replying to Graz, d2milleraz wrote:
Open the chuck like you were going to put in a large bit. Unscrew the bolt
inside and remove it. Mine turns clockwise to unscrew, opposite of normal.
Turn the chuck until a small hole in the chuck lines up with the notch on the
top of the housing. Insert an appropriately sized allen wrench or something
strong into through the notch and into the receiving hole. Also insert a
chuck key where you usually would. Then twist the chuck off. (The allen
wrench holds the shaft and pressing on the chuck key turns the chuck.) Mine
unscrewed counter-clockwise (normal) and took a light blow with a rubber
mallet to get it started.) A little unnerving until you've done it once.

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