A screw may break during use for several reasons. While sometimes this can be because of a defect in the screw itself, usually a broken screw results from using a screwdriver or drill bit that is the wrong size for the screw. Removing a broken screw without damaging the surrounding material can be difficult. Special tools will make the job easier.
Things You'll Need
Set of drill bits
T-shaped twisting tool
Mark the center of the broken screw with a pencil. Place the tip of the center punch onto the pencil mark. Tap the back of the center punch forcefully with a hammer.
Drill a hole into the center of the broken screw using a 1/16-inch drill bit. Place the tip of the drill bit into the depression made by the center punch. This will help prevent the drill bit form slipping off of the screw and damaging the surrounding material.
Check the screw extractor's instructions, and make note of the recommended diameter of hole.
Increase the diameter of the hole if necessary by re-drilling with the hole with the next largest drill bit. Repeat with larger drill bits until the hole is the recommended diameter.
Insert the screw extractor's tip into the hole and gently tap it in with the hammer.
Turn the screw extractor counterclockwise with the T-shaped twisting tool. Continue turning the screw extractor until the screw is is completely removed.