"Lloyd E. Sponenburgh" wrote:

"Pete C." fired this volley in news:4d36e6a5$0
:

Locking any axis
you aren't moving will increase rigidity by locking out the backlash in
the axis, as well as protecting it from you accidentally bump the
handle
when reaching for something.


And your point? I do not move the knee except to get to a position.
Once in that position, I lock it. Manual or CNC -- lost motion is your
enemy.

And normally, one would not (say) drill with the knee crank, one would
lock knee-Z at the clearance point, and peck with the spindle feed. Knee
feed is for "getting there", even if the holes are deeper than the
spindle extension length.

It's a mill, not a drill press. On a manual knee mill the quill is there
for quick drill type operations, while the knee is intended for use as
the precision Z axis for milling operations (with the quill locked). My
point is that if the knee needs to be locked to make the table level,
your gibs on the knee need to be adjusted, that is not a normal
condition. Since your CNC mill is based on a manual knee mill design,
the same applies there as well.