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Bits usually break for a reason: the wrong bit for the material, too much side pressure, excess heat, or a worn cutting edge. A cordless drill can supply more torque than a small bit can take, especially in a low gear or when the bit binds. The goal is to keep the bit cutting freely and stop before a small snag turns into a snapped shank.
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Match the bit to the job
Use a bit designed for the material. A standard high-speed steel (HSS) twist bit is fine for wood and occasional drilling in thin, soft metal. For frequent metal work or tougher steel, cobalt or other purpose-made metal bits tolerate heat better. For tile and masonry, use the appropriate carbide-tipped tile or masonry bit; a regular twist bit will skate, overheat, or dull quickly.
Check the bit’s maximum working speed and the drill’s gear range. Bigger bits generally need slower speeds, while small bits can run faster if they stay cool. Follow the bit maker’s guidance when available. If the bit is not cutting cleanly, increasing pressure is rarely the answer: check the bit type, sharpness, speed, and material instead.
Choose between common bit types
| Bit type | Best use | Trade-off |
|---|---|---|
| HSS twist bit | Wood and occasional mild-steel drilling | Affordable, but dulls faster in hard metal |
| Cobalt or premium metal bit | Repeated drilling in steel and other tough metals | Costs more; still needs proper speed and cooling |
| Brad-point bit | Clean, accurately placed holes in wood | Not for masonry or metal |
| Carbide masonry bit | Brick, block, and concrete with a compatible drill | Slow and rough in wood; not a substitute for a metal bit |
If you routinely drill metal, a small set of cobalt drill bits can be worth buying. For a one-off hole in thin sheet metal, a sharp, inexpensive HSS bit is usually sufficient.
Set speed and clutch correctly
Use low gear for larger holes, hole saws, and jobs where the bit could grab. High gear suits smaller bits and lighter drilling, provided the bit and material allow it. Keep the drill straight and let the cutting edge do the work. Pressing harder can stall the motor or force the bit to bend, particularly when drilling a deep hole.
The clutch is mainly for driving screws, not drilling. Set it to drill mode when making holes, unless the manufacturer specifies otherwise. For masonry, use hammer mode only with a bit and drill designed for impact drilling. Do not use hammer mode for tile, glass, or ordinary wood and metal bits; the blows can chip the work or damage the bit.
Keep the bit cool and clear
Heat softens cutting edges and can discolor or weaken a bit. In metal, use a suitable cutting fluid where appropriate, drill at a controlled speed, and pause if the bit becomes hot. For a deep hole, periodically ease the bit out to clear chips. Packed chips raise friction and can seize the bit. In wood, chip clearing also helps prevent burning, especially in deep or wide holes.
Do not cool a hot bit by plunging it into water unless the bit maker recommends it. Sudden temperature changes can damage some materials, and water does not fix an overheated or dulled cutting edge. Let the bit cool naturally, then inspect it before continuing.
Prevent binding and side-loading
A bit is designed to cut along its axis, not act as a lever. Keep the drill aligned with the hole, support the workpiece, and clamp loose stock. If a bit starts to bind, release the trigger rather than twisting the drill sideways. Reverse can help withdraw a stuck bit, but use it carefully and keep a firm grip. A sudden stop can wrench the drill around and injure your wrist.
When drilling near an edge, use a pilot hole if the job allows. For large holes in wood, step up through smaller sizes rather than forcing a large bit into the material. This reduces grabbing and gives chips room to escape. If the drill has an auxiliary handle, use it for larger bits or demanding work.
Inspect the chuck and bit
A loose or off-center bit wobbles, cuts unevenly, and sees extra bending stress. Clean the shank and chuck jaws, insert the bit fully where possible, and tighten the chuck securely. For a keyless chuck, tighten it by hand according to the tool’s instructions; do not use pliers to add leverage. Check that the bit runs straight before drilling. Replace bits with bent shanks, chipped tips, or rounded cutting edges.
For repetitive screw driving, the bit type matters too. A driver bit that fits the screw recess snugly is less likely to cam out and break. Use an impact-rated bit with an impact driver, not a standard drill bit or ordinary driver bit. A set of impact-rated driver bits makes sense if you drive screws often; occasional light fastening can be handled with a basic bit set and a regular drill.
When a bit breaks
Stop the drill and remove the battery before handling a broken bit or adjusting the work. Look for the cause: a dull tip, wrong bit type, excessive speed, poor chip clearance, a crooked approach, or a jammed hole. If the bit snapped while drilling metal, check for a hard spot or a punch mark that let it wander. If it snapped during screw driving, check that the bit matches the screw and that the tool’s torque setting is not unnecessarily high.
Wear eye protection, especially when drilling metal or masonry. Small broken fragments can be sharp, and masonry dust is hazardous to breathe. Fixing the cause—not simply replacing the bit—is what prevents the next break.