Sundials, one of humanity’s oldest ways of telling time, are typically permanent installations. The very good reason for this is that telling time by the sun with any degree of accuracy requires two-dimensional calibration — once for cardinal direction, and the other for local latitude.

[poblocki1982] is an amateur astronomer and semi-professional sundial enthusiast who took the time to make a self-calibrating equatorial ‘dial that can be used anywhere the sun shines. All this solar beauty needs is a level surface and a few seconds to find its bearings.

Switch it on, set it down, and the sundial spins around on a continuous-rotation servo until the HMC5883L compass module finds the north-south orientation. Then the GPS module determines the latitude, and a 180° servo pans the plate until it finds the ideal position. Everything is controlled with an Arduino Nano and runs on a 9V battery, although we’d love to see it run on solar power someday. Or would that be flying too close to the sun? Check out how fast this thing calibrates itself in the short demo after the break.

Not quite portable enough for you? Here’s a reverse sundial you wear on your wrist.

If we asked you to rattle off all the tools at your own personal disposal, you’d probably leave your timepieces off the list. But we say clocks are definitely tools — cool tools that come in countless forms and give meaning to endless days.

A clock form we hadn’t considered was that of an actual tool. So we were immeasurably delighted to see [scealux]’s clock made from a measuring tape. At least, the time-telling part of the clock is made from a measuring tape. The case isn’t really from a tape measure — it’s entirely printed, Bondo’d, sanded, and painted so well that it’s quite easy to mistake it for the real thing.

Tightly packed inside this piece of functional art is an Arduino Nano and a DS3231 precision RTC module, which we think is fitting for a tool-based clock. The Nano fetches the time and drives a stepper motor that just barely fits inside. There’s just enough tape wound around the printed hub to measure out the time in increments of one hour per inch. Take 1/16″ or so and watch the demo and brief walk-through video after the break.

Not all tools are sharp, and not all clocks are meant to be precise. Here’s a clock for the times that gives you the gist.

Good clocks are generally those that keep time well. But we think the mark of a great clock is one that can lure the observer into watching time pass. It doesn’t really matter how technical a timepiece is — watching sand shimmy through an hourglass has its merits, too. But just when we were sure that there was nothing new to be done in the realm of 7-segment clocks, [thediylife] said ‘hold my beer’ and produced this beauty.

A total of 28 servos are used to independently control four displays’ worth of 3D-printed segments. The servos pivot each segment back and forth 90° between two points: upward and flat-faced to display the time when called upon, and then down on its side to rest while its not needed.

Circuit-wise, the clock’s not all that complicated, though it certainly looks like a time-consuming build. The servos are controlled by an Arduino through a pair of 16-channel servo drivers, divided up by HH and MM segments. The Arduino fetches the time from a DS1302 RTC module and splits the result up into four-digit time. Code-wise, each digit gets its own array, which stores the active and inactive positions for each servo. Demo and full explanation of the build and code are waiting after the break.

When it comes to 7-segment displays, we say the more the merrier. Here’s a clock that uses pretty much all of them.

Have you ever looked at the time, and then had to look again because it just didn’t register? This phenomenon seems more prevalent with phone timepieces, but it’s been known to happen with standard wall clocks, too. This latest offering in a stream of unusual clocks fashioned by [mircemk] solves that problem by forcing the viewer to pay attention as the time flashes by in a series of single digits, separated by a hyphen.

Inside the boxy blue base is an Arduino Nano, a DS3231 real-time clock module, and a perfboard full of transistors for switching the LED strips inside the segments. There’s an LED on the front that blinks the seconds, and honestly, we’re kind of on the fence about this part. It would be nice if it faded in and out, or was otherwise a little less distracting, but it did grow on us as we watched the demo.

We love the way this clock celebrates the seven-segment display, and only wish it were much bigger. The STLs and code are available if you want to make one, though they only cover the 7-segment part — the base is made of foam board. Check out the demo and build video after the break.

Would you rather hear the time go by in gentle chimes? Here’s chime clock that uses old hard drive actuators.

Timepieces are cool no matter how simplistic or granular they are. Sometimes its nice not to know exactly what time it is down to the second, and most of the really beautiful clocks are simple as can be. If you didn’t know this was a clock, it would still be fascinating to watch the bearings race around the face.

This clock takes design cues from the Story clock, a visual revolution in counting down time which uses magnetic levitation to move a single bearing around the face exactly once over a duration of any length as set by the user. As a clock, it’s not very useful, so there’s a digital readout that still doesn’t justify the $800 price tag.

[tomatoskins] designed a DIY version that’s far more elegant. It has two ball bearings that move around the surface against hidden magnets — an hour ball and a minute ball. Inside there’s a pair of 3D-printed ring gears that are each driven by a stepper motor and controlled with an Arduino Nano and a real-time clock module. The body is made of plywood reclaimed from a bed frame, and [tomatoskins] added a walnut veneer for timeless class.

In addition to the code, STLs, and CAD files that birthed the STLs, [tomatoskins] has a juicy 3D-printing tip to offer. The gears had to be printed in interlocked pieces, but these seams can be sealed with a solution of acetone and plastic from supports and failed prints.

If you dig minimalism but think this clock is a bit too vague to read, here’s a huge digital clock made from small analog clocks.

[Lewis] of [DIY Machines] was always on the lookout for that perfect something to hang above the couch. After spending a lot of time fruitlessly searching, he designed and built this awesome shelving unit with recessed lighting that doubles as a huge 7-segment clock.

