Rich Grise fired this volley in news:im6728
:

Is the defining attribute to qualify as a "Turner's cube" simply the
fact that it's cubes within cubes with thru-holes?

No, it's that the multiple cubes within cubes be free from one-another,
and that their peripheries (inside and out) be square and not round.
That was why I asked Ig why he had not completed it...


Or is it primarily an exercise in CNC programming, as opposed to doing
it "by hand," as it were?

The ultimate skill is to do it by hand. CAD and CAM make projects like
this overly simple. It only takes an hour or so to design one in a decent
CAM system, even if you don't have any CAD software available.

There once was a time when a turner's cube was a rite of passage for new
machinists learing their trades (not unlike spending a year at a filing
bench!)

LLoyd