Planning the LED Christmas Lights
At first glance, slapping on strips of LED lights seems like a simple task. My biggest challenge though will be concealing as much of the wiring as possible. Since I want to leave the lights up all year long, I want the LEDs to be as inconspicuous as possible when they're not lit.
Just to recap, I'm using LED strips made up of the WS2812B programmable RGBs. Using the FastLED software, I will be able to control each LED individually, allowing for Christmas light animations and custom colors.
I also want the LED light strips to be modular, so I can install them in sections and, if need be, remove single sections if something needs to be prepared.
The best (and most inexpensive) way I can come up with to mount the LED strips is to fasten them to aluminum J-mold -- or J-trim -- which is used when putting up aluminum soffit. After some testing on a short piece, i feel the J-mold keeps the programmable LEDs a short distance from the wall, which will help 'wash' the wall in more color. The J-trim also provides a hidden channel for wires if need be. The J-mold will hold the LED strip in a nice straight and horizontal like and can be easily mounted with screws.
A sketch of the J-channel and LED strip is below.
To run the actual color changes and animations on the LED Christmas lights, I will experiment with an Arduino Mega 2560. However, after some research on the FastLED Google group, it seems that the Teensy 3.2, together with an OctoWS2811, may be required or preferred. I've already ordered the Teensy and Octo since -- even if they're not needed for this -- they'll come in handy for some future programmable LED project.
At this point I've also estimated the number of LEDs I'll need for the exterior Christmas lights. I had a one-meter strip of WS2812B LEDs that were 60 LEDs per meter. The density of LEDs seemed like overkill, so I adapted a sketch so that patterns would run on only every second LED to mimic 30 LEDs per meter. It still provided plenty of light.
I took some semi-accurate measurements of where the LED strips would be mounted on the house and the total came to 45 meters. Even though I'm still not 100% sure I'll be able to run wires where and how I want, I went ahead and ordered 50 meters off of eBay (an extra 5 meters to account for measurement mistakes and potential faults in the strips). Worst case scenario? I'll have 50 meters, or 1500 LEDs to play with if the Christmas light project falls through.