I wanted an adjustable pill caddy for traveling. I wanted something that could adjust based on the number of days I would be traveling. 

This model has 3 parts.  Top (Lid), Middle (Mid), Bottom (Base).

The middle part is threaded on top and bottom so they can infinitely stack to the number of days desired.

I printed at .20mm Quality setting.

Update* Prusa slicer gives a warning about needed supports but I never used supports on my PLA+ prints.  Your millage may vary, would love to get any feedback.

Post Printing Note:

After printing you may need to work the threads a little to make them smooth.  I added a little petroleum jelly (Vaseline) to the threads (see picture) to help smooth them out then wiped it off with a paper towel.  Once the threads are used a little, they become very smooth. 

EDIT-UPDATE - 2024-11-10

I have added v2 of the models.  This version has slightly better thread heights to allow the section s to fight tighter together when printing with 0.15.  Also added different sizes for the middle sections:

v2-Pill-Lid

Standard Lid

v2-Mid-Taller 35

35mm Taller height

v2-Mid-Taller 30

35mm Taller height

v2-Pill-Mid-Standard (25)

25mm Original Height

v2-Mid-Short 20

20mm Shorter height

v2-Pill-Base

Standard Base

*Note: Still not sure how to force the vertical lines to align every time.  I'm playing with v3 that used knurling instead. 

EDIT-UPDATE - 2023-11-28

I have added models with250px thicker sides in the threads.  These new models (identified with “-Thicker Wall” are the same design and are compatible but with thicker walls (ie: the center diameter is slightly smaller).  This should help printers that were having a hard time with the thin wall on the original version.