About the Cardboard Spool Arbor Rings
Fits Overture Cardboard spools (and others?) with ~2.165 inch (55mm) ID. Should be a pretty snug press-fit. Remove them and re-use them.
Likely can be scaled up or down in XY to fit other size spools. These have tapered ribs on them meant to dig into the cardboard.
We use them with our spool holder clip when printing TPU and other filaments that don't sit in the AMS unit of the Bambu X1C (or P1P).
We had printed these with a 0.6 nozzle, solid, at 0.3mm layer height. But pretty much any settings solid should work well.
This is originally a remix of this spool arbor from Filaments.ca