Swap out filament (spool) at any time

Design Rationale

Storing filament rolls with spools usually wastes a lot of space. Reusable vacuum bags are also limited (limited opening size, excessive compression can deform the spool). Various filament rolls are typically loaded onto spools. Over time, piles of empty spools become a hassle to discard or store. Although spool-less filament is commercially available, one roll usually has to be completely used before it can be removed and replaced with the next spool-less roll, which is very inconvenient. Players with various printing filaments (colors) ultimately need to prepare many empty spools, and storage will be as problematic as described above.

This empty spool completely solves the aforementioned problems. You can use a single empty spool at any time with nylon cable ties or various other straps to unload and store new or partially used filament. Then, load all spool-less filament onto the empty spool, eliminating worries about loose filament and offering greater freedom of use.