Measuring brake hubs.

Todays mechanics are mostly just parts replacers. In the old days it was standard procedure to always turn new drums "just in case". When you turn a drum you can choose to cut "little" or "much". Taking a "little" to true it up may be under .010. For the best job, I recommend turning. Just chucking up the drum before turning, you can see if it's out-of-round.