Ryze Blog

A 3D-Printed Watch Case With a Bayonet-Mount Back

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Maker Z0hn set out to 3D print an entire watch case from scratch, and solved the one detail that trips up most printed-case builds: how to close the back.

What They Built

The project is a complete watch case, printable on an ordinary FDM machine, designed to hold a standard off-the-shelf Miyota 8N24 movement and a stock crystal. Rather than a high-end custom movement, the interesting part is entirely in the case design itself.

How They Did It

Printed threads and screw-down backs are notoriously unreliable on FDM printers — layer lines and dimensional tolerances make fine threads gritty or loose, and they tend to strip out over repeated opening and closing. Z0hn's case sidesteps the problem with a bayonet-style twist-lock back instead: a quarter-turn connector that's far more forgiving to print accurately and holds up better to daily handling than threaded alternatives. The rest of the design is built to be easy to modify, with details like crown placement left open for makers to adapt to their own movement or wrist preferences.

Go See It

Z0hn published the full build on Instructables as "Building Your Own Custom Watch From Scratch," a step-by-step guide covering the case design and assembly. Hackaday featured the project on June 13, 2026.

This Watch Tells Time With A Single Needle On An Analog Meter

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Most watch displays — digital or e-ink or even classic analog hands — are built to show multiple things at once: hours, minutes, sometimes seconds. Sahko's watch flips that assumption, using a single sweeping needle borrowed from an analog panel meter to display one value at a time.

What They Built

The watch is built around a simple analog coil meter, the kind normally used to show voltage or current on a piece of test equipment, repurposed here as a time display. A Raspberry Pi Pico drives the meter through a digital-to-analog converter, sweeping the needle to whatever position corresponds to the current hour, minute/second, month, or day of the week — selected by pressing buttons on the case.

How They Did It

Two details push this past a quick proof of concept. The dial backer isn't printed paper, it's a custom PCB, giving it a far more durable, professional finish than the usual paper-and-laminate approach. And the case itself is CNC-milled out of aluminum and bead-blasted for a clean industrial surface finish — the kind of fit and finish that makes a one-off build feel closer to a manufactured instrument.

Why It's Worth Your Time

Trading a multi-hand or digital display for a single needle is a real design compromise — you genuinely can't see two values at once — but it produces an instrument-panel aesthetic that nothing else in this roundup has, and it's a clean example of a watch project where the dial mechanism itself is the hack, not just the electronics behind it.

Go See It

Sahko's build is documented on GitHub, and Hackaday covered the project with photos and a demo video.

ChronoWatch X2040 Is A Clean, Reproducible RP2040 Round-Display Watch

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Not every DIY watch needs to push a new idea to be worth a look — sometimes the value is in how cleanly a familiar formula gets executed. ChronoWatch X2040, built by Vishalsoniindia, is a round-display RP2040 watch done with enough documentation that someone else could realistically build their own copy.

What They Built

The watch is built around a Waveshare RP2040 Round 1.28-inch touch display, housed in a three-part case designed in Tinkercad and 3D printed in ABS. It includes multiple selectable watch faces, adjustable 12/24-hour time and date settings, brightness control, a stopwatch, and a sleep-timer mode for battery management — all controlled entirely through the touchscreen, with no companion app or phone pairing required.

How They Did It

The case design splits sensibly into a body section that holds the display, battery, and strap mounts, a locking front ring that keeps the display seated, and a screwed-on back for serviceability. Heat-set inserts give the printed plastic real metal threads to screw into, and an Apple Watch strap handles the wrist fit rather than a custom-designed band — a practical shortcut that saves a fair amount of design time without hurting the final result.

Why It's Worth Your Time

It's a solid "build this yourself" entry point into round-display RP2040 watches: less novel than some of the other projects we've covered, but the firmware, schematics, and 3D files are all published and the build steps are genuinely followable.

Go See It

Vishalsoniindia's full writeup, code, and design files are on Hackster.io, with source on GitHub.

