Paul Kierstead wrote:
Unfortunately, in this case, I think I might not be expecting too much;
For example, if I was to drill out something thin walled like a pepper
mill, the drill would exit the side within 3". This is not error
measured with a vernier caliper; it is serious enough to cause trouble
when you need a reasonably parallel centered hole.


I don't know if anyone has suggested this already, but put centers in
both headstock and tailstock. Retract the quill and bring the tailstock
up, lock everthing and check for alignment. Now backoff the tailstock
and extend the quill and check for alignment again. That will tell you
if there is a problem with the tailstock. Measure any errors, and note
if they are vertical or horizontal.

If the tailstock seems ok, the only way I can think of to test the
rotating headstock is this. Rough out a cylinder, maybe 2x6, between
centers. Now put the cylinder in the chuck, true it up and make a nice
face on the end. Mark the center of the end face with the tip of a skew
chisel, and bring up the tailstock center and check for alignment. Do
this with both the quill in and out. Now carefully part off the
cylinder, face it off, mark the center and test for alignment.

--
Derek Andrews, woodturner

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