Karl,
I'd start with a bar over desired size and put centers in both ends.
Then machine/ grind it (adjusting the tailstock to get your diameter true
end to end). Once done, you've set your tailstock true AND made your own
alignment bar for use the next time it is needed.

"Karl Townsend" remove .NOT to reply wrote
in message nk.net...
I'm needing a one inch lathe test bar. Finding ground and polished one
inch material is a piece of cake. The bar needs centers on each end. If I
just chuck the bar in a one inch collet and bore, I'll pass on the 0.0005
inch runnout of my collet to the test bar.

How would you do this? Or do I just buy the test bar?

Karl