US Patent 7114869 Ball joint system for drywall finishing tools

The present disclosure describes drywall tools that employ rotatable joints, e.g., ball joints, and methods of using such tools. One particular implementation of a drywall tool includes a body having a recess adapted to pivotably receive a rounded connector of a handle. A retainer carried by the body includes first and second rods. Each of the rods is rotatable about an axis and has a non-uniform circumference with respect to that axis such that such that a surface of the rod is spaced farther from a recess axis of the recess when in its open position than when in its closed position.