Flat leather belts are especially hazardous because they tend to be unguarded on crowned cone pulleys. If in doubt, add more clamps. If in doubt, chuck more deeply or use a collet. A turning that comes adrift can damage both the lathe and you. A workpiece that shifts can damage both the mill and you.
Stuff gets hot when cut.
Let it cool before picking it up. Metal cutting generally leaves a sharp burr. Break the edges with a file or a de-burring tool before you release the work for general handling. Don't let kids, wives, husbands, girlfriends, or boyfriends close to metalworking operations without training or close supervision. Chips are extremely sharp.