Remove the chuck screw (t-20 inside the chuck). Note that it is reverse thread. Then set the drill to setting 2 and drill speed (to best lock the chuck). Then lock a large (1/2") Allen wrench in the chuck. Hold the drill tightly on a flat surface, and whack the Allen wrench counter clockwise. It should break loose and you can then spin it off by hand.
Alan
August 2013
drill out old screw then get old part of screw in a vice and turn it anti clockwise .
graham
April 2011
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