The model is fully 3D printed and does not require any hardware.
It is recommended to open the mitered joint for a better appearance.
The pattern has been adjusted and tested multiple times to achieve a better feel.
The spring is independently designed, and the sound effect varies with different printing materials. In my personal test, PETG produced a crisper sound.
It is recommended to apply a little grease to the red-circled area in the image below for a better feel.