I have just turned a couple of aluminum cylinders which are parts for a
machine I'm building. They are about 3.5" in diameter and 24" long.

The finished accuracy I achieved is about 0.010". That is, the
diameter at the "wide" end is about 0.010" greater than the diameter on
the "narrow" end.

This is accurate enough to work in my application, but it raised some
questions for me:

Is the level of accuracy I achieved "typical"? I set up the tailstock
as closely as I could, before machining the cylinders, aligning two
dead centers. Should I find a more accurate way of setting up the
tailstock? How would that be done? Would using a pre-made precision
cylinder of known accuracy, then measuring the clearances, be the most
accurate way?

Suggestions?

Thanks.

- Don