Loose Motor Pulley

Diagnosing a Loose Motor Pulley: 

1. On the Viki LCD screen, go to "Prepare" > "Home XY."

2. Select "Move Axis" > "Move X" > "10mm" and turn the dial until the print head is in the middle of the bridge rail.

3. Press "Move Axis" > "Move Y" > "10mm" and turn the dial until the print head is in the middle of the bed.

4.  The stepper motors are now energized and will resist the movement you are about to impart. Ensure the Gigabot remains stationary by locking the rolling wheels, or have someone hold it in place.

5. Standing at the front of the machine, hold the bridge rail on either side of the print head, and apply gentle force backward and forward, parallel to the Y-axis of travel. If skipping or movement is present, a Y motor pulley is loose.

6. Hold the print head by the aluminum baseplate, and apply gentle force left and right, parallel to the X-axis of travel. If you feel it skip and move,  If skipping or movement is present, an X motor pulley is loose.


Important Information: Use caution to ensure the pulley does not slip up or down on the motor shaft. It is set to be 0.015"-0.020" away from the aluminum rail.

1. Remove the faulty motor from the aluminum rail according to the instructions in this video. (The steps will remain the same for both the X and Y motors.) 

2. Separate the motor from the plastic mount by removing the four M3 bolts with a 2.5mm Allen key. 

3. Add red Loctite to prevent the set screw from becoming loose again, and tighten both set screws of the pulley (if there are two) with a 2mm Allen key.

4. Reinstall the motor mount and motor. 

Questions or concerns? Reach out to our support team at or open a support ticket








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