Quirky Electric Car Rides The Rails

April 19, 2026 by 17 Comments

We wouldn’t be surprised if you’d never seen the Spira before. The lightweight three-wheel vehicle is closer to a go-kart than a traditional car, and that’s before you even get to the foam body panels. But even the most niche of products enjoys a certain fandom, and [Matt Spears] certainly seems to love working on his Spira. His latest video documents the new modifications he’s made to the car in an effort to ride it on abandoned railroad tracks in the western United States.

His first attempt at riding the rails worked pretty well but he hit an obstruction at high speed which destroyed his front axle and damaged a few other parts on the vehicle, which gave him a perfect excuse to make some upgrades. He swapped the old rear axle out with one from a go-kart, complete with custom wheels and a new braking system. The drivetrain received an upgrade with a 5 kW electric motor, and although [Matt] planned on casting new wheels for the higher speeds, the chemicals he needed didn’t arrive in time. So, to test the new vehicle he repurposed some old wheels just to get the Spria back out on the tracks.

The test run went so well that [Matt] ended up pushing the vehicle farther than he had ever been on this abandoned rail, including over a questionable trestle and far out into the wilderness. Hopefully we’ll see more videos of [Matt] taking this car to explore even more remote places. In the meantime, take a look at some simpler, non-electric vehicles that are often used to explore abandoned rail lines in California.

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Modded Server PSU Provides Plenty Of Current

April 19, 2026 by 14 Comments

Most makers find themselves in need of a benchtop power supply at some point or another. Basic models can be had relatively cheaply, but as your current demands go higher, so does the price. [Danilo Larizza] has figured out an alternative solution—repurposing old server hardware to do the job instead.

The build is based around an HP Common Slot (CS) server power supply. They can be readily had for well under $50 if you know where to look. Even better, they can deliver over 50 amps at 12 volts, which happens to be a very useful voltage indeed. All you need to do is some minor mods.

A jumper on a couple of pins will get the power supply running, and with the addition of some terminals for your hook-up leads, you’re ready to go. As a hot-swappable single unit, the power supply is already outfitted with a ventilation fan to keep everything cool. If so desired, you can even make some further mods to bump output voltage a little ways past 13 or 14 volts if you’d like to use them for certain battery charging tasks.

Sure, you’re not getting a variable power supply, but if you need 12 volts and lots of it, this is a great way to go. We’ve featured similar builds before, too, turning ATX PC power supplies into useful benchtop tools.

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Hackaday Links: April 19, 2026

April 19, 2026 by 3 Comments

We’ll start things off this week with a story that’s developing more than 25 billion kilometers from Earth — on Friday, NASA announced that the command had been sent to shut down Voyager 1’s Low-energy Charged Particles (LECP) instrument. As the power produced by the spacecraft’s aging radioisotope thermoelectric generator (RTG) continues to dwindle, engineers at the Jet Propulsion Laboratory have been systematically turning off various systems to extend the mission for as long as possible. It’s believed that deactivating LECP should buy them another year, during which engineers hope to implement a more ambitious power-saving routine. If this sounds a bit familiar, you’re probably thinking of Voyager 2. The plug was pulled on its LECP instrument back in March of 2025.

The JPL engineers hope that their new plan may allow them to reactivate previously disabled systems on the twin space probes, but even if everything goes according to plan, there’s no fighting the inevitable. At some point, there simply won’t be enough juice in the RTGs to keep the lights on. Although it’s going to be a sad day when we have to bring you that news, surviving a half-century in space is one hell of a run.

Speaking of ending a run, just a week after Amazon announced that pre-2012 Kindles would no longer be supported, the company is letting users know that the Kindle software for PCs will be discontinued in June. In its current form, at least. As Good e-Reader reports, Amazon is developing a new client for users who want to access the Kindle ecosystem from their computers, but it will only run on Windows 11. Since older software could be used to strip DRM from purchased ebooks, it seems likely this is another attempt to lock the platform down.