DRM Watch 3 Is Built To Actually Be Worn Every Day

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

A lot of DIY smartwatch projects are built to demo well — a working prototype shown off in a video, with no real intention of strapping it on and wearing it through a normal week. DRM Watch 3, from developer drfailov, is explicitly built for the opposite goal.

What They Built

The watch is built around an ESP32-S2 paired with a 2.7-inch Sharp Memory LCD, a low-power reflective display technology that behaves a lot like e-paper without the slow refresh. A 450mAh battery gets the watch to roughly two weeks of runtime per charge, and the interface ships with a bilingual English/Ukrainian UI. Total parts cost lands around $70.

How They Did It

The build leans into details that matter for daily wear rather than a one-off demo: a custom-cut electroluminescent panel handles backlighting without washing out the Sharp LCD's main power advantage, and the enclosure is designed to be either 3D printed or CNC-machined from metal, depending on how durable you want the final case to be. None of that is flashy, but it's exactly the stuff that decides whether a DIY watch survives contact with real life.

Why It's Worth Your Time

"Suitable for daily use" is the operative phrase in the project's own framing — it's a useful reminder that battery life and case durability are often the harder engineering problems in a smartwatch build, not the display or the firmware features.

Go See It

drfailov's full source and design files are on GitHub, with project background also posted to Hackster.

This Pip-Boy Smartwatch Is Built From Brass and Copper Pipe

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Fallout's Pip-Boy has inspired more wrist-worn builds than just about any other piece of fictional hardware, but most of them lean on 3D-printed shells. Huy Vector went a different route, building a Pip-Boy-style smartwatch out of plumbing parts.

What They Built

The watch runs on a Xiao ESP32-S3 board driving a 1.54-inch LCD that recreates the Pip-Boy's characteristic green-on-black interface, with a MAX30102 sensor added on for heart rate readings. It's a recognizable, functional take on the franchise's signature device, scaled down to fit a wrist instead of a forearm.

How They Did It

The standout decision here is the housing: rather than printing a plastic case, Huy Vector built the watch's body from copper tubing and brass hardware. That metal isn't just for looks — sections of it double as capacitive touch points, so the watch's controls are wired directly into the same material that forms its shell. A leather strap finishes the look, giving the whole thing the feel of a piece of dressed-up industrial hardware rather than a 3D print with a screen bolted on.

Why It's Worth Your Time

It's worth comparing this against Arnov Sharma's PIP-WATCH v2, also covered here — same source material, but a completely different build language. Where Sharma's build leans on an unusual wide touch display to nail the aesthetic in software, Huy Vector gets there through material choice, using copper and brass as both structure and input hardware. Two valid paths to the same wrist computer.

Go See It

Huy Vector's build was covered by Hackaday, with photos and video of the brass-and-copper housing in action.

Glowtape Is A Watch You Read By Pulling Tape Out Of It

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Every display technology on a DIY watch eventually starts to look familiar — e-ink, OLED, LED matrices, the occasional e-paper panel. Henner Zeller's Glowtape, spotted at Supercon 2024, isn't any of those. It tells time by writing onto a physical strip of glow-in-the-dark tape as it's pulled out of the watch.

What They Built

Glowtape uses a dense UV LED array to charge a roughly two-inch-wide strip of phosphorescent tape as it scrolls past, leaving a glowing afterimage that briefly displays the time, date, or — since the system can write arbitrary patterns — images and longer strings of text as a scrolling banner.

How They Did It

Zeller released the complete source for the project: OpenSCAD files for the 3D-printed housing that the tape and LED array sit inside, plus the C firmware running on an RP2040 that controls the UV array timing to "write" onto the tape as it moves. The tricky part isn't really the electronics — it's getting the LED charge timing and tape speed to line up so the glow forms legible characters rather than a smear.

Why It's Worth Your Time

It's impractical in basically every sense that matters for a watch — the glow fades within seconds, and you're trailing a foot of tape off your wrist to read the time — but that's exactly the kind of "why not" build that belongs on a site about hacker watches instead of commercial ones. Nobody is shipping this as a product; that's the point.

