Author: Lewin Day

3447 Articles

Building A Wall-Mounted Sound Visualizer

December 27, 2025 by 7 Comments

Visualizers used to be very much in vogue, something you’d gasp in at amazement when you’d fire up Winamp or Windows Media Player. They’re largely absent from our modern lives, but [Arnov Sharma] is bringing them back. After all, who doesn’t want a cool visualizer hanging on the wall in their living room?

The build is based around the Raspberry Pi Pico 2. It’s paired with a small microphone hooked up to a MAX9814 chip, which amplifies the signal and offers automatic gain control to boot. This is a particularly useful feature, which allows the microphone to pick up very soft and very loud sounds without the output clipping. The Pi Pico 2 picks up the signals from the mic, and then displays the waveforms on a 64 x 32 HUB75 RGB matrix. It’s a typical scope-type display, which allows one to visualize the sound waves quite easily. [Arnov] demonstrates this by playing tones on a guitar, and it’s easy to see the corresponding waveforms playing out on the LED screen.

It’s a fun project, and it’s wrapped up in a slick 3D printed housing. This turns the visualizer into a nice responsive piece of wall art that would suit any hacker’s decor. We’ve featured some other great visualizers before, too. Continue reading “Building A Wall-Mounted Sound Visualizer” →

3D Printed PC Case Focuses On Ease Of Access

December 26, 2025 by 24 Comments

There are all kinds of fun, glowing PC cases on the market these days. However, if you want something that focuses on serviceability over flash while still looking stylish, you might like the Makeyo MK01. It’s a PC case that you can print yourself, and [Marst_art] has published a video on what it’s like to whip one up at home.

The MK01 is assembled from lots of smaller parts, so the components can be made on any 3D printer that has a print area of 210 x 210 mm or more. All the outer panels are affixed to the main chassis with magnets, which makes servicing easy. You can just pop off panels when you need to get inside without undoing any fasteners or clips.

Plus, the cool thing about the MK01 is that since you’re printing it yourself, you can easily make whatever mods you like prior to printing it out. [Marst_art] notes that he threw in a USB-C port to the front panel for easy access, and a few internal mounts for 2.5″ SSDs. He also made some mods to the power switch assembly. It also bears noting—you get to choose your own color scheme when you make one of these. This level of customization is something you simply don’t get when you buy off the shelf!

[Marst_art]’s video is a useful guide if you’re planning to undertake such a build yourself. It outlines what it’s like to actually print one of these things on a consumer printer, and how the settings will influence the final look and feel. It’s worth noting that you’ll probably want to print this in ABS or another filament that can handle high heat, unless you’re building a very cool running machine.

It’s not just a great looking case, it’s a highly functional one, too. Files are available on Printables if you’d like to make your own. We’ve featured other printed cases before, too.

Continue reading “3D Printed PC Case Focuses On Ease Of Access” →

MQTT Pager Build Is Bringing Beepers Back

December 25, 2025 by 20 Comments

Pagers were once a great way to get a message to someone out in public; they just had to be cool enough to have one. These days, they’re mostly the preserve of doctors and a few other niche operators. [Kyle Tryon] is bringing the beeper back, though, with a custom ESP32-based build.

The ESP32 is a great microcontroller for this kind of project, because it’s got WiFi and Bluetooth connectivity built right in. This let [Kyle] write some straightforward code so that it could receive alerts via MQTT. In particular, it’s set up to go off whenever there’s an app or service notification fired off by the Sentry platform. For [Kyle]’s line of work, it’s effectively an on-call beeper that calls them in when a system needs immediate attention. When it goes off, it plays the ringtone of your choice—with [Kyle] making it capable of playing tunes in Nokia’s old-school RTTTL music format.

The code was simple enough, and the assembly wasn’t much harder. By starting with an Adafruit ESP32 Reverse TFT Feather, the screen and buttons were all ready to go right out of the box. [Kyle] merely had to print up a rad translucent case on a resin printer to make it look like a sweet fashionable beeper from the 90s.

It’s a fun little project that should prove useful, while also being nicely reminiscent of a technology that has largely fallen by the wayside. Continue reading “MQTT Pager Build Is Bringing Beepers Back” →

Building A High-Performance Shifter For Sim Racing

December 25, 2025 by 10 Comments

These days, sim racing is more realistic than ever. There are better screens, better headsets, and better steering wheels with better force-feedback, all of which help make you feel like you’re driving the real thing. If you’re looking for a stick shifter to complete such a setup, [DAZ Projects] might have just what you’re looking for. 

To create a robust shifter with great feel, the build relies on 3D printed parts as well as lots of quality metal hardware. At the heart of the build is a linear rail for the front-to-back movement, with a printed slider on top with a carefully-profiled indexer to ensure the stick properly ca-chunks into the right gear. A ball joint locates the shift lever itself, while allowing for smooth movement left-to-right. Centering is via simple extension springs. The H-pattern shift is enforced with machined steel rods. Detecting the position of the stick is handled via microswitches, with an Arduino Leonardo reading the switches and reporting itself as a USB device that should work with any modern sim.

