wrote in message
...
On Tue, 8 Aug 2017 05:45:19 -0000 (UTC), bob prohaska
wrote:

No matter how straight your lathe was when made it will twist some
when set on a surface that is not true. Then, if fastened down, it
will deform more. No matter what surface you are going to attach it
to
the lathe will need to be leveled in order for it to cut straight.
...
Eric

OTOH you may not notice the twist if the lathe sat flat on the
tabletop without rocking before you attached it. I almost never turn a
continuous cylinder from end to end between centers, because I buy
shafting or ground drill rod the right size to fit bearings and only
modify a short distance on the ends. You may be OK just bolting it
down, using it and watching for issues to correct later, instead of
waiting for a precision level.

A bigger problem than slight bed twist is that the cutting force
deflects the unsupported right end of chucked work. If I drill it for
a supporting live center in the tailstock the space for carriage
travel between the spinning chuck and the tailstock base can become
tight. My lathe came from a trade school and bears multiple scars
where inattentive students ran the carriage into the chuck jaws. That
alone is a good reason to buy (or make) a micrometer carriage stop.
http://neme-s.org/SB_Carriage_Stop/m...riage_stop.htm

They don't really need the micrometer dial, a simple threaded rod with
a finger knob would do because you can set it to the tool bit position
on the work.

I was advised to buy at least one chuck small enough that the carriage
can pass under it, unless the jaws are cranked way out. I have several
now and they are the chucks I use most often.
-jsw