This is a LED pocket watch. It has 12 LEDs to show the hour, 60 LEDs to show the minute, and 60 LEDs to show the second. The LEDs are arranged in three rings. There is a button on the top to activate the pocket watch, and a button on the back to change modes and settings.

The battery is a rechargable lithium ion coin cell battery and it is charged from a micro USB connector. The battery life depends on how heavily the pocket watch is used, but if you leave it alone, it is estimated to last several months. There is a low battery indication feature. This pocket watch also feature a buzzer and a vibration motor, which are used for the alarm feature, and the motor causes a short "tick" as each second passes by. The pocket watch is constructed of a PCB, two pieces of laser cut clear acrylic plastic, and a 3D printed casing.

All the files are also available from my Github (there is a single ZIP download option on that page). This will include the microcontroller source code, circuit schematic, PCB layout, laser cutting vector file, and 3D models. Everything is open source, and also ready to be sent out for fabrication.

Step 1: Inspiration and Design

This isn't the first LED pocket watch to exist (I saw this one), I want one of my own, and when I want something, what I really mean is I want to build something. There are some flaws in other designs that I didn't like, so I have my chance to improve upon those flaws.

The top three goals are to look good, user friendly, long lasting.

It is very common to see LED pocket watches that do not have all 60 LEDs for the minute "hand", some have only 12. I really want a clear indication of the current minute with no guessing or estimation involved. So I decided to use 60 LEDs.

I want 60 LEDs for the second "hand", and some of the other designs do not feature a second "hand" at all. As the seconds change, it creates motion, which gives the viewer a feeling of confidence and pace. You will feel confident that the watch is working, because you can visually see each second tick away. Plus, it will look prettier.

There are 12 LEDs for the hour "hand", not 60. Although following the behaviour of an analog clock might sound good, it makes it a bit slower to visually interpolate the current hour.

I explicitly chose not to use bicolor or tricolor LEDs. I want three rings because the different radiuses helps me distinguish between the different "hands" faster.

Right now I check the time using my phone, I'm sure a lot of you do too. So I decided I wanted it to have the size that fits comfortably in my hand, just like my phone, and I wanted a single button to activate it, just like my phone.

I wanted this to be something I use daily, it must be durable. Most of the time it will be in my pocket. A casing is required to protect the circuitry from junk inside my pocket. The casing also has a hole, so I can attach it to a chain.

Nobody likes replacing batteries, especially when it is stuck inside a case. So I decided to use a rechargable battery. The easiest battery charging method today is probably by using USB, all you need is a cord and a USB port.

The buzzer and motor feature are basically just fancy additions because I can do it. I'm not limited on cost, and they will physically fit in the design, so why not?

I made one that is black and green because green is the cheapest PCB color and I have a preference for black. The purple edition is because OSH Park makes purple PCBs, I wanted a case to match the color, why not make two and see if I like it.

