Category: how-to

Apple AirTags have speakers in them, and the speaker is not entirely under the owner’s control. [Shahram] shows how the speaker of an AirTag can be disabled while keeping the device watertight. Because AirTags are not intended to be opened or tampered with, doing so boils down to making a hole in just the right […]
Top of an RBMK at the Leningrad plant. Control panels of a pre-digitalization nuclear plant look quite daunting, with countless dials, buttons and switches that all make perfect sense to a trained operator, but seem as random as those of the original Enterprise bridge in Star Trek to the average person. This makes the reconstruction […]
Over on YouTube [Andrew Neal] has a Function Generator Build for Beginners. As beginner videos go this one is fairly comprehensive. [Andrew] shows us how to build a square-wave generator on a breadboard using a 555 timer, explaining how its internal flip-flop is controlled by added resistance and capacitance to become a relaxation oscillator. He […]
[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 […]
[GizmoThrill] shows off a design for an absolutely gorgeous, high-fidelity replica of the main character’s helmet from the video game Satisfactory. But the best part is the technique used to create the visor: just design around a cheap set of full-face “sunglasses” to completely avoid having to mold your own custom faceplate. One of the […]
Although jet engines are theoretically quite simple devices, in reality they tread a fine line between working as intended and vaporizing into a cloud of lethal shrapnel. The main reason for this is the high rotational speed of the rotors, with any imbalance due to poor manufacturing or damage leading to undesirable outcomes. It’s for […]
3D scanners rely on being able to identify physical features of an object, and line up what it saw a moment ago with what it sees now in order to build a 3D model. However, not every object is as distinct and visible as others at all angles, particularly in IR. One solution is reflective scanning […]
Although arguably redundant on a typical computer keyboard, the idea of embedding small screens into the buttons on devices like audio production gear that often have so many buttons can make a lot of sense. As exemplified by devices with a UX that regularly degrades into scrolling through options on a tiny screen. This was […]
What can one expect from 3D printing an 8″ Newtonian telescope? [Molly Wakeling] shares her thoughts after doing exactly that. The performance was on par with any solid 8″ telescope, but in the end it wasn’t really any cheaper than purchasing a manufactured unit. Does that mean it wasn’t worth it? Not at all! [Molly] […]
To make aerated concrete, add a foam-forming agent and stir in a significant amount of air. This serves to make the concrete significantly lighter, better insulating, and more resilient to fire. Making it can however be a bit of an issue, often requiring ingredients that aren’t purchased at the average DIY store. This is where […]