Supercharge and Convert a Unipolar Stepper to Bipolar (28BYJ-48)

this is an easy guide to convert an ultra cheap unipolar (28BYJ-48) stepper to a bipolar stepper

by converting it you will increase the torque from ~ 330 g-cm to ~800 g-cm

since the stepper is super cheap (2-3$) this is an ideal choice for low torque applications. and you will be able to use a4988 stepper drivers

Step 1: Buy Some Stuff

unipolar stepper links:

banggood

a4988 stepper drivers:

banggood

Step 2: Convert It

1- remove the blue covering over the pcb and cut trace as shown in the picture

in the process you are removing the link between the two coils .

2- de-solder the middle wire from the pcb

connect it to the a4988 like a regular bipolar stepper and enjoy;

you might need a cnc shield like this

Comments

[warhawk8080]

Just to mention it
Stock wiring in unipolar colors are Blue,Pink,Yellow,Orange,Red
With bipolar hack...coils are Blue/Yellow, Pink/Orange (red is cut off)
Otherwise the stepper on a normal bipolar driver will just jiggle and get REAL hot very fast!