We are using Sandvik inserts. An expandable collect but no tail stock. I have a 111.048 OD +/- .011 um with a 94 ID at 6.5 length cut one tool rough separate tool to finish. 120.002 OD +/- .011um with same 94 ID at 18 length cut one tool to rough and separate tool to finish. And 54.009 OD +/- .009um with 32 ID at 23 length cut finish tool from 120 OD is the rough and finish here. Print calls for HRC at 36 to 43. Our last batch was at 42 to 45 HRC. This goes through 3 green operations, heat treat, hard mill, then the hard turn is where I have the most trouble.
So your question about method is very valid. The engineer over this is loaded down with other projects like this. I was an excellent brake press set up tech. Now I have a basic certificate in machining which means I am certified to make a lot of scrap. I have a much better understanding of this part than I did just a few months ago. Now I am the only available expert and now the supervisor. I can run about 6 parts on a finish insert then turn or replace. I back out .070 on x and z and walk it back in. In some cases by the time I am back in I get just a few parts in spec (that vary up and down the tolerance) and I am changing again. I will take any advise on method you can offer.