2026-04-26 13:00:41
If you follow [Maker’s Muse] on YouTube, you know he’s as passionate about robot fights these days as he is about the tools he uses to make the robots. Luckily for us, he’s still got fame as a 3D printing YouTuber, as this has given him the platform to share his trade secrets for strong, robot-combat-worthy prints.
He fights robots in a ‘plastic ant-weight’ division, which restricts not only the weight of the robot but also the materials used. Not only must they be primarily plastic, but only certain plastics are allowed: PLA is in, but engineering filaments, Nylon, and TPU are out. Since necessity is the mother of invention, this has led to strong evolutionary pressure to figure out how to print the most impact-resilient PLA parts for armor and spinners.
He’s using the latest OrcaSlicer and shares the profile as a pay-what-you-want 3MF file. It’s all about solidity: a solid part with solidly fused walls and solidly linked layers. It makes sense: if you’re going to be hammering on or with these parts, you don’t want any internal voids that could either collapse or pull open.
The infill density is obviously 100%, and you’ll want a concentric pattern — this makes it look like you’re just printing walls, but it allows you to use another trick. To make sure those walls don’t all align, creating a potential weakness, OrcaSlicer’s “alternate extra wall” will put one extra wall every second layer. The extra wall causes the infill pattern to stagger and lock together.
Also helping lock it together, he’s playing with extrusion widths, with the suggested rule-of-thumb being the line width on the walls be one-half that of the internal fill — and as wide as possible. In his case, with a 0.4 mm nozzle, that means 0.4 mm wide walls and 0.8 mm for the infill. OrcaSlicer 2.3.2 also lets you play with specific flow ratios, allowing you to overextrude only the internals for strength, without overextruding on the walls and potentially ruining dimensional accuracy. He also irons all top surfaces, but admits that that’s mostly about aesthetics. The iron may make those layers a little bit stronger, though, so why not?
Would brick layers make these parts even stronger? That’s very likely; [Maker’s Muse] mentions them in the video but does not use them because they’re not implemented in-slicer, and he wants something accessible to all. On the other hand, this post-processing script seems accessible enough for our crowd.
This video/profile is exclusively about fully-solid parts. When you want strong parts that aren’t fully solid, it looks like the answer is walls.
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2026-04-26 10:00:37
A lot has been made about a post-quantum computer future in which traditional encryption methods have suddenly been rendered obsolete. With this terrifying idea in mind, it’s reassuring to see some recent pushback to the idea with some factual evidence. In a recent blog post by [Filippo Valsorda] – a cryptography engineer – the point is raised that 128-bit symmetric keys like AES-128 and SHA-256 are at risk of being obliterated in a post-quantum future.
Rather than just taking [Filippo]’s word for it, he takes us through a detailed explanation of the flawed understanding of Grover’s algorithm that underlies much of the panic. While it’s very true that this quantum search algorithm can decrease the amount of time required to find a solution, the speed-up with a single thread is quadratic, not exponential. While asymmetric cryptography systems like ECDH, RSA, and kin are very much at risk courtesy of Shor’s algorithm, the same is not true for symmetric systems.
An interesting detail with Grover’s is also that you cannot simply run a search in parallel to get a corresponding speed-up, as it’s not a parallel problem. Barring a breakthrough that replaces Grover’s with something that lends itself better to such a parallel search, it would seem that we won’t have to abandon classical encryption any time soon.
Incidentally, even for Shor’s algorithm, there are still some hold-ups. Current quantum computers are not even able to factor 21 yet. Meanwhile, supposed quantum computing breakthroughs are being trolled with a Commodore 64.
2026-04-26 07:00:31
Although 3D printing it a great tool for making all sorts of things, the nature of the plastics used in most desktop FDM printers means it isn’t the first tool most would think of to build an internal combustion engine. [Alexander] is evidently not most people, as he’s on his third generation 3D printed engine.
There are 3D printed pumps to distribute coolant water and oil, plus some clever engineering in the head to make sure they don’t mix — a problem with a previous iteration. As you probably guessed, the engine isn’t fully printed. Assembling it requires add-on hardware for things like bearings, belts, and filters.
But it’s still impressive just how much of this beast is actually made of plastic. Not even fancy engineering plastic, either — there are a few CF-Nylon parts, but most of it is apparently good old ASA and ABS.