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2026 Green Powered Challenge: The Eternal Headphones

April 19, 2026 by 22 Comments

Noise cancelling headphones are a great way to insulate yourself from the bustle of the city, but due to their power requirements, continuous use means frequent recharging. [Alessandro Sgarzi] has an elegant and unique solution — powering the noise cancelling electronics by harvesting energy from the ambient noise of the city via a sheet of piezoelectric film.

This impressive feat is achieved using a LTC3588-1 power harvesting IC and a pair of supercapacitors, while an STM32L011K4T6 microcontroller processes the input from a MEMS microphone and feeds a low-power class D amplifier. This circuit consumes an astounding 1.7 nW, a power that a noisy city is amply able to supply. Audio meanwhile comes via a traditional 3.5 mm connector, which we are told is the cool kids’ choice nowadays anyway.

We like this project, and since it’s part of our 2026 Green Powered Challenge, it’s very much in the spirit of the thing. You’ve just got time to get your own entry in, so get a move on!

2026 Hackaday Greep Powered Challenge

Rack Cage Generator Gets Your Gear Mounted

April 19, 2026 by 22 Comments

Sometimes, as hackers and makers, we can end up with messy lashed-together gear that is neither reliable nor tidy. Rackmounting your stuff can be a great way to improve the robustness and liveability of your setup. If you find this appealing, you might like CageMaker by [WebMaka].

This parametric OpenSCAD script can generate mounts for all kinds of stuff. Maybe you have a little network switch that’s just a tangle of wires on your desk, or a few pieces of audio gear that are loosely stacked on top of each other and looking rather unkempt. It would be trivial with this tool to create some 3D printed adapters to get all that stuff laced up nice and neat in a rack instead.

If you’re eager to get tinkering, you can try out the browser-based version quite easily. We’ve featured similar work before, too—many a maker has trod the path of rackmounting, as it turns out.

A hexagonal brass enclosure surrounds an aluminium fan with three blades. The fan has an integrated outer rim with a series of small holes around the rim.

Building A Rim-Driven Jet Engine

April 19, 2026 by 17 Comments

Rim-driven thrusters turn the normal propeller-motor arrangement inside out; rather than mounting the motor at the center of the propeller, they use a large hollow motor, with the blades attached to the inside of the rotor. They’re mostly used in ship propellers, though there have been some suggestions to use them in electric aircraft. [Integza], always looking for new and unusual ways to create propulsion, took this idea and made it into a jet engine.

Rather than using an electric motor, the fan in this design is propelled by miniature rocket nozzles along the edge. The fan levitates on a layer of high-pressure gas between the fan rim and the housing. To prevent too much pressurized gas from escaping, the fan and housing needed to fit together closely, but with minimal friction. A prototype made out of acrylic and resin and powered by compressed air proved that the idea worked, but [Integza] wanted to make to this a combustion-powered engine.

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DIY UPS Keeps Home Assistant Running

April 19, 2026 by 25 Comments

If you put a bunch of computers in charge of your house, it’s generally desirable to ensure their up-time is as close to 100% as possible. An uninterruptible power supply can help in this regard. To that end, that’s why [Bill Collis] whipped one up for his Home Assistant setup.

[Bill]’s UPS is charged with one job—keeping the Home Assistant Green hub and an Xfinity XB7 cable modem online when the grid goes dark. The construction is relatively straightforward. When the grid is up, everything is powered via a Mean Well AC-DC 12 V power supply, while the power is also used to charge a 12.8 V 10 Ah lithium iron phosphate battery pack. When the grid goes out, the system switches over to running the attached hardware on pure battery power. A Victron BatteryProtect is used to automatically disconnect the load if the battery voltage drops too low. Meanwhile, a Shelly Plus Uni module is used to monitor battery voltage and system status, integrated right into Home Assistant itself.

If you want to keep the basics of your smart home going at all times, something like this is a pretty simple way to go.  We’ve featured some other great UPS builds in the past, too. If you’re whipping up your own hardware to keep your home or lab alive in the dark of night, don’t hesitate to notify the tipsline.