Quote Originally Posted by sinful View Post
Hello,

it is so called backlash effect. The belt over tensioning actually can even make the situation worse. Hold the both X belt sides firmly together that the Extruder carriage wont move, then take the carriage with your other hand and try to move it in both sides, you should notice some play within the holder where belt is attached to the carriage. If this is the case, you need to fasten the X belt to its holder firmly so that there would be absolutely no play within the belt and carriage. You can do it using various ways:
1. Scale the 20mm calibration box from example files in MakerBot Desktop using non Uniform scaling so it passes just between the belt teeth and holder to set the belt in place. Print it and push the printed piece between belt and holder.
2. Drill the hole through the plastic holder and the X belt together using a 2mm drill. ( Use this option if you are experienced with drilling, because you can damage the belt ) Then use screw to tighten holder and the belt together.
3. Similar as 1st option, just take some paper and fold it until it firmly passes between belt and carriage holder.

I hope you could understand my solution and it helps you.
ty for the info...it didn't fix that problem.