In this step, we will finish tensioning the belt. Please read the instructions first, your belt might have proper tension already, then there is no need for additional screw adjustment.
⬢First, slightly release all the screws holding the motor, otherwise, the "tensioner" won't work (the motor must be able to move).
⬢Using ball-end Allen key start tightening the screw on the rear side of the X-end-motor, but after each turn or two check the tension in the belt.
For optimal performance, the belt must have some resistance when pressed with your fingers. Move the extruder to the X-end-idler and try the belt tension in the middle of the X-axis.
⬢When you achieve optimal tension, please tighten the screws again.