Do I have to drill, and then tap a hole in the blank to fit it on the bottle stopper mandrel and then on the bottle stopper kit, or can I just thread it on like my woodworm screw, and then screw the stopper bottom in later (maybe with a drop of CA)?
I've had mixed results. If it's a softer wood, I usually just twist it on, if it's harder wood, then a tap may be needed. Just support the other end with the live center or you will strip the threads in the wood. Whatever you do, DON'T use CA. You may never get the blank off the chuck.