clock hacks

1015 Articles

The Most Intricate Of Freeform Digital Clocks

March 25, 2026 by 11 Comments

Digital clock projects have been with us since the 1970s, when affordable LEDs and integrated circuits became available. In 2026 most of them use a microcontroller, but for the AliExpress fans there’s one that goes straight back to the ’70s with a pile of logic chips. You can make it on the supplied PCBs, but that wasn’t for [ALTco]. Instead, he made the circuit in free form, using six metres of brass wire.

The construction is anchored together by a set of busbars that carry sockets for a set of seven-segment and driver modules. The circuit is typical for the day, with a crystal oscillator and divider chain feeding the counters for the displays. There are a few clever tricks that older engineers might recognize in order to reduce the chip count. In this case that’s negated by an extra set of circuitry allowing the time to be set from a rotary encoder.

We’re impressed by the intricacy of the device, made bit by bit without a plan, it as some wires what thread their way between others. It’s a truly beautiful piece, and it reminds us of our circuit sculpture contest back in 2020.

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3D Printed Clock Just Taps It In

March 21, 2026 by 4 Comments

The famous cuckoo clock, with its moving, chirping mechanical bird indicating various divisions of time, has been around since at least the 1600s. The most famous of them come from the Black Forest area of Germany, and are still being made worldwide even today. Other clocks with different themes take their inspiration from the standard bird-based clocks from history, and thanks to modern 3D printing and other technologies we can make clocks with almost any type of hour indicator we’d like with relative ease like [Jason]’s golf clock.

While the timekeeping mechanism is a fairly standard analog clock, the hour indicator mechanism in this build is a small figure which putts a golf ball into a hole once every hour. It uses an ESP32-C3 at its core, which controls a pair of servos. One controls the miniature golfer, and the other lifts the ball up into position on the green at the appointed time. Once the ball is in place, the figure rotates, striking the ball towards the hole. Although it looks almost like the ball is guided by a magnet of some sort at first glance, the ball naturally finds its way into the hole by the topography of the green alone.

Almost all of the parts in this build are 3D printed, including the green, the golfer, the frame, and a number of the servo components. There’s also a small sensor that detects if the ball has actually made it into the hole and back to the lifting mechanism, and to that end there’s also a number of configurations that can be made in the software to ensure that the servos controlling everything all work together to putt the ball properly.

While not a cuckoo clock in the strict sense, we always appreciate a unique clock around here, but if you demand your clocks have ideological purity we’ll point you to this cuckoo clock built into a wristwatch.

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Every Ham Shack Needs A Ham Clock

March 16, 2026 by 11 Comments

Every ham radio shack needs a clock; ideally one with operator-friendly features like multiple time zones and more. [cburns42] found that most solutions relied too much on an internet connection for his liking, so in true hacker fashion he decided to make his own: the operator-oriented Ham Clock CYD.

A tabbed interface goes well with the touchscreen LCD.

The Ham Clock CYD is so named for being based on the Cheap Yellow Display (CYD), an economical ESP32-based color touchscreen LCD which provides most of the core functionality. The only extra hardware is a BME280 temperature and humidity sensor, and a battery-backed DS3231 RTC module, ensuring that accurate time is kept even when the device is otherwise powered off.

It displays a load of useful operator-oriented data on the touchscreen LCD, and even has a web-based configuration page for ease of use. While the Ham Clock is a standalone device that does not depend on internet access in order to function, it does have the ability to make the most of it if available. When it has internet access over the built-in WiFi, the display incorporates specialized amateur radio data including N0NBH solar forecasts and calculated VHF/HF band conditions alongside standard meteorological data.

The CYD, sensor, and RTC are very affordable pieces of hardware which makes this clock an extremely economical build. Check out the GitHub repository for everything you’ll need to make your own, and maybe even put your own spin on it with a custom enclosure. On the other hand, if you prefer your radio-themed clocks more on the minimalist side, this Morse code clock might be right up your alley.

Building A Neatly Framed Word Clock

March 14, 2026 by 3 Comments

Reading analog clocks is a pretty straightforward skill to learn. However, if you’ve already learned to read and don’t want to pick up the extra skill, a word clock is a perfect solution for telling time. [povey_tech] found some nice examples in the wild but didn’t appreciate the price, so he set about building his own.

The build is based around an ESP32 microcontroller. While many projects in this vein would use the onboard wireless connectivity to query network time servers, in this case, the board relies on the user manually setting the time and a DS1307 real-time-clock module to keep a steady tick. Also onboard is a VEML7700 ambient light sensor, which the microcontroller uses to control the brightness of the WS2812 LEDs inside the board.

