How to replace the X motor (BCN3D Sigmax)

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



2.5mm Allen wrench


1. To replace the X motors, first, turn off the printer and unplug it from the power outlet.



2. Loosen the two endstop screws to have access to the X motor screw. Once the endstop has been removed, loosen the X motor screw.  screw-icon 2x M3x10mm 

screw-icon 1x M3x6mm



3. Cut the two zip-ties that hold the motor cable and then lose the other three X motor screws.

 screw-icon 3x M3x6mm


Tip: Be careful! Make sure not to cut the cables along with the zip ties. 


4. Once the original motor is removed, Install the pulley on the new motor at the same height as it was on the original with the help of a caliper.

Make sure to align the pulley screw with the flat shaft face.


The left motor pulley should be mounted with the geared shaft on top and should be 4mm apart from the motor itself

The right motor pulley should be mounted with the geared shaft at the bottom and should be 2mm apart from the motor itself.

x-motor-L x-motor-R

Tip: Make sure to tighten the shrub screw on the square face of the motor's axle. 


5. Place the motor in the stepper holder, making sure that the belt is properly installed in the pulley.


6. Once the motor is in place, connect the motor cable to the driver board and wrap the zip-ties around the cables to secure them.


Tip: Notice the slots in the sides of the plate that holds the motor, pass the zipties through them and wrap the cables. Zip them tight and cut the remaining plastic for a neater finish. 



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
x-motor BCN3D Sigma/Sigmax X motor + Heatsink SKU 14087 
motor-pulley BCN3D Sigma/Sigmax X motor pulley SKU 10446


adjust belt tension eng replace driver eng


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