I had some left-over wire taking up space on really large spools. I looked for a smaller wire spool to print, but didn't find one to my liking. I created the OpenSCAD model to be able to make any size spool you could want, within the limitations of your printer. There's even a Tie-Fighter version!

This download is the OpenSCAD only, I also have some STLs loaded. You will need a recent (after Feb 23) download of BOSL2 https://github.com/BelfrySCAD/BOSL2. Parameter names should be self-explanatory.

“spool_width” is the usable spool length, not including the spool faces. Note that “spool_outer_diam” is the diameter across the points, not the flats. My experience with PETG: “spool_cyl_thickness” can be 1 to 1.5mm. “spool_wall_thickness” can be 1.5 to 2.5 mm, on the thicker side with “honeycomb_Boolean” on.

This is a 1-piece model that requires supports. You'll want to print in the default orientation of the STL to minimize support requirements.