Go See It

Henner Zeller's source files are on GitHub, and Hackaday covered the project after spotting it at Supercon 2024.

A Homemade ESP32 Smartwatch, Built So It Can't Spy On Anyone

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Shopping for a commercial smartwatch usually means comparing specs and reading reviews. Reddit user CoreMemory_156 skipped that step entirely and built a smartwatch from the ground up — partly for the challenge, and partly because a device you built yourself can't quietly phone home with your data.

What They Built

The watch is built around an ESP32-WROOM-32D microcontroller on a homemade PCB, wired to a 240x280 LCD display, an accelerometer, a heart rate sensor, a real-time clock module, a vibration motor, and a speaker, all running off a 200mAh rechargeable battery in what appears to be a 3D-printed case on a wrist strap. It's an oversized watch by commercial standards, but it covers a genuinely complete feature set for a first build.

How They Did It

Beyond the hardware basics, CoreMemory_156 has implemented several clock face styles, custom wallpaper support, a heart rate monitor app, a Tetris clone, a timer, a flashlight, and — for testing on the family dog, presumably — an ultrasonic blaster. Planned additions include a Pong clone, a temperature sensor, an ambient light sensor for automatic screen dimming, Bluetooth music control, and gyroscope-based games.

Why It's Worth Your Time

There's no formal build guide yet, but the bill of materials and photos shared in the original Reddit post give enough to work from if you want to attempt something similar — and the privacy angle is a different hook than most DIY smartwatch writeups, which tend to lead with hardware bragging rights rather than why you'd want to own your own data trail.

Go See It

Hackster covered CoreMemory_156's build, crediting and linking the original Reddit post with the bill of materials and photos.

A Drop-In Open-Source Brain for the Casio G-Shock

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

David Volovskiy's "Jolt" project swaps the brain of a $20 Casio G-Shock for one you can actually program, without touching the case, display, or buttons that make the watch what it is.

What They Built

Jolt is a replacement circuit board sized to drop straight into a Casio DW-5600 series G-Shock in place of the stock quartz module. Once installed, the watch keeps its familiar segmented LCD and buttons, but everything behind them is now open hardware running open firmware — meaning anyone can flash their own watch faces, tools, or games onto a case that used to just tell the time.

How They Did It

Jolt builds on the firmware lineage started by Joey Castillo's Sensor Watch and Movement projects, which did something similar for the Casio F-91W. Volovskiy forked that codebase and added board support for the G-Shock's different LCD segment layout, then went further by building a browser-based firmware emulator and an LCD-segment "playground" tool, so a new watch face can be designed and tested before it ever touches real hardware. The project has matured to a tagged 2.0.0 release with a real catalog of faces beyond basic clock/stopwatch/alarm functions, including a blackjack game, a Wordle clone, an endless runner, Simon, and a tarot card face — the kind of feature list you'd expect from a hobby OS, not a watch.

Why It's Worth Your Time

Most "hacked watch" projects work around stock hardware. This one replaces it outright while keeping the part people actually care about — the case and display — fully intact, which is a cleaner way to turn cheap, ubiquitous hardware into a real development platform.

Go See It

David Volovskiy documented the project on GitHub at voloved/second-movement, an MIT-licensed fork of joeycastillo/second-movement; the repo has full build instructions, release notes, and the watch face source. Hackaday covered the project on June 23, 2026, with additional background on how it fits into the broader Sensor Watch ecosystem.

LightInk Is A Solar-Powered Smartwatch That (Almost) Never Needs Charging

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Daniel Ansorregui's LightInk takes the e-ink-plus-ESP32 smartwatch formula popularized by Watchy and adds a built-in solar panel, then squeezes out enough extra power efficiency to make that panel actually meaningful.

What They Built

LightInk is a wrist-worn smartwatch built around an ESP32-PICO and a 1.54-inch e-paper display, with WiFi, Bluetooth, LoRa, and GPS on tap and a small solar cell built into the face. It runs on a 100mAh battery, but thanks to the solar assist and aggressive power management, it's designed to go roughly 9 to 10 months between charges under normal use.

