come either CNC-ready or CNC-equipped. Converting a Seig or a Proxxon takes a bit of work - it's good if you have access to a mill on which to do it. Most people say that the Chinese mini-mills are somewhat variable in quality, and need some effort to get running accurately as CNC machines. The Proxxon has a nice built-in spindle but it's really small; the working area is about 1 inch by 2 1/2". If you're a jeweler, it might be worth considering, though.