What Is a Hole Saw? | Circular Cutting Bits Explained

A hole saw is a ring-shaped drill bit that cuts a circular hole while leaving the center core intact, ideal for larger diameters.

When you need a hole bigger than a standard twist bit can manage, a hole saw is the tool that gets it done. Unlike a traditional drill bit that removes everything in its path, a hole saw cuts only the perimeter of the circle, leaving a clean plug in the center. If you’re planning a project that needs larger-diameter holes, this guide covers how these bits work, what materials they handle, and how to use one safely.

How a Hole Saw Works

A hole saw attaches to a drill through an arbor—a shaft that holds the saw in the chuck. The arbor carries a pilot bit that extends past the saw’s teeth. That pilot bit centers the cut, letting the teeth engage around the outside edge while the center plug remains inside the cup. After the cut, the plug pops out or gets removed through the saw’s side slots.

This design matters because it cuts cleanly without needing to grind away the whole circle. The downside: hole saws work best on relatively thin materials, and the cut depth is limited by the cup’s height. For thick stock, you may need to cut from both sides.

Hole saws come in many diameters, and the cutting edge material determines what they can handle:

• Bi-metal (HSS teeth): versatile for wood, plastic, and softer metals.
• Tungsten-carbide tipped: built for harder materials like metal and masonry.
• Carbide grit: for tile, stone, and ceramic.

What Materials Can a Hole Saw Cut?

Depending on the tooth material, hole saws cut through wood, metal, plastic, drywall, and masonry. The right saw for the job depends on what you’re drilling into.

For wood and drywall, standard bi-metal saws cut quickly and stay sharp for dozens of holes. For metal, material-specific versions matter—HSS and tungsten-carbide hole saws handle steel, aluminum, and stainless without dulling after one use. Ruko’s guidance on HSS and tungsten-carbide saws notes that the right tooth material prevents premature wear and rough cuts.

For masonry and tile, carbide-grit saws replace the toothed edge with an abrasive surface that grinds through brick, block, and ceramic. Always check the saw’s rating before you start—using a wood saw on steel will destroy the teeth fast.

How to Use a Hole Saw Safely

Milwaukee’s official instruction sheet lays out the assembly steps: insert the pilot bit through the back of the hole saw, screw the saw onto the arbor thread without bottoming it out, align the pins with the back holes, and secure the collar. Tighten the nut securely, then put the shank into the drill chuck.

Once assembled, the cutting process comes down to three things:

1. Secure the workpiece. Clamp it down or use a backing board. A spinning workpiece is dangerous and ruins cuts.
2. Keep the drill perpendicular. Tilted cuts bind the saw and overheat the teeth.
3. Clear chips frequently. Back the saw out of the hole often to eject waste. Forcing the saw causes overheating and tooth damage.

When you finish the cut, the official removal steps are: loosen the nut, lower the collar, and unscrew the hole saw from the arbor. The center plug often stays inside the cup—push it out through the side slot.

Choosing the Right Hole Saw Size

Measure the hole diameter you actually need before buying, since saw sizes correspond to finished hole widths. A 2-inch hole saw cuts a 2-inch hole—there’s no rounding up.

Match the saw to both the material and the drill. Most hole saws fit standard 3/8-inch or 1/2-inch chucks, but larger diameters need a drill with enough torque to drive them. A cordless drill with a 1/2-inch chuck handles most holes up to about 2 inches; bigger cuts call for a corded drill or a low-speed setting to prevent binding.

For the most common household materials, RS Components’ hole saw guide notes that wood and plastic are straightforward; metal and masonry demand the material-specific versions mentioned above. If your project involves drilling a cleaner hole through cabinet doors, drywall, or door hardware, a hole saw is the right tool. If you’re shopping for a set to cover typical home projects, our roundup of the top 7 hole saw options compares the best performers for wood, metal, and general use.

Using a hole saw properly comes down to assembly, clamping, and chip clearing. Assemble the arbor and pilot bit firmly, keep the drill level, and back out to clear waste. Match the tooth material to your workpiece, and you’ll cut clean holes without burning the saw or the material.