If you’re looking for “cheats”, the plastic engine block does get a stainless steel sleeve, and the head is CNC’d aluminum, but we hesitate to call anything that gets a homemade engine running a “cheat”. It’s hard enough using all the ‘right’ materials. Just like another 3D printed engine we featured, the carb is also an off-the-shelf component.
Still, it’s the dancing bear all over again: it’s not how well it runs that impresses, but the fact that it runs at all. We’ve also seen hackers use 3D printing to make steam engines, hot-air Stirling engines, and electric motors— all with varying amounts of non-printed parts.
2026-04-26 04:00:51
Have you ever looked out across the rooftops of a city and idly gazed at the infrastructure that remains unseen from the street? It seems [varunsontakke80] has, because here’s their project, harvesting energy from the rotation of a rooftop ventilator.
The build is a relatively straightforward one, with a pair of disks with magnets attached being mounted on the ventilator shaft inside its dome. A third disk sits between them and is stationary, with a set of coils in which the magnets induce current as they move. A rectifier and charge circuit completes the picture.
This appears to be part of a college project, but despite searching, we can’t find any measure of how much power this thing generates. We’d be concerned that it might reduce the efficiency of the ventilator somewhat. There will be an inevitable tradeoff as power is harvested. Still, it’s a neat use of a ubiquitous piece of hardware, and we like it for that.
This hack is part of our 2026 Green Powered Challenge. You’ve got time to get your own entry in, so get a move on!
2026-04-26 01:00:55
Emergent properties include examples like murmurations of starlings which can’t be predicted from looking at a single bird, weather which can’t be predicted by looking at a few air molecules, and consciousness which can’t be predicted by looking at a neuron. Likewise, when adding a new tool to a workflow, emergent properties can show up as well. A group at Chicago University developed a robotic drawing tool and a few artists developed some unique drawing methods using it.
The robotic pen uses a pair of tendons to extend the working end out a certain amount. From there it uses a set of servos to can be programmed to revolve around in a defined path, making repeating movements while the artist makes larger movements over the paper. Originally meant for shading, small circles or simpler back-and-forth movements were preset, but with full control over the pen’s behavior the artist can shift focus away to other tasks within the creative process. A study with ten participants was done which showed artists coming up with novel ways of using a tool like this, and others reporting that it’s almost like drawing together with another person.
Looking for novel ways that humans can interact with computers and robots can often lead to surprising outcomes like this. Members of this group aren’t new to novel human interface devices either; they’ve also built a squishy dynamic button as well.
2026-04-25 22:00:05
Handheld consoles are great for gaming on the go, but who wants to hold onto things all the time? Would it not be easier to strap the game to your wrist? Well, not in its current form factor, but [LeggoMyFroggo], aka [
Chris Hackmann] has you covered, because he turned the Gameboy Color into a (relatively smart) watch.
Why “relatively” smart? Well, we say that because he’s using the original Game Boy Color CPU, a Sharp SOC based on the Z80 that is far less powerful than modern smartwatch platforms. That SOC is helped out by an RP2040 that translates the chip’s parallel RGB output into something a modern watch-sized display can comprehend via its PIOs. [Chris] refers to it as a “poor man’s FPGA” which isn’t a bad way of thinking about it in this context. Yes, he could have just stuck an emulator on that chip, but what’s the fun in that?
The controls are squeezed into the sides of the watch — the four face buttons on one side, and a tiny D-pad on the other — but that’s easy enough because this thing is 15 mm thick. Since [LeggoMyFroggo] is a purist, he insists on loading the games via cartridge, which does not help thin it out. Game Boy carts are not not watch-friendly, so the cartridges are custom PCBs that plug into an M.2 slot, but with the original (or at least compatible) ROM.
If it wasn’t for the cartridge slot, maybe a battery would have fit. But it doesn’t, which leads to our favorite part of the hack: the battery is in the watch strap. This is both kind of crazy, but also brilliant. The band is cast in silicone, so he’s able to embed a flexi-PCB inside. As for the watch body, that’s CNC’d out of 6061 aluminum before being anodized to a very Nintendo-esque purple.
[Chris] evidently has a soft spot for the Game Boy Color — we featured his FrogBoy re-imagining of the handheld a few years back. The project is just up on YouTube as of this writing, but the watch will join the FrogBoy on [Chris]’s GitHub so we can all get in on the fun once he’s finished the documentation.
