It's a question about using woodworking tools, of course it's on topic.
Maybe the answers expand the use of some rather expensive equipment, or maybe they clue me in that, oops, I better not try that again.
If someone were to propose turning a turnip, I would be quite intrigued and curious about the answers and experiences of our fellow turners. As a matter of fact, no less a lathe master than Rude Osolnik was known to turn stone on a wood lathe, demonstrating and advocating it in seminars and workshops.
If the context of a question were to be working with non-wood products using a tool normally used for wood in a space that the questioner might normally consider a wood shop I would consider it ON topic. This becomes especially meaningful when the safety aspects of doing so lift there ugly little heads when a different technique might be necessary to complete an operation.