What Is a Paddle Bit? | Fast, Rough Holes in Wood

A paddle bit (also called a spade or flat bit) is a flat, paddle-shaped drill bit designed for drilling large holes quickly in wood, plywood, and thin plastics, where speed matters more than smooth finish.

When you need to run electrical wiring through a stud or pass a pipe through a floor joist, a paddle bit is the fastest tool for the job. The result is a rough but fast hole up to 1-1/2 inches wide, with a self-centering point that prevents wandering.

Below, we cover exactly how these bits work, what sizes they come in, how to use them without splitting boards, and where they fail—so you know whether this is the right bit for your next project.

How a Paddle Bit Actually Cuts

Unlike twist drills that spiral material out, a paddle bit cuts by spinning a flat steel blade. The sharp center point digs in first to keep the bit from walking across the surface. Two cutting spurs on the outer edges outline the hole before the blade removes the center wood. This design dramatically reduces splintering compared to older designs, though the finished hole is still rough compared to a Forstner or hole saw.

Paddle bits are universally compatible with both corded and cordless drill drivers. The standard 1/4-inch hex shank also works in impact drivers, though the high torque can increase kickback risk.

Paddle Bit Sizes and Construction

Imperial sizes run from 1/4 inch to 1-1/2 inches. Metric versions span 6mm to 36mm. Most bits are heat-treated high-carbon steel or tool steel, which balances hardness with the ability to maintain a sharp edge on job sites.

Standard shaft lengths range from 6 inches to 16 inches. The extra-long 16-inch versions let you bore through thick framing without needing an extension. Shanks are almost always hex-shaped for grip, and many bits come uncoated (bright finish), though some brands offer dark coatings for corrosion resistance.

How to Use a Paddle Bit Correctly

Using one correctly is straightforward but different from a twist drill. Follow these steps for clean results and fewer stalls:

1. Use high speed — Set your drill to its highest speed setting (often marked “2”). Slow speeds make the bit grab and stall.
2. Start light — Apply high speed with light downward pressure until the center point bites fully into the wood.
3. Increase pressure — Once the bit is fully contacting the wood, lean into it with steady downward pressure.
4. Prevent tear-out — Clamp a scrap board behind the workpiece, or drill until the center point pokes through, then flip the piece and drill from the opposite side. This gives you a clean hole on both faces.
5. Mark depth — Wrap tape around the bit at your target depth as a visual guide.
6. Brace the drill — The large diameter creates strong kickback when the bit jams. Keep your opposite arm braced behind the drill’s rear handle.

If the bit stalls, pull it out and clear packed wood shavings from the blade before continuing. Trying to power through a packed bit creates the heat that dulls edges and the torque that twists your wrist.

Drilling the Right Way: A Quick Comparison

If you are buying your first set or replacing worn bits, our tested roundup of the best 2 paddle bits covers which models hold an edge longest and resist heat buildup in heavy framing work.

When Not to Use a Paddle Bit

Paddle bits have clear limitations. They are not designed for concrete, tile, glass, or thick metal. They produce rough holes, so do not use them for visible finish joinery. They also cannot drill at an angle — the flat blade will bind and the center point will drift sideways. For holes smaller than 10mm (about 3/8 inch), a standard twist bit will center better and cut faster.

The kickback risk is real: paddle bits have fewer contact points than twist drills, and the wide blade catches easily. Always keep your bracing arm behind the drill to prevent the handle from spinning into your face or wrist.

FAQs

Are paddle bits and spade bits the same thing?

Yes, the terms are identical. “Paddle bit” describes the flat, boat-paddle shape; “spade bit” is the older name. There is no functional difference between them.

Can I use a paddle bit in an impact driver?

Yes, if the shank is 1/4-inch hex. Impact drivers work well with paddle bits, though the higher torque increases the kickback risk, so the bracing rule matters even more.

Why does my paddle bit burn the wood?

Burning usually means you are drilling too slowly or not clearing chips. Increase the drill speed to its highest setting, and back the bit out frequently to clear wood shavings from the blade.