The clock part works as you probably expect — an Elegoo Nano fetches the time from a real-time clock module and displays it on the WS2812B LED strips arranged in 7-segment formations. There’s a photocell module to detect the ambient light level in the room, so the display is never brighter than it needs to be.

Don’t have a 3D printer yet? Then you may need to pass on this one. Aside from the wood back plane and the electronics, the rest of this build is done with printed plastic, starting with 31 carefully-designed supports for the shelves. There are also the LED strip holders, and the sleeve pieces that hide all the wires and give this project its beautifully finished look.

You may have noticed that the far left digit isn’t a full seven segments. If you’re committed to 24-hour time, you’d have to adjust everything to allow for that, but you’d end up with two more shelves. Given the fantastic build video after the break, it probably wouldn’t take too long to figure all that out.

We like big clocks and we cannot lie. If you have room for it, build something like this blinkenlit beauty.

When [tnjyoung] was asked to build a huge lighted clock for a high school theater’s production of Cinderella with only two weeks before opening night, he probably wished for a fairy godmother of his own to show up and do it for him. But he and his team pulled it off, and it looks amazing. That medallion in the middle? It was laid out painstakingly by hand, using electrical tape.

This thing is 12 feet wide and weighs more than 500 pounds. Even so, it isn’t a permanent set piece, so it has to move up and down throughout the show on airplane cables. Now for the minutiae: there’s an Arduino Uno with built-in Wi-Fi that receives UDP commands from a phone to raise and lower the clock at the appropriate times. The ‘duino is also controlling two stepper motors, one for the hour hand and one for the minute hand.

Time is almost a minor character in the story of Cinderella, since she has to get back by midnight. Because of this, [tnjyoung] programmed a dozen or so time cues that move the steppers at various speeds to achieve different effects, like time flying by as she dances the night away with the Prince. Hour you still just sitting there? Sweep past the break to watch the build process fly by in a matter of minutes.

Got all the time in the world? Make a clock out of clocks. Clocks all the way down.

When you read “Arduino wristwatch”, you fall into the trap of envisioning an Arduino UNO clumsily strapped to someone’s wrist. [Marijo Blažević’s] creation is much more polished than that. A round circuit board holds two surface mount ICs and 12 LEDs. The whole thing looks nice fit snugly inside of a watch body. It isn’t a Rolex, but it does have considerable geek cred without being unwearable in polite company.

Once IC is an AVR micro, of course. The other is a DS3231 real time clock with built-in crystal. A CR2032 keeps it all running. The main body, the outer ring, the bottom, and the buttons are 3D printed in PLA. The crystal and the band are the only mechanical parts not printed. The bill of materials shows a 36mm crystal and even provides links for all the parts.

You don’t want to run LEDs all the time because it is bad on the battery. When you press the button once, you get one of the LEDs to light to show the hours. Another press reads the minutes in units of 5 minutes. A third press shows you one of five LEDs to show how many minutes to add. For example, if the time is 9:26 you’d get LED 9 (hours), LED 5 for 25 minutes, and the third press would show LED 1 for 1 extra minute. If either of the minute indicators show 12 o’clock, that indicates zero minutes.

The exciting thing, of course, is that you can program it beyond the code on GitHub. Already it can tell time and display the temperature. You don’t have a lot of I/O, but you ought to be able to get some more options and maybe some flashy LED blinking patterns in if you try.

You say your binary clock no longer has the obfuscation level needed to earn the proper nerd street cred? Feel like you need something a little more mathematically challenging to make sure only the cool kids can tell the time? Then this Fibonacci clock might be just the thing to build.

Granted, [TecnoProfesor]’s clock is a somewhat simplified version of an earlier version that was nigh impossible to decode. But with its color coding and [Piet Mondrian]-esque grids, it’s still satisfyingly difficult to get the time from a quick glance. The area of the blocks represents the Fibonacci sequence 1, 1, 2, 3, 5, and adding up which blocks are illuminated by the RGB LEDs behind the frosted front panel. That lets you tally up to 12 intervals; for the minutes and seconds, there are indicators for the powers of 12 up to 48. Put it all together and you’ve got a unique and attractive graphical time display that’s sure to start interesting conversations when the mathematically disinclined try to use it. Check out the video below as the clock goes from 12:28:01 to 12:28:46. We think.

If this doesn’t scratch your itch for obfuscated clocks, we’ve got plenty of them. From random four-letter words to an analog digital clock to an epic epoch clock, we’ve got them all.

There are a great many display technologies available if you wish to make a digital clock. Many hackers seem to have a penchant for the glowier fare from the Eastern side of the Berlin Wall. [ChristineNZ] is one such hacker, and managed to secure some proper Soviet kit for an alarm clock build.

The clock employs an IV-27M vacuum fluorescent display, manufactured in the now-defunct USSR. Featuring 13 seven-segment digits, it’s got that charming blue glow that you just don’t get with other technologies. A MAX6921AWI chip is used to drive the VFD, and an Arduino Mega is the brains of the operation. There’s also an HD44780-compliant LCD that can display further alphanumeric information, and a 4×4 keypad for controlling the device.

The best part of the build though is the enclosure. The VFD is encased in a glass tube, and supported at either end by 90-degree copper pipe couplers. These hold the VFD aloft, and also act as a conduit for the wires coming off each end of the tube. It’s all built on top of a wooden base that holds the rest of the electronics.

It’s an attractive build, and we love the floating look created by the glass tube construction. It’s not the first time we’ve seen old Russian VFDs, and we doubt it will be the last. Video after the break.

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