In article ,
JonBoy wrote:
...hit with a mallet or rubber hammer *in the correct direction* as
the chuck is (probably) on a LH thread.

No - a standard chuck has a right hand thread since basic drills go
clockwise. Reversing drills have a locking screw which is left hand thread.

--
*The most wasted day of all is one in which we have not laughed.*

Dave Plowman London SW 12
RIP Acorn