How They Did It

E-ink already does most of the power-saving work just by only drawing current during a screen update, but Ansorregui found that booting the ESP32 itself was eating a surprising share of the budget: a normal cold boot takes about 28 milliseconds and burns roughly a milliamp-second of charge, mostly just copying code from flash into RAM before any useful work happens. His fix was to skip that step entirely for routine wake-ups, using the ESP32's RTC memory — a small pool of memory the chip can execute from in microseconds, without touching flash at all. By reimplementing the SPI display driver to run from RTC memory, the watch can wake, push an update to the screen, and go back to sleep in under a millisecond of active time, cutting overall power use roughly in half. The pricier radios — LoRa and GPS in particular — are treated as occasional-use features rather than always-on, since they're where the remaining power budget actually goes.

Why It's Worth Your Time

The RTC-memory wake-stub trick isn't specific to watches — it's a general pattern for any battery-powered ESP32 project where the bulk of your power draw is wasted on boot overhead rather than the actual work being done.

Go See It

Daniel Ansorregui's full hardware and firmware files are on GitHub, including the ESP-IDF source, EasyEDA design files, and 3D-printable case models. Hackaday covered the project on May 5, 2026, and a demo video on the project page shows the watch's full feature set in action.

Making A Mechanical Watch Movement From Scratch, Right Down To The Pinions

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Most of the watches we cover here lean on a microcontroller and a display. John Raffaelli's project is the opposite extreme: no firmware, no electronics, just a fully hand-machined mechanical watch movement built on his own machine tools.

What They Built

Raffaelli set out to build a working mechanical watch movement from raw stock, limiting his bought parts to the handful of things that are genuinely impractical to make at home: jewels, the sapphire crystal, the strap, the hairspring, and the mainspring. Everything else — gear trains, pinions, the balance wheel, plates and bridges — he cut himself, at a scale where features are smaller than a fingertip and tolerances leave essentially no room for error.

How They Did It

This is precision machining at the limit of what a home shop can manage: parts this small require careful work holding, sharp tooling, and a willingness to scrap a piece and start over when a cut goes even slightly wrong. There's no firmware to patch a mistake after the fact — a pinion cut a few microns off either works or it doesn't.

Why It's Worth Your Time

It's a useful counterweight to a batch of builds otherwise dominated by ESP32 boards and touchscreens: a reminder that "build your own watch" can mean building the actual mechanism that keeps time, not just the case and display around someone else's movement.

Go See It

Hackaday's writeup on John Raffaelli's movement has more detail and photos of the machining process.

Reverse-Engineering the Mi Band 10's Unreleased Chip — Then Running DOOM On It

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Xiaomi never released an SDK for the chip inside the Mi Band 10, so Aaron Christophel built one anyway, then used it to run DOOM on a fitness tracker.

What They Built

The Mi Band 10 runs on a Bestechnic BES2700iMP/BEST1503 chip with no public documentation or development tools. Christophel reverse-engineered enough of it to write working custom firmware from scratch, and demonstrated the result by porting DOOM to run on the band's own AMOLED screen, controlled by its own touch panel.

How They Did It

The starting point was a leaked SDK for a related Bestechnic audio chip, the BES2700IHC/BEST1306, plus a separately leaked flashing tool that included the secondary-stage bootloader blobs needed to actually talk to the hardware. By cross-referencing that SDK against the Mi Band 10's stock firmware byte by byte, Christophel mapped out the real memory layout — which turned out to be larger than documented, 1.4MB of SRAM and 4MB of flash versus the audio SDK's stated 512KB and 2MB — along with the display and touch subsystems: a Raydium RM690B0/C0 AMOLED panel driven over QSPI, and a Hynitron CST92xx touch controller on I2C. From there, getting DOOM running meant porting GBADoom with a custom hardware glue layer, dithering the output down to RGB332 for the display, and mapping touch zones to game controls. A Python-based UART flasher built around the recovered bootloader handles getting firmware onto the device.

