Following a video I saw on YT about activating a spray bottle with servo motors, I tried to recreate a similar setup. It "kind of" works, but the servos do not perform the full required angle. My guess is, they are simply to weak and thus stop at the point where their force is exhausted. They are super cheap SG90.

Any ideas how to make it work? Should I find another bottle with a less strong spring? Should I get better servos? I'm using a PCA9685 board to create the PWM signals, so I'm a bit worried that I have to stick to the 50 Hz / 1-2ms analog servos, whereas the strong servos are usually digital with other frequency range. Hints welcome!