This is a track made to fit the Adafruit Neopixel LED flexible strips. I've used the 60 pixels / meter strip for the design but it should work for the other Neopixel strips as well.

This design is meant to have the pixels facing away from the viewer and placed on some sort of mounting board that will reflect the light back through the plastic providing an interesting diffuse glowing affect without the normal glare associated with these very bright LED strips. Along with the tracks, I've included end-caps that can be used to hide where the wires will connect to the Neopixel strip, a coupler to join two tracks together for longer runs, a corner joint and a three-way joint. These add some architectural interest to the tracks.

Orientation is important for the tracks which are designed to printed in halves (the same track piece printed twice). They should be printed with the outside of the track on the build plate lengthwise. The LED strip would then be inserted into the finished track piece from the top and another track piece added on top of that to sandwich the LED strip. The couplers should be printed with the top on the build plate.

These parts are design to be printed using PLA, preferrable a translucent color or natural with a 0.4mm diameter nozzel with a 0.2mm layer thickness and 1 shell. You can choose whatever infill you like. I printed them using a Marketbot Replicator 2 generation 4 using Matterhackers Natural PLA and 205 degrees C.