Insert an Allen wrench into the chuck and turn it to tighten the chuck once you've gotten rid of the screw. When the wrench is strongly in position, established the drill's gearbox to the most affordable setting to lower resistance from the gears. Then, touch the Allen wrench with a club to loosen the chuck from the drill. You can unscrew the chuck by hand once it's loose. Screw your new chuck in its place, tighten it with your Allen wrench, after that change the screw in the center.
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