If the raw stock is new or newer I have found it to be pretty close. So I cut what I can put through the chuck and start turning. You will turn it concentric then and when you cut it off you should be good. For a QC check you could take a V block and put the new hub in it and set that on any table and lower an indicator over it. Slowly turn the hub and watch the needle. Remember that you will be reading TIR or total indicator runout. Divide that in half for your actual runout. Should be very little at all. If you have runout check your lathe setup, if that is good then your tool is pushing the workpiece meaning too deep of a cut. Good luck and take your time. Try different ideas and develop YOUR methods and style. Remember there is no right or wrong way to run a job.