Other People's Espionage

I was gifted with a box of correspondence between a husband working for westinghouse and his wife in the post WWII era. The letters don't reveal any secrets about the work he was doing but I'll bet it was government contract work building motors for Navy vessels.  The secret he did reveal was the boredom in having to work overnight shifts waiting for an assembly process to finish, or just trying to finish under deadline. How do I know he was bored? Take a look:

You can see through the thin sheet, the form he used for his creation. I can promise you that if this was discovered in his possession, he would have been in a world of ------- trouble.