Genuine PRUSA MK3- Diagnosing Information Jan 12, 2019

Belt Tensions


  • IMPORTANT: Any adjustment to the belt will need a "Self Test" done to update the values of the belt status. Go to Calibration > Self Test and perform the test before you go to the Support > Belt Status menu.
  • X Belt (Goes left to right, as facing the front of your printer)
  • Y Belt (Goes back and forward, as facing your printer)

Recommendations for Belt Tension

  • PRUSA's Recommendation: 240 plus or minus 40
  • My Recommended: 255-270 (Based on comments on various forums)

Helpful Articles / Videos

Y Belt Issues

Diagnosing the issue


  1. Move the bed manually and see if there's any resistance towards the ends, or in the middle
  2. Check the pulley on the motor, make sure the set screw is on the flat of the shaft and is tight.
  3. Make sure nothing is on the belt that could get wound up in the motor as it moves.
  4. Makes sure the teeth of the motor pulley are clean

First Layer / Live Z