Why It's Worth Your Time

This isn't reverse engineering for its own sake — it's a fully documented, from-nothing SDK for a chip that had none, written up clearly enough that someone else could follow the same trail on a different Bestechnic part.

Go See It

Aaron Christophel (atc1441) documented the full process on GitHub, where the README walks through the memory map, display and touch findings, the DOOM port, and the flashing process in detail. Hackaday covered the project on June 21, 2026.

OM10 Is The First Fully Open-Source Mechanical Watch Movement

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Mechanical watch movements are normally one of two things: proprietary designs locked up by the manufacturer, or reverse-engineered guesswork pieced together from forum threads and teardown photos. The Openmovement foundation's OM10 is neither — it's a movement designed from a blank sheet specifically to be given away.

What They Built

OM10 is a fully open-source mechanical watch movement running a Swiss pallet escapement at 3.5Hz, or 25,200 vibrations per hour — solidly in line with what you'd expect from a mainstream automatic or hand-wound caliber. It's built around modularity and serviceability rather than maximum thinness or jewel count, which fits its intended audience: people learning to work on movements, not just admire them.

How They Did It

The foundation released complete STEP files covering the entire movement, available to anyone who creates a free account to download them. That's a meaningfully different posture than most watchmaking IP, which tends to stay locked inside Swiss manufacture walls even when a movement is decades old. Releasing manufacturable CAD data — not just photos or a parts list — means a school, a hobbyist machinist, or another open-hardware project can actually produce or modify the thing, not just look at it.

Why It's Worth Your Time

A from-scratch open mechanical movement is rare enough that it's worth flagging on its own, independent of any specific watch built around it — this is infrastructure for the next generation of DIY mechanical watch projects, not a one-off build.

Go See It

Read more about OM10 via Hackaday's coverage of the Openmovement foundation's release.

OpenWear C3 Is a Smartwatch Platform Built From Bare PCB Up

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Most DIY smartwatch projects start from a development board and work backward. Hansel Kay's OpenWear C3 starts from a blank PCB layout and builds the whole platform up from there.

What They Built

OpenWear C3 is an open smartwatch platform centered on an ESP32-C3, with a custom PCB handling power regulation, sensor wiring, and display control rather than relying on an off-the-shelf dev board crammed into a case. Running on a 600mAh battery, it lasts roughly two to four days per charge depending on how features like raise-to-wake are configured.

How They Did It

The board was laid out in EasyEDA and fabbed through standard PCB houses like JLCPCB or PCBWay, with a voltage converter stepping input power down to a clean 3.3V rail for the microcontroller and sensors, plus the supporting passives for I2C pull-ups, battery voltage sensing, and backlight control. The design supports a MAX30100 heart-rate sensor, with the option to swap in a MAX30102 at the cost of some register-level firmware changes. On the software side, a good chunk of effort went into display handling specifically — tuning the wake and UI transition routines to cut down on the flickering and ghosting that's a common annoyance on small embedded displays.

Go See It

Hansel Kay (hanselkay8) documented the full PCB design and firmware on Hackster.io under the project name "OpenWear C3," including schematic and firmware details for anyone looking to build their own.

This Pebble-Inspired Smartwatch Is On Its Fifth PCB Revision

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

The Pebble was, for a while, the closest thing the smartwatch world had to a genuinely open, hackable platform — simple hardware, an easily programmable interface, and a community that actually built things for it. After it was acquired by Fitbit and effectively wound down, Matthew James Bellafaire set out to build something with the same spirit.

What They Built

The watch is built around an ESP32 in its WROOM module configuration, taking advantage of the chip's dual-core processor and simultaneous WiFi and Bluetooth support. Bellafaire's board, now on its fifth revision, includes onboard battery charging and power management, an ADXL337 accelerometer, an LCD controller, and a touch controller, with each module switched through its own MOSFET so unused subsystems can be powered down to save battery.

