I think the addition of 2D support in WLED 0.14 will spark a lot of interest in making LED curtains and DIY 2D matrices. And the new PVC coated addressable fairy lights are perfect for making a large serpentine matrix. They have a much thinner profile than WS2811 pixel/bullet strings and the LEDs stay in line and in position. With the WS2811 pixels, you need extra hardware to keep the pixels properly positioned. If you are building your matrix on a wall, LED strips are a good option. However, that involves A LOT of soldering, they draw a lot of power, they need waterproofing if deployed outdoors, and they need a separate form of diffusion.
In contrast, fairly lights draw much less power, have built-in diffusers, are waterproof, have a very slender profile, and require very little soldering to build a serpentine matrix. And unlike older fairy lights, most of the new PVC coated fairy lights are not fixed addressed and work just like normal WS281x lights. I have been building matrices in large windows and the fairly lights are innocuous during the day and display beautifully at night. The biggest drawback of fairy lights is the 10cm / 4in spacing. To build a 32x32 matrix at that spacing, you would need a 3.2m / 10.5ft space. Probably not practical for most users. However, if we could shrink the spacing to 5cm / 2in, a 32 x 32 matrix would fit quite nicely in most picture windows. The problem is, only one manufacturer (Ray Wu) was making 5cm pitch fairy lights, and the cost + shipping is about $15 per 100 lights.
But being the cheapskate that I am, I set out to convince some other manufacturers to make 5cm pitch (20 LED / meter) fairy lights. I’m happy to report that I got some great deals for our community. One is available right now, the other is being manufactured and will be available in about 2 weeks. The supplier is currently only selling these to us (for reasons I will get to in my review below), so you will have to use the link to find it. The cost is $16.99 for 400 LED / 20m with free shipping. Meaning you will be able to build a 32x32 matrix for under $50!
Know Shine Review:
My biggest gripe on these lights is that the wire is very thin, 26AWG. Whereas most other fairy lights are using 24AWG wire. On a per pixel basis, they did not seem as bright as the copper epoxy coated fairy lights. However, given that there will be 4 times as many lights (compared to 10cm string), they are bright enough. You can get full brightness for 100 pixels on either side of a power injection (inject at 0, 200, 400, 600 etc). I measured 100 lights at full bright white and they drew 0.98A. I’m powering my 28x36 matrix with a 12A supply. The outside wire with gold stripes is 5V, the outside silver wire is ground. The manufacturer says to connect both center wires to data, but if you are splicing two strings together, be sure to attach the interior wires separate, gold to gold and silver to silver.
GFLAI
I was not as happy with the build quality from GFLAI. I had several sections that I had to cut out because the spacing was off by 1cm or more, and some of the epoxy beads were much larger or much thinner than the others. They currently have 10cm lights for $2.80 per 100. If their site still says free shipping on orders over $80, please note this does not apply to the fairy lights. They ship using DHL so plan on spending $40 - $100 on shipping. But if you are buying in bulk, this is the way to go. And if you were installing on a roof line instead of building a matrix, the occasional variation in spacing or bead size would not be an issue.
One other note as you are calculating how many lights you’ll need for your project. The spacing between pixels is 5cm / 2in. But due to the length of the epoxy bead, there is only 3.8cm / 1.5in of wire between beads. So either plan on 1.5in spacing in one direction or devise something to offset your strings after the first and last bead in each row.
