In article ,
Derek Andrews wrote:

Although you don't say how much inaccuracy there is in the alignment
(and even the best machines will have some tolerance) I think you maybe
expecting too much.

LOL, I was telling a friend off in the shop just they other day; "Stop
being an engineer!" I said. Thanks for the reality check; I too need it
some days.

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.

PK