"MrCheerful" wrote in
:

No, chucks are standard RH thread or they would unscrew when
putting screws in or when the drill jams.

MrCheerful


You're right. The first part is still valid:

....hit with a mallet or rubber hammer *in the correct direction*.

My mis-recollection was of some idiot (not me!) belting hell out
of a chuck key with a steel hammer, trying to unscrew the chuck
the wrong direction.