hacker’s choice. As a bonus, it makes the whole endeavor almost trivial.

Continue reading “How Many Phones Sport A 5 And 1/4 Diskette Drive? This One.” →

Vertical Solar Panels Are Out Standing

September 25, 2025 by Tyler August 91 Comments

If you’re mounting solar panels, everybody knows the drill, right? Point them south, angled according to latitude. It’s easy. In a video which demonstrates that [Everyday Dave] is truly out standing in his field, we hear a different story. [Dave] has a year’s worth of data in his Solar Panel Showdown that suggests there are good reasons to mount your panels vertically.

Specifically, [Dave] is using bifacial solar panels– panels that have cells on both sides. In his preferred orientation, one side faces South, while the other faces North. [Dave] is in the Northern Hemisphere, so those of you Down Under would have to do the opposite, pointing one face North and the other South.

Since [Dave] is far from the equator, the N/S vertical orientation beats the pants off of East-West facing panels, especially in winter. What’s interesting is how much better the bifacial panels do compared to the “standard” tilted orientation. While peak power in the summer is much better with the tilted bifacial panels (indeed, even the tilted single-sided panels), in winter the vertical N/S panels blow them out of the water. (Especially when snow gets involved. Vertical panels don’t need sweeping!)

Continue reading “Vertical Solar Panels Are Out Standing” →

It’s A Bird! It’s A Plane! It’s… An Air Breathing Satellite?!

September 24, 2025 by Tyler August 18 Comments

The big problem with Low Earth Orbit is, oddly enough, air resistance. Sure, there’s not enough air to breathe in space, but there is enough to create drag when you’re whipping around the planet at 28,000 km/h (17,000 mph) or more. Over time, that adds up to a decaying orbit. [Eager Space] recently did a video summarizing a paradoxical solution: go even lower, and let the air work for you.

So called air-breathing satellites would hang out in very low earth orbit– still well above the Karman line, but below 300 km (186 miles)– where atmospheric drag is too dominant for the current “coast on momentum” satellite paradigm to work. There are advantages to going so low, chiefly for communications (less latency) and earth observation (higher resolutions). You just need to find a way to fight that drag and not crash within a couple of orbits.

It turns out this space isn’t totally empty (aside from the monoatomic oxygen) as missions have been at very low orbits using conventional, Xenon-fueled ion engines to counter drag. The xenon runs out pretty quick in this application, though, and those satellites all had fairly short lifetimes.

That’s where the air-breathing satellites come in. You don’t need a lot of thrust to stabilize against drag, after all, and the thin whisps of air at 200 km or 300 km above ground level should provide ample reaction mass for some kind of solar-electric ion engine. The devil is in the details, of course, and [Eager Space] spends 13 minutes discussing challenges (like corrosive monoatomic oxygen) and various proposals.

Whoever is developing these satellites, they could do worse than talk to [Jay Bowles], whose air-breathing ion thrusters have been featured here several times over the years.

Continue reading “It’s A Bird! It’s A Plane! It’s… An Air Breathing Satellite?!” →

3D Printed “Book” Demonstrates Mechanical Actions

September 24, 2025 by Tyler August 22 Comments

A book of mechanical actions is a wondrous thing — mechanically inclined children have lost collective decades pouring over them over the generations. What could possibly be better? Why, if the mechanisms in the book were present, and moved! That’s exactly what [AxelMadeIt] produced for a recent video.

Being just four pages, you might argue this is but a pamphlet. But since it takes up a couple inches of shelf space, it certainly looks like a book from the outside, which is exactly what [AxelMadeIt] was going for. To get a more book-like spine, his hinge design sacrificed opening flat, but since the pages are single-sided, that’s no great sacrifice.

At only 6 mm (1/4″) thick, finding printable mechanisms that could actually fit inside was quite a challenge. If he was machining everything out of brass, that would be room for oodles of layers. But [Axel] wanted to print the parts for this book, so the mechanisms need to be fairly thick. One page has a Roberts linkage and a vault-locking mechanism, another has planetary gears, with angled teeth to keep them from falling out. Finally, the first page has a geneva mechanism, and an escapement, both driven by a TPU belt drive.

