This is storage for filament endings that are too long to throw out but too short to entrust to a full print.  Typically I keep them to print small portions of a print in development, to test dimensions or to see how well parts fit with each other.  So once a spool is down to just a few layers, the filament no longer justifies the huge volume occupied by a nearly empty spool.

The print comprises three parts: a section, an end, and a joint.  You can combine as many sections as you like;  for only one, print one of each part.  For more than one section, print one end and an equal number of sections and joints.  Four sections and joints will roughly match the width of a 1 kg spool.  I use CA glue to join the parts.

The .stl files were slightly improved and replaced on March 31st.  The biggest change was adding a starting hole right into the hub.  At the same time I removed the holes at the bases of the spokes.  It is possible your hub hole will need to be chased with a 5/64" or 2mm drill bit.