This is an edited version that fixes a few things i did not like with the old version:
* Added Hold lines to have it easier to stand tall
* Added grove for star to sit in

The first version can be found here: https://www.thingiverse.com/thing:4675040.
The secound version can be found here: https://www.printables.com/model/347359-collapsible-christmas-tree-v20

There are two versions of this Christmas tree: one using the 5-point star as the base and the other using the 7-point star. The STL and STEP files for the parts of the 5-point version are designated xmasv2_5p_* and the parts of the 7-point version are designated xmasv2_7p_*.

But i have only edited the 5p version so if you want 7p you have to check V2

Easiest way to install Snowflake i have found is to push it past the holes form the back and then place it on a flatsurfice like a table and then puck each part of the tree down until they are all inline

Star and Snowflake is unchanged.

V3.1
 * Added a lip at the bottom to stop it from collapsing to far.

Printing

The segments s1 to s8 could be printed in-place together if your printer is ok with tolerances ~0.4mm. A more reliable way however, would be to print them in two batches: one for the even-numbered segments, the other for the odd-numbered. That is, print s0, s2, s4, s6, s8 first, then s1, s3, s5, s7. 

i usualy print it in 75% scale to to keep the filament usage down but still have a nice print.
using 0.6mm nozzle and 0.2mm height 

Matrerial: PLA, Silk-PLA

Settings:

Perimiteres: 3

Solid layers top/bottom:  3/3

Infill: 30%

This model was designed entirely with CadQuery - a python module for building parametric 3D CAD models.