Turn your empty Bambu cores into a handy storage container! This design is specifically for Bambu cardboard cores and won’t work with other brands as far as I know.
 

I noticed a few cores weren’t fitting initially; it’s just the outer edge that’s flared out. Simply roll the outer edge of the spool on your desk to compress it, and problem solved!
 

The Center adapter is tight fit, you don't want that coming apart. I feed one side in and press it in around the core until seated.  

NO SUPPORTS NEEDED

As I print more of these, the cardboard core is quite inconsistent on the outside dimension, Some being extremely loose some being tight. As I get feedback we will make adjustments as needed to work for the Majority.