Install a Low-Friction Filament Delivery System

To prevent buckling caused by external drag, modify the filament delivery path:

1. Replace the standard spool holder with a high-quality, bearing-based spool holder to ensure the filament unspools with near-zero resistance.
2. Minimize the distance between the spool and the extruder inlet; if possible, mount the spool directly above the extruder to create a vertical, gravity-assisted feed.
3. Remove any unnecessary Bowden tubing or restrictive filament guides between the spool and the extruder, as any drag at this stage forces the soft 70A TPU to compress and buckle before it even reaches the drive gears.

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