Giova's Extruder

The goal of this project, started in Spring 2015, was to create a cheap and lightweight extruder, the first choose was "24BYJ48", substituted with "28BYJ-48" (Fig.1) because stronger, cheaper and easy to find.
This stepper motor is unipolar and it needs to be modified to become bipolar, there are 2 methods: the first method consists by unmounting the case (Fig.2). the second consists, in a faster and less invasive method, by cutting the plastic case and PCB, i suggest this method (Fig.3).

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