This spool is designed to take Ziro cardboard spools and make them work better with the AMS. In recent orders I started receiving cardboard spools instead of plastic, and I was having periodic issues with them in the AMS. The spools are narrower than many, and the core is smaller, so they did not fit any of my existing spools/adapters, so I made this. The outside dimensions of this spool (outer rim diameter and total thickness) match Bambu spools, so they fit the AMS perfectly, while the inner dimensions (hub diameter and thickness) match the Ziro spool, so the filament plus core fits perfectly.

The design and the names ended up backwards and I haven't gotten around to fixing it… the half that is called “narrow” has the narrower core, but the thicker spokes, and the half that is called “wide” has the wider core but the narrower spokes. I kept the “wide” and “narrow” names consistent with the original bambu reusable spool.

Using it is like taking any cardboard spool and putting it onto a reusable spool. It's quite easy after you do it a time or two.

1. Look inside the spool and see which side of the core has the end of the filament in it. Start with the OPPOSITE side, the side that does not have the filament end, and carefully rip off the side of the spool. Clean up any glue or cardboard that is blocking the hole in the core and the slot.
   
   
2. Place the “wide” side of the reusable spool down onto it. Make sure to line up the slot in the cardboard core with the corresponding part on the spool, so the spool sits down flush onto the cardboard core.
   
   
3. Carefully flip it all over and then rip off the other side and clean up the core.
   
   
4. Place the "narrow" side of the spool down into it. The locking tabs have a large and small so make sure they are lined up correctly and the two halves of the spool are fully seated and flush with the cardboard core.
   
   
5. Rotate the “narrow” side clockwise to lock the sides together.
6. Flip the complete spool back over and insert the two locks into the slots in the core.