I have been using stepper motors for a while now, and they are fantastic for all sorts of robotic projects.
Today I will share the things I have learnt so far about reusing old stepper motors salvaged from printers. Identifying Stepper Motors
Stepper motors are easily identified by their shape, the number of connecting wires and the vibration you feel when you turn the shaft. I have been using old stepper motors take from old photocopy machine, print or scan and test with Arduino and A4988 Driver