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.
2026-04-25 19:00:50
One of the nice things about magnetic storage is that as long as the magnetic layer remains intact, the data it contains should stay readable pretty much indefinitely. That raises the prospect of recovering data from really old computer systems featuring magnetic memory, such as the 63-year old LGP-21 that [David Lovett] of Usagi Electric is currently restoring. Its magnetic memory disk is nothing amazing by modern standards, but after initial testing it seems to spin up and read data just fine, raising the question of what was left on the drive when it was last used, meaning what was in memory at the time.
Non-invasive data recovery here involves writing a program that will simply read the entire disk from beginning to end. Tracks 0 and 1 were found to be unreadable due to some kind of hardware issue, but track 2 could be backed up by looking at the output on the CRT, thus providing a track to use. Fascinatingly the LGP-21’s memory disks uses interleaved tracks to reduce the number of read/write heads as part of the overall cost-saving measures relative to the more expensive LGP-30. As you might expect, this slows down memory access a lot over its big brother.
Before any recovery attempt could begin, the Flexowriter typewriter that forms the user interface to the computer had to be given some serious maintenance, along with a few other components like a switch and the paper tape reader. This restored the ability to even properly enter data and receive output instructions.
The subsequent effort to recover the stored data involved a bootstrap program that got loaded into memory, after which the remainder of the program was loaded from paper tape. Following this everything worked swimmingly, though with the caveat that with not even a floppy drive to use, the raw hexadecimal data was hammered out on paper with the Flexowriter over the course of 1.5 hours.
This data will now be scanned in and OCR-ed into something that can hopefully be easily analyzed. Hopefully we’ll know before long what this system was last used for.
2026-04-25 16:00:46
Once upon a time, not every computer lived in a vertical “tower” case. Many decades back a horizontal arrangement was a popular choice, sometimes just referred to as the “desktop” style. [PuTaTuo] is helping to bring it back, with this amazing 3D printed case design.
The case is designed to suit mini-ITX motherboards, while supporting standard ATX-size power supplies. The printed components are all designed to measure less than 220 mm in any dimension to ensure they can easily be produced on smaller printers. The case has a 3.5″ drive bay cutout up front, which you can use for the front panel I/O or a floppy drive if you’re super-retro like that. The front panel is otherwise relatively simple, with buttons for power and reset as well as power and SSD status LEDs.
Assembly is via M3 hardware and heat set inserts. If you’d like to print your own, you can grab the files from Thingiverse or Printables depending on your taste.
We’ve featured some great 3D printed cases over the years, like this colorful build that focuses on ease of access and servicing. The cool thing about designing your own case is you can optimize it to suit your own desires, and customize it to look as cool as you need it to be.
I Designed and 3D-Printed a Retro Style ITX PC Case
byu/Potatozeng in3Dprinting
