Guided Filament Winder

This is a filament winder to go with a home extruder like the Filastruder. The filament drops into a loop and comes back up to the winder. At the bottom are a pair of photo resistors and a laser which monitor the position of the loop and speed up or slow down the winder so it stays in sync with the extruder. The filament is pulled up with a pinch roller based on the Minimalistic Extruder, then runs over a spring loaded arm.

The arm is mounted on a potentiometer, and its position depends on how tight the spool is pulling the filament. Using the reading of the potentiometer, the spool speeds up or slows down as needed to maintain the arm's position, and therefore tension.

On the way to the spool, the filament passes through a guide arm which is attached to a servo. Hall effect sensors detect the rotation of the spool and move the guide over the space of 1 filament diameter so the filament gets coiled evenly across the spool.

The spool mount is a PVC pipe with bearings insid