How to replace the Y motor (BCN3D Sigma)

In this article you will learn the procedure to change the Y motor


Allen 2mm


Allen 1.5mm
Socket wrench 5.5mm 

To replace the Y motor, first, turn off the printer and unplug it from the power outlet.




2. Unplug the motor cable from the Y driver.



3. Remove the Bowden tube to have access to the motor screws.

_MG_2340 _MG_2342


4. Partially loosen the nuts that hold the motor in place with a 5.5mm socket driver. nut-iconx2 M3



Tip: You may have to reduce the belt tension by loosening the two screws placed under the belt tensioner with a 1.5mm Allen key.


5. Take out the Y motor from the stepper holder by loosening the screws that hold the motor in place. screw-iconx3 M3x6mm


6. Install the new pulley on the motor.


Tip: Make sure to tighten the set screw on the flat face of the motor's shaft. 


7. Attach the motor to the stepper holder and install it back on the printer’s structure, making sure that you adjust the tension screws again.



To finish the assembly process, follow the process from Step 3 to Step 2 in inverse order. 


It's important to keep your printer in good shape to make the most out of it. In this chart, you can find a list of the extruder maintenance procedures and how frequently these should be done. Maintenance Plan


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Repair didn’t go as planned? Check out our forum community for troubleshooting help.


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Parts   Buy these parts
motor y assembly BCN3D Sigma/Sigmax Y motor + Heatsink SKU 16015


adjust belt tension eng pulley noise eng


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