NeoPixel strips are great when all you want to do is go in a straight line, but what about when you want to make a turn?
Here is a simple little board that makes it easy and keeps perfect spacing on both axes.
This one is laid out for 60 pixel/meter strips, but could be adjusted for other pitches.
All of the traces have 1/32″ clearance, so you can cut a bunch of them on a CNC milling machine in one pass.
OtherMill Porn
By luck, one-sided FR1 board happens to be about the same thickness as 3M 1/2″ foam tape, so you can run the tape up to the board and everything comes out flat.
Full gerbers and diptrace files here…
https://github.com/bigjosh/NeoPixel-Corner-Board
The diptrace files include footprints and components for the chip and a footprint for the edge connections.
Strips to Chips
If you have a hot air station you can easily pop a chip off a strip by holding it over ~320C air for about 3 seconds and then grabbing it with a tweezers.
Power and Data
If you are making a full rectangle, you can neatly inject power and data by soldering a connector to the back of the strip and then punching a hole though the Data Out line after the last chip in the loop. I used a leather punch. 
This works especially well because the power now flows down both sides of the rectangle at the same time. Because there are now two paths for the power to get to the farthest point, you can make things twice as large compared to a rectangle where the current flows linearly around the loop.
Note that the wires I used were a little thicker than the foam tape so I had to drill a hole behind them to keep everything flat.
Why DipTrace?
Listen, I know everyone loves Eagle, but I find it physically painful to use.
KiCad has some very nice features (especially interactive routing… but only if you know to switch graphics modes! WTF?) , but after wasting an hour trying to do this stupid little board I gave up and switched to DipTrace and got it done in 10 minutes.
Sadly, they don’t seem to be updating it much anymore. I don’t blame them – it is hard to compete on the low end with all the crappy-but-free PCB software out there. Still, if you are…
- on Windows
- hate Eagle
- just want to get your board done
- don’t care about people heckling you
…then give Diptrace a try. It is not perfect, but it is a pleasure to use and you can be productive and get real work done less than an hour after installing it.