Things You'll Need
Ball peen hammer
Little else is more frustrating than a drill bit breaking off during a build or DIY project. Depending on how the bit broke off, you have a couple of options for extracting it. If the bit broke off so that a small length of the bit is sticking out from the wall, consider yourself lucky. If the bit is broken off below the surface of the wall, extraction is going to be a little bit tricky, but not impossible.
Bit Is Above the Surface of the Wall
Place a set of vise grips at the broken end of the bit.
Tighten the vise grips around the broken end of the bit.
Twist the grips around counterclockwise while pulling away from the wall until the bit is extracted.
If the Bit Is Below the Surface
Place a washer so that hole in the washer is flush with the hole in the wall. Tap the washer with a ball-pen hammer until the broken end of the drill bit is flush with the washer.
Use a wire welder to weld the inner ring of the washer to the drill bit. Weld an appropriately-sized nut to the washer. Follow the instructions with your wire welder and put on a welding mask and gloves before you do any welding. Allow the weld to set.
Tighten a crescent wrench around the nut. Turn the wrench counterclockwise while pulling lightly away from the wall until the bit is extracted.