I strongly suggest the DVD titled ... "The Wood Lathe in Rodbuilding with Andy Dear".

As far as mandrels, I don't suggest threaded rod. I have yet to see one that is actually anwhere close to true. To work effectively on hard woods, speeds of 3000+ rpms are common. Folks can get away with cheap threaded rod for low speed cork turning, but on harder materials ... it is a definite "no-no".

You wouldn't catch me using a mandrel with any measurable amount of runout OR one that isn't designed from carbon steel (resists flexing). Buy properly designed tools, live a little longer.

Above all BE CAREFUL ... wear safety gear, know your materials AND always pay attention.