How They Did It

A custom Android app acts as the watch's bridge to the outside world, handling Bluetooth Low Energy notifications by streaming text to the watch in small chunks and terminating each message with a marker the firmware watches for. The watch can also control Spotify playback over Bluetooth, displaying the current track and exposing play/pause and skip controls, and the firmware itself is built to be modular enough that other developers can add their own features without redesigning the whole thing.

Why It's Worth Your Time

The fifth-revision PCB is the real story here — this isn't a single weekend prototype, it's a hardware platform that's been iterated on repeatedly in response to real use, which is a different kind of DIY smartwatch story than most one-off builds.

Go See It

Matthew James Bellafaire's design files and firmware are on GitHub, with additional background from Hackster.

Piko Is A Tamagotchi-Style Fitness Buddy On Your Wrist

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Fitness trackers tend to reduce activity to a number on a screen — steps, heart rate, calories. Piko, built by Iloke Alusala, Lulama Lingela, and Rafael Cardoso, takes a more playful approach: instead of a number, you get a little pixel-art character that visibly mimics what you're doing.

What They Built

Piko is a wrist-worn fitness tracker built around an ESP32 Beetle C6, a LIS331HH accelerometer, a 240x240 IPS TFT display, and a 200mAh battery. The accelerometer data drives a hand-drawn character on screen that shifts between idle, walking, jogging, and sprinting poses depending on how active you currently are — a Tamagotchi-style stand-in for your activity level rather than a plain stat readout.

How They Did It

The team 3D printed the watch's parts in their university makerspace and released the firmware under an MIT license, alongside a clear bill of materials. Translating raw accelerometer readings into a believable, non-jittery activity state for the character to react to is the kind of detail that's easy to get wrong — too sensitive and the character flails between states constantly, too sluggish and it stops feeling responsive.

Why It's Worth Your Time

The pixel-character framing is a genuinely fun UI choice layered on top of an otherwise fairly standard ESP32 fitness build, and because the code and parts list are both fully open, it's one of the more approachable projects in this batch for someone who wants to actually replicate it rather than just admire it.

Go See It

Piko's project page is on Hackaday.io, with additional coverage from Hackaday.

PIP-WATCH Version 2 Puts A Pip-Boy On A Wide-Screen Wrist Display

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Plenty of makers have built Pip-Boy-themed wearables, but most reach for a roughly square or round display. Arnov Sharma's PIP-WATCH Version 2 takes advantage of an oddball board instead: the Lilygo T-Display-S3 Long, with a 180x640 touch-enabled strip display that happens to suit Fallout's wrist computer aesthetic unusually well.

What They Built

PIP-WATCH v2 is an ESP32-based wrist wearable built around that long, narrow touchscreen, recreating the Pip-Boy look in a form factor that reads more like an actual wrist-mounted instrument panel than a typical round or square smartwatch face.

How They Did It

Sharma picked the T-Display-S3 Long specifically for its shape, then worked through the build despite documentation for the board itself being patchy in places — a common problem with newer, more niche ESP32 dev boards. The result is build notes detailed enough that someone following in his footsteps can skip a lot of the trial and error he had to do firsthand.

Why It's Worth Your Time

This pairs naturally with Huy Vector's brass-and-copper Pip-Boy build, also covered here: same source material, but Sharma gets there by choosing the right unconventional display hardware rather than leaning on housing materials, which is its own kind of hack — knowing which oddball board exists and that it'll fit the bill.

Go See It

Arnov Sharma's project page is on Hackaday.io, and Hackaday covered the build with additional photos.

This Smartwatch Has A Laser, A Jukebox, And A Coin Flipper

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Most DIY smartwatch builds chase the same handful of goals: fitness tracking, notification mirroring, maybe a custom watch face or two. ddominik's open-source build mostly skips that list in favor of features that exist purely because they're fun to have on your wrist.

What They Built

The watch is built around a Waveshare RP2040-Matrix board with a built-in 5x5 LED matrix, paired with an OLED display, a 5V boost converter, and a buzzer. On top of basic timekeeping, it packs a 5mW laser module with a roughly 3km nighttime range, NeoPixel matrix animations including a plasma effect and a countdown sequence, an 8-bit "jukebox" that plays retro game themes by manipulating PWM frequencies through the buzzer, a digital notepad for storing phone numbers, a temperature reading pulled from the RP2040's internal sensor, and a coin-flipper app for settling bets.

