Making A DIY Refrigerated Vest With Battery And Solar Power

February 7, 2026 by 24 Comments

Keeping a cool head is difficult at the best of times, least of all when it’s summer and merely thinking of touching bare skin to the pavement already gets you a second-degree burn. Unfortunately, it’s not possible to spend all summer in an air-conditioned room, but what if you took said room with you? Introducing [Hyperspace Pirate]’s air-conditioned vest.

Following on from last time’s adventures with a battery-powered air-conditioner that merely blew cold air onto one’s overheating body, this time the same compressor is used for a more compact build.

Since obviously using your body as part of the condenser would be uncomfortable, instead a heat exchanger was used that transfers the delicious frosty cold to water-filled tubing, zip-tied inside a very fashionable vest.

The basic unit runs on a couple of LiPo packs, but a solar-powered circuit was also built and tested using two small-ish panels. Of course, the requisite backpack-sized setup for that configuration is somewhat bulky, but at least the panels can also provide shade in addition to power for the compressor, hitting two fiery birds with one frosty stone.

Compared to one of those solar-powered caps with a built-in fan, this unit with some refinement could actually be an improvement, as well as keeping you a lot chillier. We’re looking forward to [Hyperspace]’s trial runs in the upcoming Floridian summer, as well as future chilling adventures.

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Robots Talking To Robots

February 7, 2026 by 5 Comments

Although there are a few robots on the market that can make life a bit easier, plenty of them have closed-source software or smartphone apps required for control that may phone home and send any amount of data from the user’s LAN back to some unknown server. Many people will block off Internet access for these types of devices, if they buy them at all, but that can restrict the abilities of the robots in some situations. [Max]’s robot vacuum has this problem, but he was able to keep it offline while retaining its functionality by using an interesting approach.

Home Assistant, a popular open source home automation system, has a few options for voice commands, and can also be set up to transmit voice commands as well. This robotic vacuum can accept voice commands in lieu of commands from its proprietary smartphone app, so to bypass this [Max] set up a system of automations in Home Assistant that would command the robot over voice. His software is called jacadi and is built in Go, which uses text-to-speech to command the vacuum using a USB speaker, keeping it usable while still offline.

Integrating a voice-controlled appliance like this robotic vacuum cleaner allows things like scheduled cleanings and other commands to be sent to the vacuum even when [Max] isn’t home. There are still a few limitations though, largely that communication is only one way to the vacuum and the Home Assistant server can’t know when it’s finished or exactly when to send new commands to the device. But it’s still an excellent way to keep something like this offline without having to  rewrite its control software entirely.

He’s A Wrapper (Wire Wrapper, That Is)

February 7, 2026 by 23 Comments

Before PCBs, wiring electronic circuits was a major challenge in electronics production. A skilled person could make beautiful wire connections between terminal strips and components with a soldering iron, but it was labor-intensive and expensive. One answer that was very popular was wire wrapping, and [Sawdust & Circuits] shows off an old-fashioned wire wrap gun in the video below.

The idea was to use a spinning tool to tightly wrap solid wire on square pins. A proper wrap was a stable alternative to soldering. It required less skill, no heat, and was easy to unwrap (using a different tool) if you changed your mind. The tech started out as wiring telephone switchboards but quickly spread.

Not all tools were guns or electric. Some used a mechanical handle, and others were like pencils — you simply rotated them by hand. You could specify levels for sockets and terminals to get a certain pin length. A three-level pin could accept three wire wrap connections on a single pin, for example. There were also automated machines that could mass-produce wire-wrapped circuits.

The wire often had thin insulation, and tools usually had a slot made to strip the insulation on the tiny wires. Some guns created a “modified wrap” that left insulation at the top one or two wraps to relieve stress on the wire as it exited the post. If you can find the right tools, wires, and sockets, this is still a viable way to make circuits.

Want to know more about wire wrapping? Ask [Bil Herd].

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Why PlayStation Graphics Wobble, Flicker And Twitch

February 6, 2026 by 11 Comments

Although often tossed together into a singular ‘retro game’ aesthetic, the first game consoles that focused on 3D graphics like the Nintendo 64 and Sony PlayStation featured very distinct visuals that make these different systems easy to distinguish. Yet whereas the N64 mostly suffered from a small texture buffer, the PS’s weak graphics hardware necessitated compromises that led to the highly defining jittery and wobbly PlayStation graphics.

