Drilling into the ceiling to install light fixtures or fans can be a messy ordeal. Debris can end up all over the ladder and floor which adds an extra step to clean up. This simple trick keeps the debris contained and is especially useful when drilling multiple holes.
Deflate an old or unused basketball and cut it in half along the seam with a utility knife. Then drill a 1.25cm hole into the centre of one half of the ball and insert your hole saw mandrel. The ball will catch the debris and prevent it from falling on your face or the floor.
Check out the video in the link below to see the basketball debris catcher in action.
Basketball Debris Shield [Fine Homebuilding]