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Since you say that the internal shafts are glued, I'd guess it's over extrusion.
There's a 0.5mm clearance between the inner shaft and the hinge.
Other option is the layer height. If you're not printing at 0.15, the support structure may fuse to the hinge.
What slicer do you use? These a setting in Cura called "Outer Before Inner Walls". Check that you're not using it (or something similar in other slicers) I think it may cause minor misalignment in a model like this.
Can you post a photo of the hinge?