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Another take on the popular word clock. Powered by an arduino clone and WS2812B LEDs, the design was inspired first by this example, then I rewrote the firmware incorporating some ideas from this instructable using the fastled library.
My goals for this design were to have:
Largest/closest possible letters without light bleed between them Control over individual letters rather than one word at a time Suitable for hanging on a wall or sitting on a table User-friendly controls Impression of quality Laser cuttableI tried to minimize common DIY telltales like the surface finish of a 3D printed object or the burn marks/finger joints/living hinges of a laser cut project. I appreciate when someone asks me where I bought something that I designed and built myself.
I may make the laser cut parts available from time to time here on Etsy.

The main requirement for this design is access to a laser cutter that has a cutting area of 9” x 9” or greater. I am using the ubiquitous “K40” Chinese 40w CO2 laser that is available all over ebay and other overseas sites. Mine has been modified to allow it to cut a larger area (among other improvements), otherwise it wouldn’t be suitable for this project right out of the box. If you use the K40, I highly recommend using K40 whisperer instead of whatever software it came with; my SVG files are drawn with that in mind.


Laser cutter (9” x 9” area or greater, must cut wood)
Computer with Arduino IDE
Generic electronics stuff (wire cutters, strippers, etc)
Soldering iron
Hot glue gun

Wood Glue
Syringe (for applying wood glue, look for the curved plastic tip of a dental/irrigation syringe)
Hot glue
Masking tape
Paint (clock face)
Stain or paint (frame)
Disposable cups and stir stick (for epoxy face)
Wire (I used 22 gauge solid core)

1x Arduino Nano - $5 (ebay clone) to $22+ (official)
1x DS3231 RTC Module - $1 (ebay)
1x 10k Resistor - $1 for 50 (ebay)
3x Tactile switches 10mm - $1 for 20 (ebay)
1x WS2812B LED Strip 60 LED/meter - $15 to $23 (ebay)
Must be 60 LEDs per meter to have correct spacing, typically sold as 300 LED 5m rolls.
Look for the non-waterproof version
1x Micro USB breakout board (optional) - $1.25 for 5 (ebay)
1x Photoresistor 10-20k ohm range - $1 for 20 (ebay)
1x CR2032 battery - $2 for 10 (ebay)
Clear epoxy - $20 for a quart (Home Depot)
Only a few ounces are required
1x 3mm plywood - $12 for a 4’ x 8’ sheet (Home Depot)
This is usually called underlayment or Luaun
1x 1/4” x 1.5” x 48” Oak Board $5 (Home Depot)
Look for the straightest and nicest one
Paper (printer paper, or anything translucent)
That is roughly $70 dollars total, however you will end up with enough LEDs for two clocks, so it may be worth grabbing another Arduino and piece of oak and make two at the same time. Why not?”

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