/diy/ - Do It Yourself

Got this all for $45 a couple of days ago, and the commutator on the impact is pitted to hell and back. It looks like someone spilled motor oil in it and then continued using it heavily, because it was full of black paste from the brushes, so much so that the commutator was just one smooth black mass, no distinction between commutator bars. Got it all cleaned up, but it's pitted. Do the bars on a commutator need to be a specific thickness, or would it do more damage getting it in a lathe and getting it smoothed out?