Well, since I got my first road bike over 3 years ago (a used bianchi trofeo), I've been overhauling my hubs about once a year but my rear hub clearly gave up the ghost as the pictures I've taken show. I can say somewhat confidently that I know how to tighten the locknuts to allow just the tiniest amount of play as I was taught by a mechanic with many decades of experience. But at some point my bearings began digging out the races and I'm embarassed to say I didn't notice it until one day I felt a lot of play in the wheel. So I tightened the locknuts but then I could notice the hub not rolling nice.
As can be seen from the pics, the bearing races are pitted with signs of rust. Perhaps the rusting started during the previous owner's time with the bike.
Q1: What are the bearing race surfaces? The surfaces are black which makes me wonder if its just hardened steel. But I wonder if they somehow polish the surface or something.
Q2: All the races were pitted (see pics) except the cone from the non-drive side. As you can see from the photo , its surface has a more smoother wear "path". Is this the appearance of normal wear? Does the black coating on the races normally get worn away to this polished silver ring where the bearings are contacting the race?
Any comments/info on hub materials, i.e. what kind of steel are they made of, would be appreciated.