In the spring, we’re finalizing a design which has the LEDs / drive electronics safely encapsulated in an injection-molded enclosure which will look surprisingly similar to a C9 Christmas light.
However, tooling and setup fees for the machining will be very expensive. Plus, it takes a long time.
Here’s how I impatiently but quickly weatherproofed the pixels installed on the house. Click any picture to enlarge.
(Note that though this seems to work well, it took a long time and was fairly boring. Won’t be doing it again. Also, I wanted to use regular heat-shrink tubing to seal the parts. Unfortunately, the header pins and LED are so bendy that nothing sufficiently wide would make a good seal.)
To start, take an assembled, tested and programmed pixel.
Then, buy a roll of Heat Shrink Film from your local professional print shop. This is the same plastic that’s wrapped around CDs and DVDs from the store. It came in a 500 foot roll 12″ wide. If anyone needs about 485 feet of shrink film, let me know.
Buy a Foodsaver clone from Target for about $40. Useful because it has a strip of heating element which we use to make custom shapes with the shrink film.
Make a bag, sealed on three sides, out of shrink film. Mine was 12″ long by 3″ wide and open on the 3″ end.
Seal the fourth side. The plastic ‘pillow’ is now air-tight. Test the seal by mashing it with your finger. At this stage it’s important that the circuit be isolated from the rest of the world.
Ever so gently, press the 10 pins of the ribbon cable through the film. If you do it right, you’ll have 10 small punctures in the plastic. Do it wrong and the film tears and you start over.
Use a heat gun to shrink the film. It’s soft and supple when warm – almost like cellophane wrap. When it sets, it’s crinkly and stiff. Funny looking up close, totally unnoticeable from a more than a few feet away.
Attach the pixel to the ribbon cable harness previously constructed. My lights are on 8″ centers.
For even more protection, use a 1″ piece of 3/4″ diameter heatshrink tubing to lock the female and male headers together. Somewhat like a turtleneck shirt.
Et voila. I wouldn’t immerse them in water, but it works well to keep off blowing snow and rain.
