I have added a new Version (v2) with a narrower diameter. The diameter was reduced from 46,5 mm (v1) to 39,5 mm (v2) to fit even more brands like the Sunlu 250g spools.
This adapter allows the use of small spools (e.g. 250g, 500g, 750g) in Bambu Lab's AMS.
I have tested many AMS modifications. Some of my small spools worked very well with them, but others did not. Then I tested different adapters for small spools, but they also fit some of my spools, but not all.
So I decided to develop my own universal adapter. And here it is.
The two side parts screw into each other and can cover a flexible spool width of 35-63 mm.
This adapter can also be used to patch broken (large) spools, allowing them to continue to be used in the AMS.
The inside of the screw cap can be filled with a weight if your spool is too light.
On the outside there are grooves into which the filament end can be clamped.
I recommend using PETG or a more robust material. PLA will of course work as well if you are careful with it.
This model does not need any supports when printing.