Aluminum alloy window handle rotation is not smooth, usually caused by the following reasons:

1. The mounting screws are too tight or skewed. If the screw is tightened too tightly during installation, the internal transmission part of the handle will be deformed by force; if the screw is deflected, the rotating shaft will be squeezed. The solution is to loosen the screw and re-install it in place to ensure that the handle base fits the window sash plane and the rotation axis is perpendicular.

2. The transmission rod (lock rod) is bent or misaligned. During the repeated opening and closing of the window sash, the transmission rod may be bent due to the impact of external force, resulting in increased friction with the lock seat. The handle panel can be removed and the drive lever checked for a straight line and replaced if necessary.

3. Internal spring or gear wear. Window handles with high frequency of use may cause fatigue breakage of internal return springs and wear of gears. In this case, it is necessary to replace the internal parts of the handle or replace the handle as a whole.

4. Lack of lubrication. After long-term use, the accumulation of dust in the transmission part and the drying of the grease will also cause the rotation resistance to increase. It is recommended to apply a small amount of silicon-based grease to the rotating parts every six months to maintain smooth operation.