Don Stephan
It's hard to imagine a discussion about gouge use without the term "flute" but it's only in the last few months, when I was struggling to help another turner, that I stopped to think about the definition. I can't recall ever seeing "flute" defined with text and diagrams, and it's a basic concept used all the time.

Last month I started to think of a flute more specifically as the space removed when a gouge is made. This morning however I realized this removed or negative space is three dimensional and I think "flute" commonly is used to refer to a two dimensional shape, perhaps defined as the inner cross sectional profile of a gouge, whether spindle roughing, spindle, or bowl. I'm guessing that profile is a portion or arc of a circle on the various types of spindle gouge (roughing, spindle, detail, spindle detail), and the commonly mentioned U, V, and parabola for bowl gouges.

But this makes a "flute" a profile fixed in manufacturing of the gouge, so are then "open the flute" and "close the flute" inherently confusing terms because we cannot change the profile?