It’s funny to think that such a mechanism would once have been a very serious machining job. These days, you can just squirt all this stuff out on a printer in a few hours. For the parts that can’t be extruded, [DAZ Projects] has provided a parts list on Google Docs.

We’ve featured some great racing sim builds over the years, from button pads to pedal boxes.

Continue reading “Building A High-Performance Shifter For Sim Racing” →

Mesh “Lens” Lets Your Camera Make Weird Pixel Art

December 24, 2025 by 14 Comments

We seldom talk about 3D printing lenses because most techniques can’t possibly produce transparent parts of optical quality. However, you can 3D print something like a lens, as [Luke Edwin] demonstrates, and get all kinds of crazy pictures out of it. 

[Luke’s] lens isn’t really a lens, per se. There’s no transparent optical medium being used to bend light, here. Instead, he’s printed a very fine grid in a cylindrical form factor, stuck it on a lens mount, and put that on the front of a camera.

The result is effectively a set of parallel tubes that guide light on to the camera’s image sensor. With the lack of any sort of focus mechanism, you can’t use this “lens” to photograph anything more than a few centimeters away. Get something up close, though, and you can take very simple, very grainy images that are reminiscent of classic pixel art. [Luke] demonstrates this in some fun ways, using it to take photographs of money, a plant, and his own eye. The images look almost like art assets straight out of a 16-bit game. He’s got the STL file up for sale if you want to print your own at home.

We’d love to see this concept explored further, maybe with some supporting optics for more versatile use. In the meantime, you might explore other ways of using 3D printers for photographic gain.

Continue reading “Mesh “Lens” Lets Your Camera Make Weird Pixel Art” →

Disposable Camera Viewfinder Becomes 3D Printed Lens

December 24, 2025 by 10 Comments

Disposable cameras are a fun way to get into classical photography. However, they can also be a valuable source of interesting parts that can be put to other uses. For example, as [Billt] demonstrates, their viewfinders can be repurposed into a rather interesting lens for more serious cameras.

[Billt] was lucky enough to score a grabbag of used disposable cameras from a local film lab, and tore them down for parts. He was particularly interested in the viewfinders, since Kodak equipped its disposable cameras with actual plastic lenses for this very purpose.

[Billt] wanted to see what these lenses would do when thrown on the front of a proper digital camera, and set about designing a mount for that purpose. The 3D printed part was designed to mount one of the viewfinder lens assemblies on the front of any Sony E-mount camera. In a rather nifty trick, [Billt] realized the lens assembly could be installed in the adapter by pausing mid-way through the 3D print to drop it in. The only unfortunate thing? The lenses didn’t really work, and all the camera could see was a haze of unfocused light.

With the aid of some cardboard experiments, [Billt] decided to make some changes. The front element of the viewfinder was dumped, with the rear element being used solo instead. This was fitted to the adapter on a simple slide mechanism so that focus could be reliably adjusted. With these changes, the lens came good, and provided some really interesting shots. It’s quite a cropped lens and it can achieve a very close focus distance, as little as 1 inch in testing. It’s quite sharp in the center of the image, while softly blurring out towards the edges—something that sounds very familiar if you’ve used one of these disposable cameras in the wild.

Sometimes it’s fun to grab a random piece of junk to see if you can turn it into something good. Video after the break.

Continue reading “Disposable Camera Viewfinder Becomes 3D Printed Lens” →

DIY E-Reader Folds Open Like A Book

December 24, 2025 by 36 Comments

There are plenty of lovely e-readers out on the market that come with an nice big e-paper display. There aren’t nearly as many that come with two. [Martin den Hoed] developed the Diptyx e-reader with such a design in order to better replicate the paper books of old. 

The build is based around the ESP32-S3, a powerful microcontroller which comes with the benefit of having WiFi connectivity baked in. It’s hooked up to a pair of 648×480 e-paper displays, which are installed in a fold-open housing to create the impression that one is reading a traditional book. The displays themselves are driven with custom look-up tables to allow for low-latency updates when turning pages. The firmware of the device is inspired by the epub reader from [Atomic14], and can handle different fonts and line spacing without issue. Power is from a pair of 1,500 mAh lithium-polymer cells, which should keep the device running for a good long time, and they can be charged over USB-C like any  modern gadget.

You can follow along with the project on the official website, or check it out on Crowd Supply if you’re so inclined. The project is intended to be open source, with files to be released once the design is finalized for an initial production run.

We’ve seen some great DIY e-reader builds over the years, and we’re loving the development we’re seeing in the writer deck space, too. If you’re whipping up something fun in this vein, be sure to let us know on the tipsline!