I needed a sewing spool with an extended thread capacity for a Singer sewing machine.
This is a two pieces model. A main body and a cap which are join with their sidewalls only. This way it can be printed without support. The spool fits to the spindle on the top of the sewing machine.

Parameters:
- Outer diameter: 20mm
- Inner diameter: 9mm
- Hole diameter (fits to the spindle): 6.2mm
- Internal (usable) length: 48mm

Print instructions for 0.4mm nozzle:
Default settings in prusaslicer. I used layer height 0.20mm Structural.

Assembly instructions:
Just squeeze the pieces together.

Hint:
When you fill the spool it might be necessary to help to the machine with your hand to make the thread even on the spindle otherwise most of the thread go to the bottom.

Material: PETG suggested.

Printing time: 28m
Filament: ~3g