Intro: Programmable Led Bar
What I've done is practically only holder for WS2812b leds. But it's more, it's stylish. You can mount it wherever you want and it's fully 3d printable. I've mounted it on my R/C car, but you can program it to be a weather station or it can be an extraordinary headlight.
Step 1: Parts Needed
Firstly you will need at least 33 of WS2812b leds, but I suggest buying more, because you may damage some during soldering.
Then you have to 3d print the main part. Also you should gather wires and some conductive material too.
As conductive material I'm using legs of resistors or leds- basically a scrap from soldering circuit boards.
Soldering iron and soldering skills are necessary
Step 2: Printing the Main Part
Leds must fit in the main part with a little force, so you wouldn't have to glue them and they won't fall off. To ensure that holes will be perfectly sized, I've made small calibration part. At first print calibration part and test whether the holes are enough tight. If not, change scaling in your slicer.
Step 3: Soldering
I was soldering it by segments. During soldering gripper was very useful. Soldering temperature shouldn't exceed 300°C.
At first I put leds in the right place. Note the direction of arrow. Then I soldered them together in lines and then soldered lines together with wires.
Step 4: Finish
Now you should have built original led bar which can be used in many ways. It depends on you. For programming I'm using FastLED library which I think is the best.