I used to work in a Bradley FV factory and we had "bare hulls" of aluminum Bradleys up on wooden stands until the chassis was added.
Anyway, one of the shop floor "grunts" decided to ring a metal hammer against the hull while my boss, one of the engineer "suits" was inside doing an inspection (no ear protection in those days) - well, blood began pouring from both ears and he's had to wear hearing aids in both ears for well-over 20 years now.
didn't mean to be a downer, but the story was related to one of the posts -wp