All pages are driven from an electric motor that is buried in the last page of the “book”, along with its motor, battery, and a couple of micro-switches to turn it on when you open the book and off again when you reach the last page. Rather than a description of the mechanisms, like most books of mechanical actions, [Axel] used multi-material printing to put lovely poems on each page. A nice pro-tip is that “Futura”, a font made famous by flying to the moon, works very well when printed this way. If you just want to watch him flip through, jump to 8:00 in the video.

This reminds us of another project we once featured, which animated 2100 mechanical mechanisms. While this book can’t offer near that variety, it makes up for it in tactility.

Continue reading “3D Printed “Book” Demonstrates Mechanical Actions” →

Who Wants A Rusty Old Smartphone?

September 24, 2025 by Tyler August 57 Comments

If we’re talking about oxidized iron… probably nobody. If we’re talking about Rust the programming language, well, that might be a different story. Google agrees, and is working on bringing the language into Android. That’s not enough for [Paul Sanja], who has the first Redox OS smartphone.

Redox OS is a Unix-like operating system written entirely in Rust, and somehow we haven’t covered it until now. Unlike Asterinas, a project to recreate the Linux kernel in Rust, Redox has few pretensions of being anything but its own thing, and that’s great! On desktop, Redox has a working windowing system and many utilities, including a basic browser in the form of NetSurf.

It’s claims to be source-compatible with Linux and BSD programs, and partially POSIX compliant. A certain someone around here might want to try it as a daily driver. The header image is a desktop screenshot, because there’s more to see there and it fits our aspect ratio.

On smartphones, it… boots. Some smartphones, anyway. It’s actually a big first step. That booting is possible is actually thanks to the great work put in by the Postmarket OS team to get Uboot working on select android devices. That uboot loader doesn’t need to load the Linux-based Postmarket OS. It can be used for anything compatible. Like, say, Redox OS, as [Paul] shows us.

Of course, Redox OS has no drivers for the touchscreen or anything else, so at the moment that rusty smartphone can only boot to a login screen. But thanks to Rust, you can rest assured that login screen hasn’t got any memory leaks! Jokes aside, this is a great start and we’re hoping to see more.

Redox is a promising project on mobile or desktop, and its development seems a much better use of time and effort than fighting over Rust in the Linux kernel.

Blue Alchemist Promises Rocket Fuel From Moon Dust

September 22, 2025 by Tyler August 16 Comments

Usually when an alchemist shows up promising to turn rocks into gold, you should run the other way. Sure, rocket fuel isn’t gold, but on the moon it’s worth more than its weight in the yellow stuff. So there would be reason to be skeptical if this “Blue Alchemist” was actually an alchemist, and not a chemical reactor under development by the Blue Origin corporation.

The chemistry in question is quite simple, really: take moon dust, which is rich in aluminum silicate minerals, and melt the stuff. Then it’s just a matter of electrolysis to split the elements, collecting the gaseous oxygen for use in your rockets. So: moon dust to air and metals, just add power. Lots and lots of power.

Melting rock takes a lot of temperature, and the molten rock doesn’t electrolyse quite as easily as the water we’re more familiar with splitting. Still, it’s very doable; this is how aluminum is produced on Earth, though notably not from the sorts of minerals you find in moon dust. Given the image accompanying the press release, perhaps on the moon the old expression will be modified to “make oxygen while the sun shines”.

Hackaday wasn’t around to write about it, but forward-looking researchers at NASA, expecting just such a chemical reactor to be developed someday, proposed an Aluminum/Liquid Oxygen slurry monopropellant rocket back in the 1990s.

That’s not likely to be flying any time soon, but of course even with the Methalox rockets in vogue these days, there are appreciable cost savings to leaving your oxygen and home. And we’re not biologists, but maybe Astronauts would like to breathe some of this oxygen stuff? We’ve heard it’s good for your health.