How They Did It

ddominik describes the build process candidly as a learning project, complete with a soldering mistake that let the magic smoke out of the voltage converter, fixed with some manual PCB grinding and a generous application of hot glue and duct tape. The result is a self-described "ultra-raw prototype" — fully working, but with the exposed solder joints and bulkier footprint that come with a first hardware pass.

Why It's Worth Your Time

It's a refreshing change of pace from the fitness-tracker-or-notification-hub formula most DIY smartwatches default to, and a good demonstration that a watch project's value doesn't have to come from practicality.

Go See It

ddominik's full project writeup is on Hackster.io, with source code on GitHub.

A Custom Smartwatch Built To Make Diabetes Monitoring Easier For A Kid

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Living with Type 1 diabetes means tracking blood glucose constantly, and for kids especially, the devices built to make that easier can become their own source of friction. Andrew Childs built a smartwatch for his nine-year-old son specifically to get that friction out of the way.

What They Built

The obvious commercial answer — an Apple Watch paired to a Dexcom continuous glucose monitor — works, but strapping an Apple Watch onto a nine-year-old's wrist is, in Childs's words, a recipe for disaster. His alternative is a custom-built watch around an ESP32-S3, with a 1.69-inch TFT IPS display, a LiPo battery, an accelerometer for activity monitoring, and a vibration motor for haptic feedback, all on a custom PCB.

How They Did It

The hardest part wasn't the display or the sensors — it was getting a stable Bluetooth Low Energy connection to his son's iPhone, since the watch needs that link to pull CGM data in real time. Past that hurdle, Childs had the case made by a local 3D printing company and sourced custom-cut, silkscreened glass for the face, landing on a result that looks notably more polished than a typical first hardware project.

Why It's Worth Your Time

It's a build with an obvious, personal reason to exist, and a good example of smartwatch hacking pointed at accessibility and daily quality of life rather than novelty or fitness vanity metrics. Childs hasn't open-sourced the project yet but has said he plans to.

Go See It

Andrew Childs wrote up the full build on his own site, and Hackaday covered the project.

Tick-Tach Is A DIY Timegrapher For Under $30

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Not every watch hack is a watch — some are tools for keeping the watches you already own running well. Tick-Tach, built by TallmanLabs (Rupert Hirst, going by the handle koogar), is a DIY timegrapher built for hobbyists who'd rather not pay commercial prices for a niche diagnostic tool.

What They Built

A timegrapher listens to a mechanical watch's ticking and turns it into three numbers that matter to anyone regulating a movement: rate (how many seconds it gains or loses per day), amplitude (how far the balance wheel swings, an indicator of the movement's available power), and beat error (how evenly spaced the tick and tock are). Tick-Tach gets there with a 30mm piezoelectric microphone instead of an expensive dedicated acoustic sensor, amplified through a transistor-based preamp.

How They Did It

The electronics live in a custom 3D-printed enclosure with a circular recess sized to seat a watch, a cavity for the piezo sensor, an integrated preamp board, and a headphone-style jack for output — plus a hair bobble built into the design to hold the watch in place while testing it in different positions. On the software side, it's compatible with existing open-source timegrapher tools: tg-timer and PC Timer Machine on desktop, and Watch Accuracy Meter on Android.

Why It's Worth Your Time

Commercial timegraphers can run into the hundreds of dollars, which puts real diagnostic capability out of reach for a lot of hobbyists and independent watch repairers. Tick-Tach lowers that barrier substantially while staying compatible with software people may already be using.

Go See It

TallmanLabs's design files are on GitHub, with the full project writeup on Hackaday.io.

WearPico Turns A Raspberry Pi Pico W Into A Full Smartwatch Platform

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

Most DIY smartwatch firmware projects start as a personal itch someone wants to scratch. WearPico started life as a university senior project at Yildiz Technical University's Department of Computer Engineering, built by Umut Sevdi as a serious look at what it takes to make a microcontroller behave like a real wearable platform.

