Johns811, I agree with Tim. However, another point is are you using finger inserts, thumb insert. Those items alone cause cracking across the bridge and also the superglue that is used weakens the cover of the ball to a degree.
Also the ball drilling can come into question, if the driller is not using sharp drill bits especially on today's equipmet the vibration on the ball sitting in the drill press will cause issues with the cover. Just my two cents.