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A clean lock bore is mostly a matter of using the right hole saw, supporting the door, and cutting from both sides. A hole saw forced through the full thickness in one pass can tear out the veneer as it exits. Before drilling, check the lock’s instructions: many standard cylindrical locksets need a 2⅛-inch face bore and a 1-inch edge bore, but not every lock uses those sizes.
What we cover
Check the lock and door first
Read the lock template and measure the door thickness and backset—the distance from the door edge to the center of the bore. Common backsets are 2⅜ and 2¾ inches. Use the supplied template to position both bores; don’t assume the old holes are correctly placed if you’re replacing a lock.
Check whether the door is solid wood, hollow-core, or metal-skinned. A standard hole saw can cut many wood doors, but a metal door may require a bi-metal saw and careful handling. Hollow-core doors have a thin face over a mostly empty interior, so clamp and support them gently; excessive pressure can crush the face or break the thin skin around the cut.
Choose a hole saw and drill
Match the saw diameter to the lock instructions. For a typical 2⅛-inch bore, use a hole saw with a pilot bit and a matching arbor. A bi-metal hole saw is a useful general choice for wood and doors with thin metal skins. For wood-only work, a basic carbon-steel saw can be cheaper and perfectly adequate for a one-off installation, though it may dull sooner and is less suitable for metal.
Look for a saw deep enough to cut through the door thickness, or plan to cut from both faces. A deep cup is convenient, but it does not remove the need to finish from the opposite side if the pilot bit or teeth are about to break through. Buy a kit only if its extra sizes or replacement pilot bits are useful to you.
A corded drill or a capable cordless drill can do the job. Use a drill with a side handle if available, especially with a large saw: the saw can catch suddenly and twist the drill. A hammer drill must be set to ordinary drilling mode, with hammer action off. Do not use an impact driver; its hammering action is poorly suited to controlling a large hole saw.
Compare 2⅛-inch bi-metal hole saws and arbors before buying, and check that the arbor fits your drill chuck and the saw’s thread or drive system.
Tools and setup
You’ll need the lock template, tape measure, pencil, drill, hole saw and arbor, the correct edge-bore bit, clamps, and eye protection. A scrap board held flat against the far side helps reduce tear-out, but cutting from both sides is the more reliable method on a finished door. Remove the door from its hinges if practical, then clamp it securely on padded supports. If you drill it while hung, wedge it firmly so it cannot swing.
Set the drill to low gear and use the clutch or speed control to keep the cut steady. A hole saw needs controlled rotation rather than maximum speed. Follow the saw maker’s speed guidance if supplied; if the saw chatters, burns the wood, or grabs, stop and correct the setup instead of leaning harder.
Cut the face bore from both sides
Mark the bore center from the template, then check the measurement from both the face and edge of the door. Tape the template in place if it shifts easily. Keep the drill square to the door face; a tilted bore can leave the lock sitting crooked or interfere with the latch.
Start the pilot bit at the center mark and bring the teeth into the surface gently. Once the saw has formed a shallow groove, maintain light, even pressure. Let the teeth cut; forcing the drill increases heat, binds the saw, and can split the door. Withdraw the saw occasionally to clear chips, particularly in a thick or dense door.
Stop when the pilot bit is close to emerging on the other side. Remove the saw, move to the opposite face, and align the pilot bit with the small pilot hole. Finish the cut from that side. This makes the two cuts meet near the middle and greatly reduces splintering on the exit face. Keep hands clear of the saw teeth, and unplug a corded drill or remove the battery before clearing a jam.
Drill the edge bore
After the face bore, use the lock’s specified bit—often a 1-inch spade bit or auger bit—to drill from the door edge into the face bore. Mark the latch center from the template and keep the bit level and square to the edge. Drill steadily; pushing hard with a spade bit can make it wander, while an auger can pull itself forward aggressively.
Stop when the bit reaches the face bore. Clear the chips and test-fit the latch. If the latch plate needs a shallow mortise, score its outline with a sharp knife and pare carefully with a chisel. Don’t enlarge the bore to compensate for a misaligned edge hole; recheck the template and measurements instead.
Hole saw options at a glance
| Type | Best for | Trade-off |
|---|---|---|
| Carbon-steel hole saw | Occasional cuts in wood | Lower cost, but wears faster and is not the right choice for metal skins |
| Bi-metal hole saw | Mixed wood and thin metal-faced doors | More versatile; still needs the correct speed and careful chip clearing |
| Carbide-grit hole saw | Some abrasive or composite materials | Specialized; usually unnecessary for a standard wood door lock bore |
For a single interior wood door, the least expensive correctly sized saw is often enough. If the door has a metal skin or you expect to make more cuts, a bi-metal saw is a better buy. A drill with a side handle can also make a large saw easier to control, but it is not a substitute for clamping the door.
Common problems and fixes
Splintered veneer: The saw likely broke through from one side. Stop before the pilot exits and finish from the other face; a backing board can help, but it must sit flat and be clamped.
Burning or slow cutting: Teeth may be dull, packed with chips, or turning too fast under heavy pressure. Clear the cup, ease up, and replace a worn saw. Smoke is a warning to stop, not a sign to push harder.
Wandering bore: The pilot may have slipped, or the door may have moved. Re-clamp and verify the center before continuing. If the bore is already badly misplaced, check whether the lock’s trim will cover it before attempting a repair.
Saw binds in the cut: Release the trigger and hold the drill securely. Do not twist the saw free while the drill is running. Once stopped, disconnect power, remove packed chips, and check that the door and drill are still square before restarting.