"whit3rd" wrote in message
...
On Tuesday, December 12, 2017 at 4:40:45 PM UTC-8, John B. wrote:

To align head and tail centers you simply mount a piece of stock
between centers and turn a length at the head stock end and then at
the tail stock end - using the same cross feed setting of course.
Adjust the tail stock, if necessary and repeat.

Why bother? Can't you just base an indicator on the chuck or
faceplate,
extend to the taper (internal socket) of the tailstock, and rotate
the spindle
by hand, looking at the reading?

It's easy if the tailstock is near the spindle.

Sure, on a new lathe. My SB 10L suffered the abuse of trade school
students from 1965 to 1991 and every alignment test gives a different
result. I have to take and measure several light finish cuts to sneak
up on the proper diameter.
-jsw