In construction or remodelling it is often necessary to drill through stone and stone-like materials such as brick and concrete. While with a normal drill and drill bit it is next to impossible to drill a large hole, using a carbide or diamond-tipped hole coring attachment on a drill makes the task much easier. For large holes it is never a good idea to use a hammer-action drill.
Attach the hole coring bit to the drill as well as the guiding drill bit which sits inside the hole corer---the guide starts the drilling off and prevents the corer from wandering. Hole corers can cut holes up to about 4 1/2 inches in diameter.
Put on your safety goggles and mask. Set the corer in position on the stone where you want the hole. Turn the drill on and begin drilling. You should not apply a lot of pressure on the drill as this can increase the likelihood of the corer jamming. If the corer jams it can cause injury as the drill will twist suddenly away, resulting in wrist/arm injuries. If possible buy or hire a drill with a safety clutch to prevent jamming.
Remove the guiding drill bit once the corer has bitten into the stone. Drill on a medium to low setting to reduce friction heat. Remove the corer from the stone after the corer's length has been drilled. If need be, remove the core of drilled stone with the chisel and mallet.
Reinsert the drill bit into the cleared hole and continue drilling. The hole won't be able to go much deeper than the length of the drill bit, around 3 or 4 inches more maximum. For thicker stones, consider drilling from both sides of the stone; otherwise larger industrial-style drilling equipment will be required for drilling through stone that is very thick, requiring professional operators.
- If you are drilling into a loose stone, make sure you set the stone up in a secure clamp before drilling.
- Smaller holes can be drilled using masonry drill bits and a hammer-action drill.
- Drilling with a corer can be dangerous due to the kickback from jams. Use extreme caution.