The words themselves are laser cut out of acrylic panels, with everything set inside a tidy oak picture frame. A layer of anti-reflective glass in front helps cut down on glare, while [povey_tech] was so kind as to implement two LEDs per letter to allow for lovely color gradients to be displayed. Configuring the clock is easy thanks to a webpage hosted on the ESP32 that allows for control of dimming modes, colors, and setting the time. Home Assistant integration is something planned for the future.

We’ve seen many great word clocks over the years. Perhaps the biggest leap forward in this world was the development of the addressable LED strip which made constructing these clocks much easier.

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There Are No LEDs Around The Face Of This Clock

March 10, 2026 by 8 Comments

This unusual clock by [Moritz v. Sivers] looks like a holographic dial surrounded by an LED ring, but that turns out to not be the case. What appears to be a ring of LEDs is in fact a second hologram. There are LEDs but they are tucked out of the way, and not directly visible. The result is a very unusual clock that really isn’t what it appears to be.

The face of the clock is a reflection hologram of a numbered spiral that serves as a dial. A single LED – the only one visibly mounted – illuminates this hologram from the front in order to produce the sort of holographic image most of us are familiar with, creating a sense of depth.

The lights around the circumference are another matter. What looks like a ring of LEDs serving as clock hands is actually a transmission hologram made of sixty separate exposures. By illuminating this hologram at just the right angle with LEDs (which are mounted behind the visible area), it is possible to selectively address each of those sixty exposures. The result is something that really looks like there are lit LEDs where there are in fact none.

[Moritz] actually made two clocks in this fashion. The larger green one shown here, and a smaller red version which makes some of the operating principles a bit more obvious on account of its simpler construction.

If it all sounds a bit wild or you would like to see it in action, check out the video (embedded below) which not only showcases the entire operation and assembly but also demonstrates the depth of planning and careful execution that goes into multi-exposure of a holographic plate.

[Moritz v. Sivers] is no stranger to making unusual clocks. In fact, this analog holographic clock is a direct successor to his holographic 7-segment display clock. And don’t miss the caustic clock, nor his lenticular clock.

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Building A Super-Compact Cistercian Numerals Clock

March 8, 2026 by 12 Comments

Around the thirteenth century CE, European society was in the midst between transitioning from Roman numerals to the Arabic numerals that we use today. Less remembered are the Cistercian numerals, which [BigCrimping] used for their most recent project in the form of a rather unique clock.

The Cistercian numeral system was developed by the Cistercian monastic order in the 13th century, forming a rather unique counterpoint to the Arabic numeral system. Although Arabic numerals are already significantly more compact than Roman numerals, Cistercian numerals up the ante by being capable of displaying any number between 1 and 9,999 with a single glyph.

Although for a simple 24-hour clock you don’t need to use more than a fraction of the possible glyphs, there is the complication of the Cistercian numerals not having a zero glyph, but that invites an even better take. For the version that [BigCrimping] made there are namely two glyphs that encode date and time, with the left glyph a counter for blocks of two hours and the right for seconds from 1 through 7200.

The clock is based around MAX6969 LED drivers and an ESP32 MCU on a custom PCB, with the design files including the 3D-printed enclosure available in the repository.

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The World’s Smallest Marble Clock With Pick And Place Arm

March 6, 2026 by 12 Comments

Clocks come in many styles and sizes, with perhaps the most visually pleasing ones involving marbles. Watching these little spheres obey gravity and form clearly readable numbers on a clock has strong mesmerizing qualities. If you’re not into really big marble clocks, or cannot quite find the space for a desk-sized clock, then the tiny marble clock by [Jens] may be an option.

While he totally loved the massive marble clock that [Ivan Miranda] built, it is a massive contraption that’s hard to justify as a permanent installation. His take on the concept thus makes it as small as possible, by using a pick-and-place style arm to place the marbles instead. Although the marbles don’t do a lot of rolling this way, it’s decidedly more quiet, and replace the rumbling and click-clacking of marbles with the smooth motion of a robotic arm.

Another benefit of this clock is that it’s cheap to make, with a price tag of less than $23. A big part of this is the use of cheap SG90 micro servos, and a permanent magnet along with a mechanism that pushes the marble off said magnet. Perhaps the biggest issue with this clock is that the arm somewhat obscures the time while it’s moving around, but it’s definitely another interesting addition to the gallery of marble clocks.

We have previously seen such clocks built out of wood and brass as well as 3D-printed using pendulum mechanisms, which can be made pretty compact as well, albeit with a more analog vibe.

Thanks to [Hari] for the tip.

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