>>11128956It's a silicone like material, it's used for making water effects in dioramas. So once you apply it, it leaves a soft and flexible but thick material.
I used a toothpick to apply some on the ball and the socket, let it dry until it becomes transparent like in pic related. Then heat it up a bit and put it together.
>>11128976Haven't actually tried it for that, but maybe it can help by making it tighter?