What They Built

WearPico is open-source firmware, written as a bare-metal C program with no underlying operating system, that turns a Raspberry Pi Pico W — or any other RP2040-based board — into a working smartwatch. Beyond timekeeping, alarms, and a stopwatch, it adds fitness tracking, note-taking, and temperature measurement when built with the full reference hardware: a round touchscreen, accelerometer, buzzer, and vibration motor.

How They Did It

The smartwatch side handles the embedded fundamentals, but what makes this a platform rather than just a firmware demo is the companion Android app, also open source, which connects over Bluetooth to manage notifications, call handling, and media playback control as background services. The watch sends requests to the phone and the app responds, splitting the work sensibly between constrained hardware and a device that already has the compute and connectivity to spare.

Why It's Worth Your Time

Having the firmware, the Android app, and the 3D design files all released together — and all coming out of an academic project rather than a hobbyist's spare-time build — gives WearPico a more complete starting point than most single-repo smartwatch projects.

Go See It

Umut Sevdi's firmware is on GitHub, with the companion Android app in a separate repository, and Hackster covered the release.

Welcome to ChronoHackers

ChronoHackers — Fri, 26 Jun 2026 00:00:00 GMT

ChronoHackers is a showcase for interesting do-it-yourself watch projects from across the web. It works the way Hackaday does for electronics: someone, somewhere, builds something remarkable at their bench, and we find it, write it up, and send you to the source. One subject — watches — covered with genuine curiosity about how people make them.

It is not a shop and it is not a review site. There is nothing here to buy. Every post points outward to a real maker doing real work, with a short write-up to explain what they made and why it caught our eye.

Why This Exists

Most of the watch world online splits into two camps: places that sell you watches, and places that review the ones you can buy. Very little celebrates the people building them from scratch — the ones machining a movement, etching a custom PCB, or coaxing a sixty-year-old calibre back to life on a kitchen table. That work is scattered across Reddit threads, YouTube channels, GitHub repos, and maker forums, and it rarely finds a wider audience.

ChronoHackers exists to gather it in one place and give it the attention it deserves. It is for the making, not the buying.

What You Will Find Here

Projects span the full range of horological tinkering.

Mechanical builds. Movements assembled from kits or cut from raw stock, escapements, hand-finished bridges, and the occasional ambitious complication attempted in a home workshop.

Electronic and smartwatch builds. ESP32 and nRF wearables, e-ink and round-LCD faces, custom carrier boards, and open-source watch firmware.

3D-printed watches. Printable cases, dials, and components, and the small but growing scene of designers making wearable timepieces you can run off a printer at home.

Restorations and repairs. Dead movements brought back to life, full teardowns, and the diagnostic detective work that goes with them.

Tools of the trade. Winders, timing machines, jigs, and the homemade kit that makes everything else possible.

If it involves a watch and someone built, hacked, modified, or revived it, it belongs here. Polished product launches and unboxings do not.

How It Works

Every feature starts with a real project by a real maker. We discover them across the usual corners of the web, then write a short, original piece that explains what the project is and why it is worth a look. The aim is to give you enough to understand the idea and decide whether to dig in yourself.

Attribution is the rule, not a courtesy. We credit the maker by name and link straight to their original post, video, or repository every time. ChronoHackers is a signpost to good work, never a substitute for it. The goal is to send makers more readers, not to keep those readers to ourselves.

Who It Is For

People who own both a loupe and a soldering iron. Watch enthusiasts curious about what is possible beyond the catalogue, makers who have wandered into horology from electronics or 3D printing, and anyone who enjoys watching a clever build come together. No particular expertise is assumed, only an interest in how things are made and a willingness to be impressed by other people's ingenuity.

ChronoHackers is a love letter to the people building watches in sheds, spare rooms, and workshops — written for the people who want to join them. We find the projects, tell you why they matter, and hand you the link. The rest is up to you.