This straight spool holder is proper solution for anyone who has a good 5-10cm space on their side and want to keep the spool there. I've got a HiFi container and it was my chance to shine and design this solution.  It has the original Bambu pattern with extra features for later implementations. 

Notes

• There are 3 pieces. 
  • The base, which slides onto the original small spool arm slot.
  • The adapter, which is inserted into the base.
  • The screw, which locks the adapter and prevents the spool from falling. 
• The straight spool holder is “angled”, which means that it has a proper space/tolerance that allows the arm to go back and forth slightly to avoid snapping it when the filament is stuck. This is by choice. If you wish to have a straight - straight version without any visual enhancements, please let me know in the comments.
• Additional slots:

  • Screws are M5 with 12mm depth. These four screwing holes are the middle points of a rect (width 27.95 mm length 30mm) 

    

  • The second slot is a rect 13x13mm with fillet of 4mm

    

This needs my solution “Extended Filament Guide holder” in order for it to work well. You can find it here:  https://makerworld.com/en/models/972656

How-To:

Step	Description	Image
1	Print the utilities
2	Print the base you want (currently, angled base is available)
3	Insert the adapter into the slot. Screw the spool lock named “Screw”
4	Slide the whole solution into the original piece

Current A1 Mini solutions

Feel free to check the current list of A1 mini solutions. They will be updated very soon! 

Title	Link	Image
Straight Spool holder	https://makerworld.com/en/models/972659
Filament Guide Long extension	https://makerworld.com/en/models/972656