Hey, about learning "the loud way"... that makes it sound like one big mistake you can't miss. But tool wear often creeps in quietly. Like, a slightly worn gear cutter will make teeth mesh poorly, so the clock runs slow after a month... not right when you build it. Or a dull pivot drill makes holes a tiny bit too large, and the gears never sit right. It's those slow fails that really teach you to watch for wear before things break.