When you are using the original spoolholder of the BambuLab X1 and you have also the AMS installed, you are still not able to use wider spools. The SpringBuffer is in the way. With this simple 20mm spacer a wider spool is usable. It is strong enough for 1 kg-rolls. The M3 screws/bolts must be 27-28 mm (length original screws + 20 mm).

Update: on request there is a new version added for M3x30, it is 3mm longer.

There is a dent on one of the sides, that is supposed to be at the right bottom. It is there to give the tube from the springbuffer a straight as possible path outside the buffer (it is important that it can move as freely as possible).

Happy spooling :)

Notes:

4 walls and 4 for bottom and top, 30% infill

I fix the hols for perfect fit