Embedded LED 3D Printed Christmas Tree

In every stage, LEDs are simply wired as a chain and first DIN and last DOU are wired to the inner regiontogether with V+ and GND for later contacting.

The stages are then connected to a 25 LED LED stripe by connection DOUT of the first stage to DIN of the next stage and so on. The tree topper LED is the last one in this chain. V+ and GND connected to every stage. The LEDs are now connected to only one pin of the microcontroller.

WS2812 LEDs are wired for every stage first. During the printing process, a color change at 5 mm halts the printer and the LEDs can be putted inside the holes of the print. also the cables were placed in the channels. 

The following picture shows the cabling from a test piece, I did during concept development:

After putting the LEDs inside and changing the filament, the LEDs are "overprinted":

This procedure is done for all four stages.