DIY Word Clock (part of CREST Gold)

We are surrounded by clocks these days; from our computers and phones, to our watches and walls; they are all classic analogue or digital styles. However, we can change that by making a DIY word clock that displays the time not in numbers, but in words. Buying one from the internet can be expensive, and making one yourself is far more satisfying!

This tutorial shows you my process of making a word clock where I share any advice to help you make yours faster. I constructed this as part of my CREST Gold award.

Note: You may use all these files/programs/images as you please, free of charge without crediting me. Think of it as open source!

*feel free to write a comment if you wish to ask about anything!

• Led strip (144 LEDs)
• Microcontroller (I used a Micro:bit)
• MicroUSB wire
• Multi-stranded wire
• Soldering iron
• 3mm Plywood
• 3mm clear acrylic
• 1 sheet of A4 paper
• 330 ohm resistor
• 100uf capacitor
• 4 x 40mm M4 screws (I know, that's a lot of fours!)
• 4 x M4 nuts

The word clock has 11 layers of 3mm plywood and 1 layer of clear 3mm accrylic.

The arrangement of layers is as follows, from the front to the back;

• Font panel
• Acrylic
• LED spacer - normal
• LED spacer - normal
• LED spacer - side holes
• LED spacer - side holes
• LED back plate
• Frame - LED cutout
• Frame - LED cutout & wire cutout
• Frame - wire cutout
• Frame - normal
• Back board

I designed the sketches to be laser cut in 2D Design. All the files can be found in the google drive link below:

https://drive.google.com/drive/folders/16huEPEn2lj...

Laser cutting plywood leaves some black burn marks around the cut. To get a cleaner front panel finish, flip/reflect the design horizontally so that it cuts upside down, meaning that the bottom will be cleaner. Alternatively, you can spray paint the clock black.

Great! Now that we have the layers all cut out, we can do the soldering.

The LED strip I used can be found here. Make sure to get a WS2812B strip so that you can control the LEDs individually.

The circuit diagram is shown above. The LED strip has to be cut into 12 shorter strips of 12 LEDs each, and then daisy chained together - yes, that's a lot of soldering! I just listened to my favourite podcast during these couple of hours :). We have to then connect the strip to the wire and other components in the circuit, as well as the micro-controller. If you bought a cheap micro-controller that you are willing to permanently install in the clock, it may be better to directly solder the resistor onto it.

I recommend finding a large Micro USB wire and cutting it - it should ideally be a charging cable and not a data cable. This means that it should only have two wires inside; ground and power. You should also wire strip each side to expose the metal.

My preferred method was to get a small circuit board and solder the 4 nodes to each side; the two ends of the wires, the capacitor, and the LED strip power/ground. This allows me to change the components more easily if something goes wrong, and it organises the circuitry. If doing this, I would suggest taping it down as shown in the photo as it allows you to safely solder the components.

For more information on the LED strip, I found this website to be useful.

The buffer between the size of the screws and the holes in the frames is 0mm. This means that a screwdriver and some force may be required, but it results in a more secure piece at the end.

First, the LED strip needs to be put through the small hole in the back plate so that it can rest on the back plate. Next, turn over the back plate with the LEDs under it so that the rest of the circuit is on top. Using any sort of tape, position the components against the back of the LED back board and tape them down, ensuring that none of the components are overlapping such that a short circuit can occur.

Once the back board is done, stack the rest of the back layers over the back board, ensuring that the main cable is fed through the hole. Turn over the stack again and carefully align the LED strips and put the spacers on top. If you want, you can also tape down the strips as they tend to have an adhesive back. Stack all the layers up to the acrylic, and just before putting the acrylic layer on, cut a piece of paper that fits between the last spacer and the acrylic. It should be generic white printer paper. This will help diffuse the LEDs. Once this is done, put the last two layers onto the stack and insert the screws into the corners. Make sure all the layers are aligned and you may need a screwdriver and apply some force until the screw is all the way through. Once all 4 corners are done, turn over the structure, take off the base plate and then screw on the nuts.

You should now have a structure with the base plate removed. Now for the coding!

*Regarding diffusing the LEDs, thorough testing found that the best, simplest, and cheapest way to diffuse it is just via normal white paper. I tried frosted acrylic, many fancy designs and baking sheets, but paper still remained king!

Almost there!

I had programmed the clock in the Micro:bit MakeCode editor, in JavaScript. My code is freely available here:

https://github.com/sourishs17/main-word-clock-code

https://github.com/SourishS17/word-clock-support

and the editor:

https://makecode.microbit.org/

To import and edit the code into your own environment, follow the instructions in the Github link, under the heading "Edit this project".

The code is full of comments to help you understand how it works!

Feel free to edit it as you please, redesign the entire thing, or just use it as it is :)

To download it onto the Micro:bit, connect the Micro:bit to the computer, click download in the MakeCode editor, and then drag the .hex file onto the Micro:bit. Unplug when done, and plug in the Micro USB wire from inside the clock.

Once your code is onto the Micro:bit in the clock, take off the screws from the clock and put the backplate on the clock to finish it off!

*note, the code is still being polished but is functional as it is.

Now that you've got a working clock, see what else you can do it - have fun and explore!

Here are some ideas to get your creative juices flowing:

• Try using coloured paper as the diffuser
• Mess with the code to see what other functions you can add
• Design your own birthday animation in the code
• Use a material other than wood
• Try creating a PCB for the electronics
• Perhaps use another microcontroller like the Arduino or Raspberry Pi
• The LED grid is really a screen in itself - so you can use each LED as a pixel and design some fun games?
  • EDIT: I've managed to code Snake on it!
  • video demo
  • clock code
    
  • controller code

I hope you enjoyed my project and making a word clock yourself :)

Thank you for reading until the end!