These weaknesses of the PlayStation and their results are explored by [LorD of Nerds] in a recent video. Make sure to toggle on subtitles if you do not speak German.

It could be argued that the PlayStation didn’t have a 3D graphics chip at all, just a video chip that could blit primitives and sprites to the framebuffer. This forced PS developers to draw 3D graphics without such niceties like a Z-buffer, putting a lot of extra work on the CPU.

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CIA’s World Factbook Is Gone

February 6, 2026 by 52 Comments

Before the Internet, there was a certain value to knowing how to find out about things. Reference librarians could help you locate specialized data like the Thomas Register, the EE and IC Masters for electronics, or even an encyclopedia or CRC handbook. But if you wanted up-to-date info on any country of the world, you’d often turn to the CIA. The originally classified document was what the CIA knew about every country in the world. Well, at least what they’d admit to knowing, anyway. But now, the Factbook is gone.

The publication started in 1962 as the classified “The National Basic Intelligence Factbook,” it went public in 1971 and became “The World Factbook” in the 1980s. While it is gone, you can rewind it, including a snapshot taken just before it went dark on Archive.org.

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Welding Nuts Inside Metal Tubes, Painlessly

February 6, 2026 by 26 Comments

[Jer Schmidt] needed a way to put a lot of M8 bolts into a piece of square steel tubing, but just drilling and tapping threads into the thin steel wouldn’t be strong enough. So he figured out a way to reliably weld nuts to the inside of the tube, and his technique works even if the tube is long and the inside isn’t accessible.

Two smaller holes on either side. Weld through the holes. A little grinding results in a smooth top surface.

Essentially, one drills a hole for the bolt, plus two smaller holes on either side. Then one welds the nut to the tubing through those small holes, in a sort of plug weld. A little grinding is all it takes to smooth out the surface, and one is left with a strong threaded hole in a thin-walled tube, using little more than hardware store fasteners.

The technique doesn’t require access to the inside of the tube for the welding part, although getting the nut back there in the first place does require a simple helper tool the nut can slot into. [Jer] makes one with some scrap wood and a table saw, just to show it doesn’t need to be anything fancy.

Another way to put a threaded hole into thin material is to use a rivnut, or rivet nut (sometimes also used to put durable threads into 3D prints) but welding a plain old nut to the inside was far more aligned with what [Jer] needed, and doesn’t rely on any specialty parts or tools.

[Jer]’s upcoming project requires a lot of bolts all the way down long tubing, which is what got him into all of this. Watch it in action in the video below, because [Jer] has definitely worked out the kinks, and he steps through a lot of tips and tricks to make the process painless.

Thanks [paulvdh] for the tip!

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Driving Sim Handbrake Based On Load Cell

February 6, 2026 by 2 Comments

Simulator-style video games are designed to scale in complexity, allowing players to engage at anything from a casual level to highly detailed, realistic simulation. Microsoft Flight Simulator, for example, can be played with a keyboard and mouse, a controller, or a huge, expensive simulator designed to replicate a specific airplane in every detail. Driving simulators are similar, and [CNCDan] has been hard at work on his DIY immersive driving sim rig, with this hand brake as his latest addition.

For this build, [CNCDan] is going with a lever-style handbrake which is common in motorsports like drifting and rallying. He has already built a set of custom pedals, so this design borrows heavily from them. That means that the sensor is a load cell, which takes input force from a lever connected to it with a spring mechanism. The signal is sent to an Arduino for processing, which is set up to send data over USB like any joystick or controller. In this case, he’s using an Arduino that was already handling inputs from his custom shifter, so he only needed to use another input and add some code to get his handbrake added into his sim.

[CNCDan] built a version of this out of laser-cut metal parts, but also has a fully 3D printable one available as well. Plenty of his other videos about his driving rig are available as well, from the pedal assembly we mentioned earlier to the force-feedback steering wheel. It’s an impressive set of hardware with a feel that replicates racing about as faithfully as a simulator could. Interestingly, we’ve also seen this process in reverse as well where a real car was used instead as a video game controller.

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