As I am coming up with my goals, I also have to consider the materials and equipment I have access to. PCB, laser cutting, and 3D printing services can be found online and I am already very familiar with all three of these techniques.
<p>yo frank, i looked at the gif, and i was like MAN SLOW DOWN, YOUR WAY TO GOOD FOR ME</p>
A very neat work indeed
Friends is their anyone who can help me in programming an at mega 16a microcontroller through avr studio.<br>Currently I do the programming with progisp software using usbasp programmer.<br>I don't know how to write the codes and make a hex file<br>Thanks in advance
Thats neat
Is there a reason not to make your LED matrix something like 11x12 so that you only need 23 pins (+2 for the buttons), other than the fact that you would need 11 current limiting resistors instead of 5? Seems like it would be easier to source a more common microcontroller (I'm thinking ATmega32u4). Great Instructable by the way.
Sourcing the ATmega645 wasn't hard at all <br> <br>One reason why I didn't pick 11x12 is it would've made the code and schematic slightly more complicated. I didn't manually layout the LEDs, I used EAGLE's scripting to automatically do it for me. <br> <br>There is nothing stopping you from doing the same project with a 11x12 matrix. <br> <br>Personally I think a larger chip looks better. That's a subjective advantage of the ATmega645 over the ATmega32U4. If you made the pocket watch smaller overall, you might choose a smaller chip.
very impressive frank,,, chanceless ...\\\\\\\\\\\\\\\\
This thing is amazing. If I were interested in purchasing one already completed, would that be possible, and how much would it cost me? <br>I'm a bit of a novice when it comes to soldering, and I'd love for my finished product to look as good as yours does. <br>Thank you for your time and consideration.
Congratulations on the win!
That is a beautiful PCB, and I love the animations. <br>You couldn't have done a better job with this, from design to documentation. It's incredibly inspiring to see a project that is so complete! <br> <br>Not to get overly philosophical, but I think projects like these are the future. The tools needed to design and manufacture near-consumer level products are becoming accessible to the people with the ideas to use them. It makes me feel all warm and fuzzy. Hats off Frank, Amazing work!
To tell the truth I'm a little dyslexic, so I look at pitchers more than words - I thought this was a glow in the dark Combination Lock, I must be tripping, still very cool.
this is an obscenely elegant and perfect DIY project for an LED pocket watch. not only is the design solid, it is extremely aesthetically pleasing. <br> <br>great job!
you should definitely make this into a kit <br>
You say there's plenty of room, and it could be made smaller. If so, would it be possible to add another ring of LEDs for miliseconds? And would the microcontroller be able to handle that?
I really like this design! I want to think that I've seen it somewhere else before, a few years ago, and I really wanted to make one then. Do you think that this PCB design would scale down enough to make it fit into an actual pocket watch case and still have enough room for all the components?
If you've kept an eye on HackADay, you have seen this concept before, in an actual Elgin case. The site is here: http://www.eng.yale.edu/pep5/pocket_watch.html Last I heard from the creator for that version, (a few days ago), v2 &amp; kits are still in the works.
There is plenty of room, and also the LEDs are not as tight as physically possible yet. So it is definitely possible to make it smaller.
Cool gadget man!
Truly amazing. Great work!
really epic job with in a professionaly way by the scratch a uncompetitive product. <br> <br> <br>Respect 1^3*n
Oh man; I wanna create this and put a vintage-looking face on the display.
That is P I M P. Id buy one from you, I can't concentrate on anything for 6 hours and have it look any good!
The 132 LEDs are soldered <strong>BY HAND ?!&nbsp; </strong>I mean, I admire your tenacity - just&nbsp; to solder them in place somehow would be hard enough. But they are in a nearly perfect circle - that's what blows my mind. You must have inhumanely steady hands. Great job!&nbsp;
that took 6 hours, it's actually not fun and the air quality in my room becomes a serious concern.
Very well done! Similar in concept to this: <br>http://www.solsuno.com/ <br>Would buy in kit form!
This is very nice. I think the only thing that bugs me about it is how loud it is just clicking off the seconds. I'm big on quiet. <br>We are indeed living in the days of multitasking, so it would be nice if the pocket watch also included a camera, light, etc.
Love the design. I think it would be cool if after the seconds LED moves forward, another 'pulse' races around the dial to push the seconds forwards (simulating 1/60th of a second or 16.7ms)
Nice job,a true pro.at watch making.
very nice work ////this would be great for people like me who find it hard to see Mickeys hands without glasses on and forget to wind him ......wonder if I could con uhhhh errrr talk my son into making me one
Wish I wasn't lazy, I'd make one, awesome work!
Amazing project and documentation! Thank you.
I love it!
This is awesome!
This looks very similar to another LED pocket watch I've seen on the internet: <a href="http://www.eng.yale.edu/pep5/pocket_watch.html" rel="nofollow">http://www.eng.yale.edu/pep5/pocket_watch.html</a><br> <br> Both are very cool.
Thank you so much for taking the time to document this project so well. It was fascinating to go through your thought process on the project, step by step. I learned a lot from you today!
Very professional. I'm an electrical engineer and love to do CNC work. You've taken things to the next level. Consider selling kits - I think they would be a hit. Test market on Kickstarter, if you're interested. On the other hand, life's short, just have fun with it. <br>Nice job.
CNC is a step above me, if I had a CNC machine, then I wouldn't have to order the 3D printed parts all the way from Europe. <br> <br>Maybe after I graduate, I'll think harder about selling things.
Excellent Instructable! I'm an EE too. Is this what they teach in EE now? Very well documented and executed. Keep up the great work.
Ha no, my none of my undergrad classes in EE teach anything remotely close to this. My classes almost always teach only theory. My classmates won't understand what FR4 is. I know people who have blown two BeagleBoards because they put 5V into a 3.3V pin. Nobody teaches us how to solder except for one safety video they posted online. Any project that uses more than an amp requires special permissions. <br> <br>I'm just lucky that I actually like doing this stuff in my spare time.
It is professional! <br>
I love the design... I'd love to make anr/or have a watch like that, but it's way above my skill level... I'll stick to admiring your design ;).
Wow, I am absolutely floored at the level of professionalism and work that you put into this watch and instructable. It really shows in the final product all the time and care you took to make sure that everything was perfect.

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Bio: I am an electrical engineer. I graduated from U of Waterloo. I used to work for Adafruit Industries as an EE. Now I work for ... More »
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